Wikipedia:Reference desk/Archives/Science/2007 July 27

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July 27

random number generation by the human mind

How does the mind do it? And have there any been any experiments to see just how non random they are? When I rattle off a few they tend to end in a multiple of 3 and they're all decimal numbers from 10-99.. --froth^t 01:51, 27 July 2007 (UTC)

Not exactly a study, but I do know that what humans think of as random often doesn't match with something that's actually random - for example, I recall reading about a professor (of statistics, I assume) who got his class to write down a "random" string of fifty coin tosses either by making it up or by actually flipping the coins, and he could tell which was which by the fact that the real ones often had long strings of either heads or tails (say 5 or 6 in a row), whereas the made-up ones didn't, because we don't think a string of HHHHH in the midst of fifty trials appears "random". Confusing Manifestation 02:23, 27 July 2007 (UTC)

Statisticians often misunderstand what people mean by saying a string like HHHHH doesn't look "random". What they mean (though they don't always know this formally) is not, "this is not possible given that each trial is independent" (which is how statisticians interpret them), but rather "a series of homogenous results is less likely than a series of varied results given that each trial is independent". In that sense the brain of the "common person" is completely correct to see HHHHHH as being less likely to be caused by a random generator than HTHTTHH or something like that. The odds of getting homogenous results from independent trials are far less likely than getting mixed results. (There is an article on this exact question using your exact example: Lola L. Lopes, "Doing the impossible: A note on induction and the experience of randomness," Journal of Experimental Psychology: Learning, Memory and Cognition vol. 8, no. 6 (1982): 626-636.) --24.147.86.187 20:42, 27 July 2007 (UTC)

I concur with Confusing Manifestation.

I suspect that humans are less likely to pick "special" numbers, so the digits 0, 1, 5 and 9 might be underrepresented. Your own experience tends to show this: you tend not to pick 0 as the first digit of a two digit number.

There is a parler trick where one is asked to pick a number from 1 to 50, with the conditions that both digits are odd and they are not the same. Then they are told "your number is 37." It works surprisingly frequently. But I think I understand why: only 8 numbers pass both conditions: 13, 15, 17, 19, 31, 35, 37 and 39. The only one that does not contain a "special" digit is 37.

I do not have a reference to the psychology, but David Blaine performed the trick live on his TV show Street Magic. Baccyak4H (Yak!) 03:04, 27 July 2007 (UTC)

You might be interested in W.A. Wagenaar,"Generation of random sequences by human subjects: a critical survey of the literature" (PDF)., Psychological Bulletin 1972, Vol. 77, No. 1, 65-72. Rockpocket 07:12, 27 July 2007 (UTC)

If you know that you aren't going to manage to produce a series of random heads and tails, is there any easy "mechanism" one could apply mentally to make your results random? One thought that occurred to me is to use odd/even distance between vowels in some text to determine change/repeat. Thus "And dId thOsE fEEt In AncIEnt tImEs" generates 44221223142 which might be HHHHTTTHTTT. ? -- SGBailey 13:35, 27 July 2007 (UTC)

When I am asked for just one digit, I wait a few seconds, then look at the second hand of my watch, modulo whatever appropriate number to get the right range. While this is hard to generalize to more than one digit (in a short length of time), it does avoid any artifacts caused by nonuniformity and nonindependence of letter distributions in the English language. You win some, you lose some...Baccyak4H (Yak!) 13:45, 27 July 2007 (UTC)

Well, if you're allowed to use some text, why not RAND's compelling 1955 magnum opus "A Million Random Digits with 100,000 Normal Deviates"? --TotoBaggins 14:26, 27 July 2007 (UTC)

So long as you start selecting from at least the second decimal place, this would be a good idea. Nothing like a little light bedtime reading. Baccyak4H (Yak!) 15:44, 27 July 2007 (UTC)

There's a joke waiting to be made about another Rand and intentionally senseless books. —Tamfang 03:45, 30 July 2007 (UTC)

I think there are some pseudo-random number generators that computer programmers use that are simple enough that you could do them in your head - and which have reasonably random outputs. You might need to remember (say) a four hex digit 'seed' number from one use of your mental randomizer to another - but that's not too hard. Something like the Gold code can be implemented using a Linear feedback shift register which you could easily simulate (in your head) like this:

One time: Memorize any 4 hex-digit number (representing a 16 bit binary number), it can't be zero but any other number will do. This is called the 'seed' number.

1. Whenever someone asks you to mentally toss a coin, recall the number you remembered - say "Heads" if it's odd or "Tails" if it's even.
2. When you have a free moment or two (but before you have to mentally toss another coin), do this:
   1. Since the number you are remembering is in hex, it's easy to find the bits at positions 0,2,3 and 5. If there is an odd number of '1' bits, add 0x8000 to your number - otherwise, don't.
   2. Divide the result by two - discarding the remainder. (I hope your mental arithmetic works in hex!)
   3. Forget your old number and remember the new one ready for the next time you have to mentally toss a coin.

I think the tricky part is remembering the new number each time...it would be really easy to forget the new one and remember the older one by mistake. However, imagining a set of 16 weird objects - one for each of the hex digits 0..15 and placing them next to each other in some ridiculous setting - might work. (eg There is a Cow pushing a complete set of printed volumes of Wikipedia against which is leaning "the platinum spork of terrible answers" and a bright green insectoid alien is running from them - so my number is 4F36 because that's 4 legs, the biggest thing you could possibly imagine(F is the biggest digit in hex), 3 tines and 6 more legs). Clever selection of the images to remember will make the extraction of the bits earlier go more quickly.

The resulting sequence of 1's and 0's is pretty random - it has the same number of ones as zeroes and it doesn't repeat until done it 65,535 times. Most computer programs use random numbers generated like this (although usually with a longer seed numbers and different sets of ).

Let us know how that works out! SteveBaker 16:16, 27 July 2007 (UTC)

The human mind does not generate good random numbers. When you have people think up "random" numbers they generally come up with the same numbers over and over again or gravity towards some numbers as seeming "more random" than others. There have definitely been experiments; if you look under keywords for "randomness" and things like that in psychological journal indices you can find lots of articles on these sorts of topics. They have been pursued by researchers since the 19th century at least, as they have implications to how well observers record data (see, for example, personal equation). --24.147.86.187 20:42, 27 July 2007 (UTC)

I recall hearing that when asked for a random number between 1 and 100, the most common choice is 37 and the least common is 20. I don't remember what research might have justfied this conclusion though. Dragons flight 20:47, 27 July 2007 (UTC)

Using the ground for a ground

Surely there are more ideal electical grounds than just running a pipe into the dirt.. do laboratories and things use big water pools or hunks of metal or something to take care of dangerous electrical potentials? --froth^t 02:19, 27 July 2007 (UTC)

As far as I know, and unless the ground is dry, a nice hunk of metal (doesn't have to be a pipe, but doesn't have to be anything too elaborate) gives you as good a ground as you're going to get. (And stop calling me Shirley.) —Steve Summit (talk) 02:31, 27 July 2007 (UTC)

For modern buildings, see Ufer Ground.

In an electrical generating station or substation, grounding is not achieved with a pool of water, or "hunk of metal." Instead, ground rods around the property at a number of locationsare driven to a sufficient depth (probably 20 feet or more) to achieve a stated low ground resistance, such as under 10 ohms each (or whatever the engineer specifies). A longer ground rod means lower resistance. Then these are connected by heavy cables. This may be bonded to the building steel and the rebar in the concrete and the incoming water main. Another trick, such as for a facility in rocky areas, is to install grounding electrodes in permanently moist soil such as a spring, or to install electrodes in a well, or to bury a wire mesh grid. A substation yard may have a grid of metal conductors buried below the gravel to achieve equipotential during fault conditions. A radio transmission tower at a broadcasting station is likely to have radial ground cables buried in trenches extending radially from it in all directions. Any of these can and does corrode over time, so after many decades it may be advisable to test the integrity of the system and the resistance of each driven electrode. Edison 17:10, 27 July 2007 (UTC)

So why do they use dirt? Just that it has a lot of water in it so it's really conductive? It seems like you'd be at the mercy of environmental conditions and have a wildly fluctuating capacity.. something I doubt is very good for electronics --froth^t 00:51, 28 July 2007 (UTC)

What do you mean, "So why do they use dirt?" They don't use dirt, they use the ground -- although as it happens, most often, the ground is made of dirt.

Sorry if this sounds sarcastic, or like a tautology, but that's the way it is. No, dirt is not a particularly good conductor, and wet dirt isn't all that much better. But it is (by definition) at ground potential, and it seems to dissipate charge well enough for most of our purposes. —Steve Summit (talk) 01:01, 28 July 2007 (UTC)

Here's a cute story about a grounding problem. Probably an urban legend, though. And for sure, there is no such place as "Winnepeg, Ontario" (or Winnipeg, Ontario, either). --Anonymous, July 28, 2007, 03:21 (UTC).

Industrial equimpment grounding (i.e. not antennas or transmission lines) is only to provide a reference for people. meaning that the building steel and structures and people are electrically connected to the ground. By tying the ground to one of the electrodes of the source (i.e. a tap to a transformer), electrical faults can be detected and circuit breakers tripped. No one wants to eneergize different parts of their house to two different voltages and find out by touching it. Therefore, everything that isn't power is grounded to the earth so that there is never a potential difference between people and appliances. The connection to the earth really only has to be as good as the persons connection to the earth. It would be bad if the person had a better connection to the earth than the electrical equipment. I don't know how different it can be but I suspect it can be dangerous. --Tbeatty 06:23, 28 July 2007 (UTC)

We are talking about a ground here, which means we are talking about a way to conduct electricity into the ground. "Running a pipe into the dirt" is the same as providing a path for electricity to flow into the ground. (ground = dirt) A metal pipe will provide a path resistance for electricity to flow into the ground. This method works. There is no need to sophisticate or complicate something that works as good as we need it to. Larger buildings may need more pathways or more effective pathways or both because of the amount of electricity needed to power them, but it all simplifies down to providing a path for the electricity to exit the circuit. With out the ground, AC electrical devices wouldn't work.Mrdeath5493 17:28, 29 July 2007 (UTC)

Actually, that last bit isn't true, in general. Except in unusual circumstances, the net amount of current flowing between a conventional AC circuit to or from the ground is negligible. The primary reason why grounding is important in electrical systems is for safety; secondary reasons are to reduce electrical interference, and perhaps to reduce various kinds of galvanic action and corrosion.

Most electrical circuits work perfectly well without a ground, and this is actually a bit of a problem, because if there's something wrong with your grounding, you might not notice it until a short circuit or other fault electrocutes you or starts a fire, when it should have (i.e. if a proper ground were in place) merely blown a fuse. —Steve Summit (talk) 02:55, 30 July 2007 (UTC)

Individual Timeline

My understanding of general relativity is that an object moving at near the speed of light in relation to a stationary object, would return to find that his native environment has far exceded his own. My question is what defines "near" the speed of light? Assuming my understanding is correct; wouldn't a fixed individual observing another individual simply walking away, or some other commonly exercised speed, differentiate the individual timelines of the two people? So therefore, isn't every individual living in their own personal space/time?
75.134.4.229 04:04, 27 July 2007 (UTC)Alan

This question is coming up on a near-daily basis and I would like to correct one misconception right away. While the "two twins" example refers to one twin traveling at high speed, general relativity refers to high energy and low energy objects. Traveling at high speed is merely one concept of a high energy object. So, "near the speed of light" means that the object contains more energy than mass. "At the speed of light" means that the object is all energy (no mass). Absolute zero (a complete state of rest) means that the object contains all mass (no energy).

As for time-lines, they do not exist. Time is merely a dimension. I can walk down the street. You can run. It doesn't mean we have our own individual streets. We just walked down the same street at different speeds. The concept of time-lines (aka world-lines) is used in science-fiction to do magic and make impossible things possible. -- Kainaw^(what?) 04:12, 27 July 2007 (UTC)

I don't know about your background, but worldlines were used in my graduate general relativity course to describe the motion of relativistic particles. Dragons flight 04:29, 27 July 2007 (UTC)

Note - you are not using the science-fiction version of world-lines. You do not use a concept that every particle exists in an infinite array of worlds and infinite number of times. While the names are the same, the concepts have nothing in common. I read the question as asking if each person on earth has their own little pocket of time that they carry around with them. I have my little version of time. You have yours. You can't see mine. I can't see yours. There is nothing in common between the two. That is why I thought of the science-fiction version of time and space. -- Kainaw^(what?) 05:11, 27 July 2007 (UTC)

Most relativistic corrections are proportional to something like $\beta -1$, where $\beta ={1 \over {\sqrt {1-{v^{2} \over c^{2}}}}}$, so relativistic effects become important when $\beta$ becomes larger than 1 to whatever degree of precision one cares about measuring. And yes, everyone has a slightly different experience of time, but the difference is miniscule for everyday speeds. Dragons flight 04:29, 27 July 2007 (UTC)

World lines only do impossible things if you decide to ignore the laws of physics. And to say a complete state of rest equates no energy, it would be more proper to say "no kinetic energy" (provided you're ignoring thermal and other fluctuations, but these would mainly apply to individual particles). "No energy" is also a meaningless concept. Everything has energy, always. There are many kinds of energy besides that of motion, and even vacuum has energy. Also, saying no mass at the speed of light, you must specify that you mean "no rest mass" (ie, if you were to slow the object down below the speed of light, it would have no mass, related to why it can't slow down). Someguy1221 05:00, 27 July 2007 (UTC)

As I stated above, I was referring to the science-fiction use of timelines, which are often called world-lines. I was not referring to the scientific term "worldline". As for "no energy" - it is, in my opinion, easiest to explain to a person who is grappling with the basic concepts of the theory of relativity that anything traveling at the speed of light is all energy and anything at absolute zero is no energy. If they take an interest in the topic, they can later work on determining the mass of a photon or the energy of an absolute-zero particle. Basically, I do not find it helpful to throw equations and complicated details at a newcomer to scare them away from the topic. -- Kainaw^(what?) 05:22, 27 July 2007 (UTC)

In general relativity (and in special relativity, though it's less often taught), the elapsed time between two events is the length of the worldline between them. Since different worldlines have different lengths, the elapsed time for differently moving objects can be different. There's nothing mysterious or mystical about this. It's only as strange as the fact that if two people take different routes between Chicago and New York, they'll end up with different mileages on their odometers. If it seems stranger than that, keep studying physics until it doesn't. -- BenRG 14:37, 27 July 2007 (UTC)

When people just walk around, their timelines do diverge and reconverge just like in the Twins paradox - but the difference between classical Newtonian stuff and reality at those speeds is so tiny that there is no way to even measure it. That's because at the heart of the math is this (1-v²/c²) term. 'c' is an ungodly huge number - and 'v' is tiny - so the answer is very, very close to 1.0 and you can't tell that anything weird is happening (although it is!). Even at a quarter of the speed of light (which is insanely fast), the differences between 'normality' and what's really happening would fairly hard to spot without doing some careful measurements - it's only when you get up at the 90% or so range when v starts to look a lot like c and that formula is starting to get noticably smaller than 1.0 that you start to see weird things happening. So there isn't some special speed at which relativity 'turns on' - it's always there - it's just that the effects are too small to see until you get very close to 'c'.

Theory Of relativity

Friends, Can any one explain the Theory Of Relativity in the most simplest way, B'cos any article I Read looks too complicated ??? Thank u.

You might be interested in this. Someguy1221 05:12, 27 July 2007 (UTC)

or this --Philc 14:18, 27 July 2007 (UTC)

Special Relativity (SR) all comes from the deceptively simple observation by Einstein that Galilean relativity—which is what lets you perceive, in your frame of reference, that you are sitting perfectly still even though the planet you are sitting on is rotating at 1670 km/hr—applies to all physical phenomena except the speed of light. Most of SR is extrapolating the implications from that—it ends up having all sorts of meanings in respect to the relationship between space and time.

But SR only works when you are thinking about frames of reference that are moving at a constant speed and in a constant direction—that is, frames of reference that are not accelerating (ergo the "special" aspect of it — it is not generalizable to accelerating frames). In formulating General Relativity (GR), Einstein addressed this issue, which, in turns out, hinged on a redefinition of what gravity is (instead of a "force", as Newton had it, it turns out to be that what we perceive as gravity is a warping of space and time in the presence of mass). The reason it hinges on this requires a bit more understanding of SR than you probably have, but if you worked your way through some SR it would make sense (basically a gravitational field behaves like an accelerating frame of reference, hence the relationship to the SR issue).

Taken together, SR and GR are considered the Theory of Relativity. Now that explanation barely touches the surface — it is but a brief conceptual/historical skimming — but I have found that thinking about it in those terms helps to make all of the rest of it make a little more sense: a lot of it is just extrapolation from a few somewhat simple axioms, which is how Einstein liked to do things. --24.147.86.187 20:15, 27 July 2007 (UTC)

OK - I'm awarding the platinum plated spork to [[24.147.86.187]] for this explanation. The OP doesn't understand any of the explanations out there - and you start handing out frames of reference and such. Argh. We need "simple" here!

Here we go with "simple"...(The pedants will probably tear this to shreds - but it's "good enough" for common understanding of this mind-bending concept):

If you stand still and throw a ball at 10mph, you see it heading away from you at 10mph. If a friend runs after the ball at (let's say) 3mph - then from his point of view, the ball moves at 7mph relative to him. If he runs at 9mph, the ball drifts slowly ahead of him at just one mph - and if he actually manages to run at 10mph, the ball seems to fly along right next to him at zero speed. This much is what we know and see every day - and we've known this stuff since the time of Newton and even Aristotle.

But here's the problem: An experiment by Michelson-Morley to measure the speed of light came up with some weird results - the upshot of which is that light is weird and special. If you flash a flashlight to send out a pulse of light (at the speed of light from your point of view) - and your friend goes chasing after it (REALLY fast...in a really, really fast spaceship) then the odd thing is that he sees your light beam flying away from him at EXACTLY the same speed you do. This is nothing like what happened with the ball! With the ball, the faster he ran, the closer he got to catching it. With light, no matter how fast you run, the light beam still shoots away from you at the speed of light!!! This is very strange. When you look at the lightbeam, you can see it moving at the speed of light. When you look at your friend, you can see him almost keeping up with it...but when HE looks at the light beam, he realises that he's not even close to catching it?!? Two people - two totally different ideas about what's happening! Which one of you is right? Well, both of you.

Einstein worried about that - how could it be that if your friend chased after the light pulse at 99% of the speed of light, you'd see him not quite catching up with it - but staying pretty close...but he would see the light shoot away from him at the speed of light - no matter how fast he runs?!?! It turns out that this rather strange situation comes about when you and your friend are moving at dramatically different speeds (like getting close to the speed of light). What happens is that your perception of time and distance gets warped...not just your perception of it...distance and time really does scrunch up when you move fast. If both you and your friend are holding nice large clocks - you'd see that his clock is ticking MUCH faster than yours is. He would see that your clock has slowed way down. That's why there is a difference in what you're seeing. From his point of view, you are imagining he's not losing much on the light beam because your brain is running slowly. From your point of view, you think he thinks he's not catching the light beam because his brain/clock is running so quickly!

The "why" of this...is really not known. "It just is" - that's how the universe operates.

At this point we could get into the math and frames of reference and other technical stuff - but the bottom line is that our perception of a nice, simple universe where clocks keep good time and things stay the same size no matter how fast they move - is ever so slightly wrong. But at speeds we can actually attain, this 'wrongness' is so subtle that we really can't measure it. However, when things start moving an appreciable fraction of the speed of light, time, space, mass...all of that changes depending on how fast you are moving compared to whatever it is you are measuring.

The "Relativity" part comes about from the observation that in space, you can't tell whether you are moving - and the stuff you are moving past is staying still - or whether you are stationary and everything else is moving the other way. "Everything is relative" I guess.

That's a much simpler explanation - it doesn't cover anything like all of the terratory. SteveBaker 04:12, 1 August 2007 (UTC)

Sea water

Why is Sea Water Salty, While rivers and Ground Water are perfect and have no Saline Charecterestics ??

Rivers are fed by rain and melting snow - which is mostly water. As it flows out to the ocean, it will pick up sediment, minerals, salts, and all. But, it will remain mostly water. The oceans are full of salt (have been for a very long time). It comes from the animals/plants living in it and the salts coming in from the rivers. Mostly, the salt just stays there. You can look at trapped salt lakes which were once parts of the ocean. Many years have gone by and the salt is still just sitting in the lake. -- Kainaw^(what?) 05:26, 27 July 2007 (UTC)

Agreed. Rivers with a tiny amount of salt flow into oceans, where the water then evaporates and leaves the salt. Over time, the salt content thus builds up in oceans and "dead seas", until it reaches the point where it precipitates out as salt beds and formations. Note that oceans and terminal lakes are also higher in many other dissolved minerals, for the same reason. StuRat 06:57, 27 July 2007 (UTC)

Is there any way to stop my budgerigar 'pleasuring himself'?

This sounds like a silly question and it's embarassing but I swear that I'm not making this up. I have an 14 month old male budgerigar who has recently started to masturbate using various objects in his cage. He'll hook his rear end under his perch, swing or ladder and hump away until he gets himself off. He's doing it several times a day now.

Is there any way to stop him or put him off from doing this?

Buy a female budgerigar and a bigger cage. ugen64 06:34, 27 July 2007 (UTC)

Looking after baby budgies is a big, big responsibility. I'm not ready to breed him yet. --81.76.8.159 07:01, 27 July 2007 (UTC)

On the bright side, the behaviour is probably seasonal; it's "high season" now in the Northern Hemisphere, but it will pass.

Atlant 12:30, 27 July 2007 (UTC)

Buy a webcam and make a little seed money. --TotoBaggins 14:29, 27 July 2007 (UTC)

Are you sure he doesn't maybe have an infection or an itch or something that's bothering him? I'd ask a vet. SteveBaker 15:29, 27 July 2007 (UTC)

Google for 'bird masturbating' comes up with a bunch of links Nil Einne 16:10, 28 July 2007 (UTC)

FTL

I don't understand why FTL travel implies time travel. Okay, it's fairly obvious that physically moving through space at a faster velocity than light is a scientifically meaningless notion. And clearly, any journey you make into your own past light cone results in a causality violation (which is what I understand as time travel). But what if I just instantly blip from here to Mars - specifically, a version of Mars which is currently "elsewhere", neither in my past nor future light cone? I can see why this would result in apparent time travel from the point of view of, say, an observer on Mars, who would see me arrive there before she the light of my departure from Earth reached her. But I don't see that apparent time travel is a contradiction and I don't see how a causality violation would arise. -- SamSim 09:26, 27 July 2007 (UTC)

But in some other reference frames, you will appear to have arrived before you left, according to special relativity. --Spoon! 13:30, 27 July 2007 (UTC)

Which is not a logical contradiction, just a possibly surprising result, like the twin paradox. You can add FTL travel to special relativity without contradiction. What you can't do is have a notion of FTL cause and effect (sending and receiving) which doesn't break Lorentz invariance. It should be easy to see why: you can always construct a trip of two consecutive FTL jumps which take you into the past light cone of your starting point. Nobody really understands the thermodynamic arrow of time, so it's not entirely clear what's really going on here. -- BenRG 14:24, 27 July 2007 (UTC)

I took a look at the article, but I don't understand what Lorentz invariance is, why it would be a bad thing to break, or how this instantaneous Earth-Mars blip (or two of them) would break it... SamSim 16:53, 28 July 2007 (UTC)

I can't think of specifially anything cataclysmic that would happen but I wouldn't want to be in the same universe as you when you tried it.. think about it, from the martians' refrence frame you're both on earth (they could look through a telescope and see you) and standing right next to them. I don't know if the big brain physicists have decided that something weird would happen but common sense tells you that if you teleport back it'll be impossible to interact with yourself since despite what the martians think, you weren't still on earth when you teleported back. But things are going to look mighty weird from the martians point of view- first some guy visits them for a couple moments but they still see him on earth, then he disappears and a few minutes later he disappears from their telescopes for a few moments and reappears. o_O --froth^t 15:38, 27 July 2007 (UTC)

Essentially the same thing as what froth said happens when you go faster than sound (only with listening) or even faster than brownian motion (when smelling). What you experience from your point of reference is what you see after accounting for that effect. — Daniel 23:06, 27 July 2007 (UTC)

Well yeah, sound and smell are one thing, but the speed of light is supposed to be the fastest that information can travel.. does the universe isplode if you can teleport instantly? --froth^t 00:54, 28 July 2007 (UTC)

primitive Weighing scale ?

What is the most primitive or rudimentary type of scale that a pre-metal or stone age society could invent? Something portable and easy to make from raw materials found in nature, but not metals. Maybe not so accurate, but better than nothing. For weighing herbs or drugs, not for entire humans. Maybe something using sand or a liquid?--Sonjaaa 11:07, 27 July 2007 (UTC)

The traditional scales is a wooden rod with a weight suspended at one end and held up by a string in the middle. At the other end is suspended the material that you want to weigh. The supporting string can be moved around against various marks to get a read out of different weights. This could have been made in the stone age, but probably wasn't. It seems that there is no picture of it in the weighing scales article! GB 11:29, 27 July 2007 (UTC)

Commons (http://commons.wikimedia.org/wiki/Weighing_scale) has a bunch of pictures (although the one I was really hoping for, with a witch on one end and a duck on the other, wasn't there).

Atlant 12:34, 27 July 2007 (UTC)

Hahah, I get it! Capuchin 12:38, 27 July 2007 (UTC)

Looks like we've got a joker on our hands.. you'd better watch out atlant :[ --froth^t 15:43, 27 July 2007 (UTC)

A joke at nobody's expense at the end of a helpful answer, that doesn't lead to confusion and misunderstanding, is absolutely not a problem. Skittle 22:22, 28 July 2007 (UTC)

I doubt there was a need for weighing things in the stone age. It's only when you have money or at least a very well established (and formalised) barter system that you really need to weigh things. If I have a chunk of meat that I don't need and you have a pile of nice ripe berries that you'd like to swap - we look, we haggle, we do the deal. It's only if I have a butcher shop and I'm selling meat at three groats per lump that you start to ask yourself whether I'm selling lumps that are smaller than the guy down the street who is also charging three groats per lump. A set of scales quickly allows you to set a price per pound that can easily be compared and standardized. In any case, scales and balances only COMPARE weights - without a set of standardized known weights, they aren't much use. SteveBaker 15:26, 27 July 2007 (UTC)

If a hunter or gatherer obtains food and eats it, he does not need to measure it. His stomach and the greater or lesser feeling of satiety or hunger is a wonderful measure of his success. But when agriculture is developed, and there is some standard of providing a part of the crop to the Temple or the Keepers of the Great Stone Idol, or to the Chief, or to the common granary, then measurement is needed. A gourd can serve as a "standard scoop" until it breaks. A Standard Holy Gourd of Taxation was perhaps the first unit of measure for volume. In the US flour is measured still by volume in recipes, while in many other countries it is routinely specified in grams. The greater precision of weight probably came along much later, but no metal at all is needed to make a beam type balance. Get 2 pans, show that the scale is balanced, put a standard weight on one pan (a little stone idol would serve admirably), add grain to the other until the beam is level, and there you are. Edison 16:56, 27 July 2007 (UTC)

Actually, your method for making a beam-balance is not correct. Just because the beam balances doesn't make it 'right'. If one arm of the beam is longer than the other - but the weight of the empty pans is unequal to the same degree (as is likely if you determine where to place the fulcrum experimentally) - then when you put weights in one pan and something to weigh in the other, you'll get the wrong answer. You can show this by piling up grain in pan A until it balances the little stone idol in pan B - then moving the grain into pan B and the idol into pan A. If it STILL balances then it's a fair balance - but the odds are good that it won't! SteveBaker 13:50, 29 July 2007 (UTC)

The simplest I know of is lifting and seeing how hard it is to hold up. The only materials it requires are a person with at least one hand and whatever you're weighing. — Daniel 23:00, 27 July 2007 (UTC)

The relevant article is Steelyard balance. --Heron 19:20, 29 July 2007 (UTC)

PINE TREE

HOW MUCH WATER DOES A PINE TREE TAKE UP FROM THE GROUND? Jamec IT LOOKS LIKE WHEREVER PINE TREE IS PLANTED, THE SOILS BECOME TOO DRY, E.G IN AUSTRALIA THE PLACE IS GETTING DRIER, IN S.AFRICA THEY STARTED UPROOTING IT AFTER KNOWING ITS BAD EFFECTS, ARE THE COUNTRIES PLANTING IT SAFE IN THE NEAR FUTURE OR THEY ARE ABOUT TO FACE CLIMATE CHANGE?

It depends on the type of pine, size and environment of the tree. -- SGBailey 13:23, 27 July 2007 (UTC)

Being evergreens, they by nature move less water than a deciduous tree. Gzuckier 14:36, 27 July 2007 (UTC)

From the pine article: "...they are fast-growing softwoods that can be planted in relatively dense stands, and ... their acidic decaying needles may inhibit the growth of other competing plants in the cropping areas". Contrary to Gzuckier, I'd think that fast growing trees would tend to consume a lot of water, especially in dense plantations. The other point is their inhibition of the growth of other plants; by doing this they can also lead to a very dried out soil, especially in hot conditions, as the soil will be more exposed to the air. However, as SGBailey said, it will depend on other factors like type, size, etc. Having said this though, it seems a long bow to blame their planting for climate change in countries that have planted them. --jjron 15:23, 27 July 2007 (UTC)

heh, sounds like Rainbow Mars... a giant tree absorbs all the water from mars and rockets with it to earth, where it dries up the entire planet --froth^t 15:45, 27 July 2007 (UTC)

According to [1](abstract only) a 100 year old lodgepine was observed that transpired 40-44L/day. That is only one specimen though. As noted above, it depends. 161.222.160.8 22:53, 27 July 2007 (UTC)

Solid bloodveins

Hey

I was wondering, why does some people, especially men have very visible and "strong" bloodveins that is visible through the skin over the biceps, and down over the underarms and at the backside of their hands?

I see that especially those who train and exercise alot tends to have this, while many other people again do NOT have visible bloodveins at all... I was thinking maybe it is because those people with "strong" and visible bloodveins have more oxygen in their blood - and it has always been said that it is a sign of good health a strong body. Something which to me sounds correct as I have learned that the more oxygen our blood are capable of taking in the better, for those with much oxygen in their blood often have good stamina and constitution and are stronger in sports/physical activities. And then it makes sense i guess that these things will improve by exercising, running or training in various ways that will improve our fitness and form. But we also see this often at older people that they have much visible bloodveins as well, so I don't know...

So, what is the reason for those strong visible bloodveins that some of us have? Is it indeed because we have more oxygen in our blood than some other people? I know that both things are normal, I'm just curious what is the reason, what makes it so? and does strong solid and visible bloodveins mean anything, like that we have good bloodcirculation or something?

Thank you, Krikkert

Krikkert7 14:08, 27 July 2007 (UTC)

Having very prominent blood vessels is due to having a low amount of body fat. --TotoBaggins 14:32, 27 July 2007 (UTC)

As Toto said, it is mainly due to low body fat (which, as you suggest, can be closely related to doing a lot of exercise). Additionally, as is commonly the case, genetic factors also have a significant influence, i.e., you could inherit the propensity to have prominent veins (as I have), so the vessels may be more or less prominent in different people with the same body fat. --jjron 15:29, 27 July 2007 (UTC)

Creationism

Is the only reason in the US that creationism is given any respect (i.e. more than other equally paradoxical, fallicious beliefs such as the tooth fairy) is the amount of people that would be up in arms if it was - rightly - dismissed as rubbish. How can people stand by and say its ok to complete refute centuries of hard fought scientific understanding in exchange for something written by one man with no basis and handed down by word of mouth. Philc 15:00, 27 July 2007 (UTC)

To make a career out of politics, a politician has only one goal - to get re-elected. Everything else is judged based on how well it helps re-election prospects. Apparently, many politicians feel that they need to show some support for creationism to be re-elected. As for why the public believes in creationism - most people do not know much about science. All they know (without valid reason) is that a bunch of evil white-robed men are continually trying to attack their belief in God and they have to grab at anything that makes them feel better. -- Kainaw^(what?) 15:17, 27 July 2007 (UTC)

Antidisestablishmentarianism. I think the problem is that the constitution effectively prevents religious teaching in government-run schools. The hard-core religious types want to get religion taught in schools by any means possible - and one possibility is to come up with a fake "science" such as intelligent design that imply religion yet are (perhaps) sufficiently legal to allow them to be taught. There are similar efforts in other fields - teaching the Bible as literature for example - and getting educational vouchers as a back-door way to get the government to pay for religious schools. All of these may be seen as attempts to subvert the ban on the government sponsorship of religion. SteveBaker 15:19, 27 July 2007 (UTC)

If the tooth-fairy was discussed in the Bible then that would also attract far more attention and support from the religiously minded, although it would not be as significant as the creationism issue. Since creationism/evolution deals with our origins - where we come from, who we are - it cuts deep into our psyches. It seems that some people (or in the case of the US lots of people) are unable to mentally deal with the reality that we originated via purely natural processes, as opposed to being a preferred creation of an all powerful superbeing. Why it is more prominent in the US than in other developed countries is a different issue that is also quite interesting. --jjron 15:42, 27 July 2007 (UTC)

It is more than "being able to mentally deal" with it. In the US the history of creationism is deeply tied into the history of religion in this country and the history of fundamentalism as a social and political movement in the 1960s. Why the US is different is a historical question, not a cognitive one. (If you are interested as to why that is, Ron Numbers' The Creationists is a great book on the subject, and very recently came out in a new edition which goes all the way through the Dover case!) --24.147.86.187 20:04, 27 July 2007 (UTC)

I think the questioner and some of the answers are confusing matters of faith with matters of science. Certainly the pope's latest comments shed light on the difference. Religion and science are not at odds. --Tbeatty 19:30, 27 July 2007 (UTC)

They are easily at odds if you don't accept your assertion that there is a difference between "matters of faith" and "matters of science." Such an assertion of there being a difference is itself a metaphysical position, one which many people (both religious and non-religious) reject. (Both the Pope and Richard Dawkins would agree that both religion and science make statements about the naturalistic world which cannot be reconciled, whereas a "compromiser" like Stephen Jay Gould would assert that they are different realms of description, for example.) --24.147.86.187 19:58, 27 July 2007 (UTC)

The question is more about society than either science or religion, although I find that the stereotypes of "religious" people are not getting any kinder with time... ◄Zahakiel► 19:39, 27 July 2007 (UTC)

Agreed, they are at odds to the degree that religion purports to offer an hypothesis about the natural world, or any other areas of knowelge, including the soft sciences. The religious method of inquiry is irrational (hence its based on faith, which is blind in nature), and thus fundamentally at odds with the scientific method that is based on facts and observations.Giovanni33 21:50, 27 July 2007 (UTC)

The problem is that science can't even answer the question "What is knowledge?" A tree, a rock, a star are all physical things. "knowledge" is less tangible. It is a metaphysical question that cannot be answered by science because it is a postulate of science that it exists. --Tbeatty 22:25, 27 July 2007 (UTC)

I think you're the one getting confused here. What the question answer seems to getting at is the way many Americans reject evolution outright and espouse creationism as a scientific alternative to evolution. Many scientists don't really give a damn about what people want to believe as part of their religion. However creationism is clearly not a science and treating it as such, or denying evolution as a scientific fact is ridiculous. But sadly, this appears to be fairly common in the US. Yes, there is a difference between matters of faith and matters of science. That's exactly the problem, many Americans including the current President don't seem to get that... Nil Einne 16:06, 28 July 2007 (UTC)

"Given any respect" — by who? It is not given any respect by scientists. If you are talking about "by politicians" then the answer is somewhat parasitic on whether it is given respect "by the non-expert public", and the reason it is "given any respect" by them is because it is bound up in questions about the role of religion in the United States, etc. --24.147.86.187 19:55, 27 July 2007 (UTC)

Just want to set a bit of perspective here: religion has been the force in human society for all of recorded history. Empiricism has only been around for about 400 years (though it was favored by aristotle) and has only become the popular belief in the last few decades. The belief in science is not the de facto choice, and many of you will look quite foolish a few centuries or possibly decades (if something significant happens) from now when mankind has moved onto some other popular philosophy and they make fun of the old scientists who rejected the metaphysical. In more mystical language: just because this generation lacks the faith to believe in the unobservable doesn't inherently invalidate such studies. The universe is indifferent to mankind's whims and any spirit realms there might be out there aren't going to poof out of existence just because man declares it off-limits to their science. Not everyone follows the same thought patterns- some can accept the idea of believing in the unobservable, while some find it ridiculous because they must be able to prove everything they believe. But that's not the only way of doing things.. --froth^t 01:07, 28 July 2007 (UTC)

You seem to be getting confused here. Most scientists don't say the 'spirit realm' is off-limits to science. In fact, it is the believers that say so. Instead, scientists say that if the 'spirit realm' really exists then why can't we observe it? And believers say, well it can't be observed in any way shape or form but you should still believe it's there because I say so... Nil Einne 16:02, 28 July 2007 (UTC)

OK fine. My point is that there's no telling who's right- the only thing in support of the view that things must be observable to have meaning is science.. and the scientist is basing his whole method of reasoning on science. The only thing in support of the view that things can have meaning without being observable is faith.. and the believer is basing his whole method of reasoning on faith. Scientists are so smug in thinking that their way of thinking must be the best (if they even recognize that it's only Yet Another way of thinking) since it's the most recent, but recentness is only valued within their own realm of science! The truth is, they're new at this game and that's not necessarily a good thing, though they'd say new is best --froth^t 23:47, 28 July 2007 (UTC)

You just can't put religion and science on the same level as philosophies like that. It's not just 'yet another faith'. Where science clearly deviates from other philosophical standpoints is that it proceeds step by step in a methodical way from known things - advancing by mathematical proof and careful experiment. Science makes predictions that can be tested. These things mean that the chances of science being proved wrong in any major way is as close to zero as anything we know. The idea that in a few decades, centuries or millenia, we'll have found something as an alternative to science is just laughable. I suspect we may increasingly demand more rigor (as mathematicians are tending to do) - I would imagine other changes in methodology - but at it's core, a philosophy of life that is grounded solidly on reality with demonstrable step-by-step proofs is here to stay - and that's all that science purports to be. All religion is unfalsifiable - science rejects anything that's unfalsifiable and that's a black-and-white distinction. You can't deduce anything from religion - it's a dead end based on wishful thinking. SteveBaker 13:42, 29 July 2007 (UTC)

I'm not impressed by science's ability to prove itself- the obsessive need to correctly describe the external world is just another philosophy, and one that's not necessarily permanent or even valid. It seems to be evolutionarily beneficial at this point in humanity's existence so it's burned into our brain paths or whatever.. but there's no reason that can't change on a fundamental level. You've referenced a possible revolutionary scientific discovery that could change scientific theories (but not methodology) as we know it.. but you're ignoring a higher-level possibility: a significant change in the way people think. Like I said, it's happened before. This interest in science and -to a more basic degree- rationalism is rather recent and hasn't existed for quite a bit of recorded history (let alone all of human history), let alone enjoyed popular belief. While science may very well be correctly describing the universe, I have my doubts that any humans will care throughout large tracts of our future (in fact I wouldnt be surprised if a recurring focus on science turns out to be a rather minor part of human history once it's all said and done, though I guess the same could be said by others of others- like religion).. and I have my doubts that correctly describing the universe has any kind of cosmic significance whatsoever. Like I said, just a little bit of perspective on the great and mighty Empire Science. --froth^t 02:14, 30 July 2007 (UTC)

I don't understand anti-science feelings. What I can understand is being opposed to the arrogance of those who say things like "science is #1, and religion is bunk". But again, there's not a good reason to doubt "science's ability to prove itself". The way it proves itself, such as relying on materialistic explanations, is the only way science should work. Coming up with metaphysical explanations may be good in explaining the unexplainable, but it doesn't help in advancing scientific knowledge.128.163.224.198 18:56, 1 August 2007 (UTC)

It's true that in casual conversation and when speaking less-than-carefully, people can seem to put just as much faith in science and the scientific method as religious types do in their various bibles and belief systems. However, even more importantly than the step-by-step nature SteveBaker described, a key concept of true science is that it carefully, deliberately, and explicitly denies faith. No one is required to take any scientific result on faith; everyone is free (nay, encouraged) to suspect it, to doubt it, to question it, to attempt to reproduce it, to attempt to falsify it, to suggest alternative hypothesis. Moreover, everyone who publishes a result is obligated to provide, on a silver platter, all the prerequisites and methods by which the new result was derived, making it maximally easy for anyone else to reproduce (and, perhaps, to falsify) the result.

Also, science understands, and attempts to make allowances for, human foibles and (mis)behavior. Scientists are people, and they're prone to the same kinds of rivalries and jealousies as anyone else. However, responsible scientists and scientific journals erect guidelines and rules which are supposed to ensure that scientific truth is determined by actual science, not by tenure or tradition or inertia or prestige or politics.

Since scientists are people, they do make mistakes, and one can point at various reasonably egregious examples of how science has occasionally, in practice, fallen short of its ideals. (One well-known example, discussed by Feynman, is mentioned on our Millikan oil-drop experiment page.) However, over time, the process does discover and correct its mistakes, and scientific truth inches asymptotically ever closer to reality. —Steve Summit (talk) 15:57, 29 July 2007 (UTC) [edited 20:29, 29 July 2007 (UTC)]

I did the Millikan experiment when I was in high school - it was almost impossible to get it to work - we had errors over 100% - at which point (because the experiment relies on calculating integer multiples of some common number), we could get no conclusive results whatever. It's frankly astounding that Millikan came so close to the correct answer. But it's certainly telling how people were prepared to err on the low side to try not to throw off Millikans' result by too much. Feynman was my hero...quite possibly the smartest person ever to have become a scientist. SteveBaker 01:01, 31 July 2007 (UTC)

Bear in mind the influence of religion in American cultur, society & politics appears to be far greater then most other developed Western countries. Nil Einne 15:55, 28 July 2007 (UTC)

WHY do people constantly think its either all or nothing?? What if man evolved on a different planet eons ago, and then either came here or was brought here. After these travelers original machinery, devices, and technology education began to fail, they hit upon easy to understand similies to explain what happened. "War in heaven, fall from grace, garden of eden, etc". ) If you think about it we really have no fossils of any transition man do we?? There should be billions of artififacts but they only come up with an only occasional "piltdown man" (already proven to be a fake to hype media attention to the fakers). WHERE are all the fossils? We find the dinosaurs and every other creature but no "Transition Man" ? WHY? Maybe its because T-Man evolved on another planet far far away ! This makes both creationism (space travelers came here and reproduced, they were eventually thought of as GOD because they knew how to manipulate even the genes and atoms of nature), and truly these ancestors of man did evolved but just not on earth.. End of arguments.. both are correct with a little modification. TripleBatteryLife 19:07, 29 July 2007 (UTC)

Er, actually there are dozens of intermediate fossils between what we consider humans and what we consider non-human primates. We even have an article about it called: List of hominina fossils. Why not check it out rather than spouting a bunch of nonsense about evolving on another planet? Matt Deres 21:11, 29 July 2007 (UTC)

Yeah - I agree, this is a commonly used argument put out by the creationist/intelligent-design nut-jobs - but it's not true. We have a pretty clear step-by-step set of fossils. Sure, there is the occasional gap - but we aren't talking about: Fossil #1: A marmoset, Fossil #2: A modern human. We're talking about: Fossil #1: A skull very similar to a modern human - with almost identical brain size, 2mm longer canine teeth, 10% larger brow-ridges, and 15 degrees more forhead slope, Fossil #2: A modern human. Do we have a protohuman fossil with 5% larger brow ridges? Probably. How about 2% and 7%? Maybe not - that's a gap - but it's a tiny one. But fossils are actually very rare - the conditions required to form them are exceedingly special. We can't dig up every square inch of the earth's surface to a depth of a few hundred feet to look for them. It would be surprising (and perhaps even a little suspicious) if there were no gaps whatever. We find dinosaurs - yes - but there are gaps in their history too. As time goes on, we find more skulls and the gaps get smaller. Once in a while, we find something weird (the "Hobbits" for example) that causes a branch and maybe a gap. But like I said - there are bound to be the odd stubborn gap. But please - don't take my word for it - take a trip to a decent natural history museum (pick one in a big city who have a decent stock) and look at the evidence yourself. Somewhere there will be a showcase full of skulls - lined up in a row from something more primitive than a chimpanzee to a modern human - the difference between any two adjacent ones is noticable - but not enough that you'd seriously doubt that one could have come from the other - that's not a horribly flawed gap-ridden historical record as the intelligent design people would like you to believe. It's a pretty convincing demonstration of what we believe is true. Ask really nicely at a large museum (preferably call in advance) and some staffer may even offer to take you behind the scenes to rows of boxes on shelves where you can see a bunch more skulls.

You are correct in saying that it's POSSIBLE for both theories to be true - that some creatures evolved whilst others were popped into existance by magic. But it's not NECESSARY. This business of not believing things that it's not necessary to believe in - always going for the most simple, most mundane explanation - is very important. Scientists call it "Occams Razor" - and whilst it's not always true - it's always proven to be a damned good first guess. Newton didn't think to worry about his laws of motion maybe being wrong at insanely high speeds - he didn't need to, he used Occams Razor to make the assumption that his low-speed experiments would hold over all speeds. In that case, he was wrong. Only when later experiments showed some surprising results were people driven to look for the more complicated answer that Einstein came up with. But that's a very rare thing...almost always, the simplest answer is the right one.

It's like you look into your sock drawer tomorrow morning and find 10 identical pairs of black socks in there (just like on the previous night and the night before that). It's POSSIBLE that some devious/weird pervert/cat-burglar broke into your house during the night, stole 5 socks and replaced them with 5 almost identical ones - then snuck away without leaving a trace! You can't prove that didn't happen...you really can't - but you don't go around believing it for no particular reason. People who suspect burglars are swapping out socks in the middle of the night wind up in the padded cells wearing a jacket with unfashonably long sleeves! Why would you think that? You'd also have to admit the possibility that space aliens also swapped out a few socks using a sock-o-matic raygun - and that some of them were teleported away to another astral plane by deamons but were returned by kindly angels who spotted the problem. There are quite literally an infinite number of unnecessarily complicated theories you can come up with for every single thing that ever happens to you. But you naturally seek the simplest possibility...that your socks stayed in the drawer the entire night.

A belief in God (or gods - or that intelligent design coexisted with evolution) is every bit as unnecessary as these wild theories you seem to be having about socks recently! If you're prepared to believe that your socks stay put - then why not believe the super-simple, self-evident, easily demonstrated theory of evolution? Gods are not necessary for the functioning of our universe - over the last century or so, we've gained enough knowledge to explain things down to the smallest and largest things humans can detect - we have great explanations for everything beyond maybe the first couple of nanoseconds of the life of our universe - we know how and when (more or less) the earth will end - and we're down to just a couple of options for getting a good idea of how the universe will end. It's pretty clear that we have fairly mundane explanations that make everything tick along just fine with very simple laws of nature.

SteveBaker 00:44, 31 July 2007 (UTC)

Its neat that you still have no link between what most would call ape and what most would call intelligent human! If so put up instead of spouting a plethora of "specie" none of which are what I would call "TRANSITION MAN" ! And if this transition man exists in quantity, where are the millions of fossils from him? waiting. —Preceding unsigned comment added by 209.16.117.50 (talk • contribs) 20:06, 31 July 2007

1. We have plenty of links between apes and humans. But they're not creatures halfway between apes and humans; they're not steps on a hypothetical chain by which humans descended from apes. Because humans didn't descend from apes -- we each descended from a common ancestor.
2. We don't have millions of fossils of anything. As Steve Baker pointed out, fossils are exceedingly rare. It's rather remarkable -- and a testament to the persistence of paleontologists -- that we have as complete a picture of the prehistory of modern life as we do.

—Steve Summit (talk) 23:15, 31 July 2007 (UTC)

OK Mr/Ms 209.16.117.50 - I'm not going to "shut up" - this stuff is fact and it's right to explain facts to those who don't understand them. So instead, I'll be more than happy to "put up".

First, let's clearly lay out the ground rules: Firstly - and very importantly, neither I, nor the expert evolutionists claim that we evolved from the chimps, or the apes, or any other animal that's still alive. The claim is quite clear: Humans and chimps both evolved from a common ancestor - a creature that has long gone extinct because both the proto-chimps and the proto-humans out-performed it.

So I guess that by "Transition Man" you mean a fossil of a pre-human who is midway between modern man and the last common ancestor of both chimpanzees and modern men? If that's not what you mean - then tell us clearly what you DO mean by that term. Meanwhile, I'm going to assume that this is what you seek.

Well, sure! No problem whatever!

"TRANSITION MAN"
(Australopithecus africanus)

It's been calculated that the last creature that was the ancestor of both chimps and humans lived somewhere around 4 or 5 million years ago. Fossils of Orrorin tugenensis and Ardipithecus from that sort of era clearly have features common to both modern human and modern chimp and to no other modern creature. One of them is the ancestor of all humans and all chimps - and fossils from FIVE of these animals (found in Kenya) are carefully preserved in a handful of museums where you could (in principle) go and see them. But these represent the fork in the tree. They are still pretty different from either chimps or humans. So what happened in the transition between then and now? Well, please turn your attention to: List of hominina fossils - it has references and photos for fossils at intervals of about 100,000 years everywhere between the time of Orrorin (maybe 4 million years ago) to the present day. So - which of the dozens of fossil species between then and now would you like to pick as your "Transition Man"? Let's pick one chronologically halfway between us and Orrorin - that would be maybe 2.5 million years ago. There you go: "TRANSITION MAN" (in your terms)...is 2.5 million years too old? OK then we have Homo ergaster fossils from 1.5 million years ago, or Homo_erectus from 700,000 years ago. Maybe 2.5 million years is too close to modern humans to meet your criteria? Well, how about Kenyanthropus platyops from 3.5 million years ago or an almost complete skeleton of Australopithecus afarensis from 3.8 million years ago. I mean, really!

What exactly do you need that we don't have?!?

Now, you wonder why there aren't "millions" of these fossils. That's simply because fossils are really rare - even fossils of common creatures are rare. Realise that the earth didn't have 6 billion proto-humans living on it. We were rare animals back then - it's only with our spread throughout the world and our discovery of fire, tools, agriculture, cities that we got above a million people. Even as recently as the time of the Egyptian pyramid builders, there were less than ten million people. There are probably only 150,000 chimps alive right now - there may have been that few proto-humans alive a million or two years ago. For some of these intermediate species, it's quite possible that less than a million of them ever lived. But even if there were millions of them - how many would end up fossilised? For a fossil to form, you need a really lucky set of conditions:

• the creature has to die someplace it won't be ripped apart by scavengers.
• it has to be buried completely in rather special chemical conditions so it won't decompose too quickly.
• that burial has to happen fast enough to ensure it doesn't decompose before minerals can leach into it and form a rocky cast.
• then, it's no use if that happens where the earth is being subducted underground or sinking into the ocean or eroded away by wind/rain/water.
• it has to end up where we might find it. We need it to form someplace close to a modern rock quarry - or a cliff or where we excavate a mine or deep building foundations or something. If it's buried even 5 feet into the cliff face, we'd never find it.
• even then, it has to form someplace where paleontologists are actually looking.

All of this (along with the relatively few numbers of these creatures in the first place) means that we don't expect to find more than a few of each - it's just really, really unlikely.

Someone earlier asked how come we have so many Dinosaur fossils and so few proto-humans. Well, we have lots of Dinosaur fossils because the dinosaurs were around for 160 million years - we've only been here for 4 to 5 million. There were thousands of species of dinosaurs - and they were the dominant life forms in all sorts of habitats, so there were a heck of a lot of them - so we have lots of fossils. Early humans probably only lived in small areas of Africa and southern Europe. But we have quite a few fossils - statistically about what you'd expect - and ENOUGH TO TELL THE STORY. Note, for example, that we have a LOT more proto-human fossils than we have proto-chimpanzee fossils - so we've been fairly lucky in that regard.

Did I 'put up' adequately? I'd be very happy to expand on any part that you didn't understand - if the fossil you have in mind for "TRANSITION MAN" isn't what I described - please get back to me and tell me exactly what you are missing and I'm pretty sure I can find it for you. The thing is, this evolution stuff happens to be the truth - so there is plenty of evidence for it. SteveBaker 03:34, 1 August 2007 (UTC)

TripleBatteryLife 21:00, 1 August 2007 (UTC)

RESPONSE : 1st. Your transition man looks too perfectly human to be a true transition. 2nd. For a transition to occur from perfect ape to perfect human you would have to have a transition time of perhaps millions of years. Where is the fossil evidence of the perhaps millions of variations that would have to be there? You fail in that also. You would have us believe on "faith" that ape LEAPED to pefect man in one birth? Strange for a scientist to believe in statistical impossibilities. So you who say you do not believe in faith base your whole "belief" system on faith in LEAPING THE GAP! Is it a religion you belief? If so what is the name ? : The LEAP FROGGERS RELIGION of Stubborn Refusal to accept the data? In truth there would have to be massive fossil remains of perhaps 100,000 or more at least, different variants, of the necessary progressive mutations from ape to man for any scientist worth his/her salt to believe it. Sciences best friend is the data. Your data shows the first men pehaps but not all the massive variants that are mandatory in evolution. SO THERE IS A GAP you can't explain except by your own religion of LEAP FROGGING! Do you see how silly the lack of data makes it sound? 3rd. You say you believe in the speed of light and the theories of relativity. This makes you believe that time dan dilate (spec theory). This in turn makes you accept that time could go backwards (as some religions speak it did once for 14 minutes). If that is so then how do you know for sure that someone or something did not go back in time and might be at your elbow even now? (0r do you believe anything supernatural must be an undigested bit of potato as scrooge said?). Also if you believe in relativity then you must accept that that would make interplanetary travel very much easier. still waiting for the massive residual fossil evidence of the missing GAP that would require at least 100,000 different mutations including the one thread that led to man. Se Le Vie! TripleBatteryLife 21:19, 1 August 2007 (UTC)

Replying to you point by point:

1st: OK - so you want something that looks less human - so go back a million years or so - the further you go back in time from now back towards that common ancestor of chimp and man - the less human they look. If you would PLEASE just take a moment to read List of hominina fossils - you'll see (for example) Australopithecus afarensis from 3.8 million years ago - it looks nothing like a modern human - yet it has features that no chimpanzee has - and that all humans have. But then you'll probably say that it looks too 'apelike' - OK so come back through the list of our ancestors on that very same List of hominina fossils page and you can pick something that looks as human - or as apelike or anything in between...truly - don't take my word for it - GO AND LOOK!

2nd: You demand evidence of the millions of inbetween variations - but as I explained, that's impossible because fossils simply don't form that easily - and we don't find them that easily. But the gaps are SMALL - it's not like we don't have a really good range of body forms ranging from one extreme to the other - we do. I'm absolutely not demanding you leap from "perfect ape" to "modern man" on one leap. I'm asking that you take 100,000 year baby-steps because we have fossils (as you will clearly see if you bother to actually look at List of hominina fossils instead of pretending that it doesn't exist. We have documented evidence for about 40 different steps between the last ancestor of chimp and man - and the present day. That's pretty good. Each step looks a lot like the one immediately before it - the variations between (say) the 2.7 million year old fossil and the 2.8 million year old fossil are comparable to the differences we see today between someone with one set of facial features and another. Those two fossils are so amazingly similar, it takes a trained paleontologist to tell the difference - I very much doubt you and I could. Heck - you think that the 2.8 million year one already looks like modern man - so no huge, unleapable gap over the last 2.8 million years.

You also say that we scientists are floundering around struggling hard to explain these gaps...I really don't see where you get that idea from. These gaps are very easy indeed to explain - I already did so in fact. FOSSILS ARE VERY RARE. There - that's the explanation. We don't have a fossil for every generation over the past 4 million years because that would be something like 200,000 fossils - and the total number of human fossils that have been found from all of history is probably a few hundred at most.

Please just stop and think about this for a moment. If you were right - and fossils are actually common enough that we could find them through all of history and there were indeed massive inexplicable gaps - then we'd have (say) 1000 Kenyanthropus platyops fossils from 3.5 million years ago - then an inexplicable gap - then maybe a couple of thousand Australopithecus afarensis fossils from 3.8 million years ago...but we don't! We have maybe a couple of each. Those fossils that we DO have are roughly equally spaced out over time - that's not indicative of big, mysterious gaps that we need magic to fill - it's indicative of fossils being very rare. We know they are rare from independent work - did you know that we didn't find the first chimpanzee fossil until just two years ago? Yeah - fossils are rare - so you can't have a million of them to fill in the gaps. So - there's your explanation - we have some 100,000 year-ish gaps because we only found a few hundred proto-human fossils and statistically it's not at all surprising that they are spread out the way they are. Far from this being a horrible flaw in the theory of evolution, it actually backs it up. If we had a million human fossils and only a few tens of thousands of dinosaurs - then we'd be wondering what was wrong with the theory.

But here - let me ask you a question. If you believe that some magical being stepped in and made mankind all in one go - when did that happen? Between which pair of my steps? Because if you pick a time period thats fairly close to the present (say: 70,000 years ago) - then we have much larger numbers of fossils between 100,000 years ago and today and the 'gaps' such as they are are very small indeed. If you choose a period older than that (suppose mankind popped into being 2 million years ago according to your theory) - then you are saying that some creature evolved from 4 million years ago until 2 million years ago - then *poof* some magic happens - then mankind evolves for another 2 million years to get us where we are today. Which of the 100,000 year-wide gaps are you going to choose? Pick carefully because maybe tomorrow someone will find a fossil slap bang between your two limits and now you're in trouble because you only have a very tiny gap between the creature who existed just before the *poof* event - and the one afterwards. There may come a time when that gap gets so small that you wonder why God bothered? I mean - the creature he 'designed' is so amazingly similar to the one that was already evolving away happily towards the same destination?! But don't let me put words into your mouth. Tell me - when did the *poof* event happen?

3rd. Yes, we're pretty sure about relativity too. I believe that time can dilate for an observer in a different frame of reference IF our frames of reference are moving at some significant fraction of the speed of light. This does not in ANY WAY make me accept that time could go backwards...nope - sorry - go read what that nice Mr Einstein actually said and not what the religious nuts are telling you he said! Unlike religion, science documents every step of the way, clearly, and publishes it for everyone to read. Take the time - go read it. Modern physics makes it pretty evident that backwards time travel is impossible.

You ask whether I believe anything supernatural must be an undigested bit of potato - well, I wouldn't have said that. I would have said that everything we typically label as 'supernatural' is complete and utter bullshit...all of it. That's why we invented the word...it means "everything that we can't demonstrate in a carefully controlled experiment...or something like that.

You state (very, very incorrectly) that if I believe in relativity then I must accept that that would make interplanetary travel very much easier. Nope - quite the contrary - it makes it ridiculously difficult. The faster you approach the speed of light - the more power you need to get there - and as you start to get up into relativistic speed - you need exponentially more fuel/energy to do that. No - I most certainly don't believe that interplanetary travel is easy...it's ridiculously difficult.

You say you are still "waiting for the massive residual fossil evidence of the missing GAP that would require at least 100,000 different mutations including the one thread that led to man". I'm interested to know why you feel the need to see so many. Over 4 million years with a generational span of (let's say) 20 years - you are demanding to see one fossil for every two generations. Surely you know that evolution doesn't happen that fast! Compare the skull of an ancient Egyptian mummy from 8000BC to a modern human and you won't find any differences large enough to measure. Over 10,000 years we don't need more than a couple of fossils to show small steps of change. We have them about every 100,000 years - well, yeah - we could wish for more.

But you really are missing the point. You are looking to find a way to wedge your intelligent designer into a huge span of evidence leading from mankind back to the first bony fish...even further perhaps. Scientists are saying "Here we have a really simple explanation for how life arose on Earth - we can see evolution happening all around us - everything from lactose tolerance in modern man to how bacteria in hospitals manages to evolve to avoid being killed by our antibiotics. Every single piece of evidence that we've ever found fits beautifully into that simple theory. The only two things we have to know are that:

1. The DNA/RNA molecule changes over time due to random mutation and sexual reproduction. Since the 'design' of an animal or plant comes from those molecules, animals and plant MUST change over time.
2. If one animal has a random DNA change that makes it better able to survive - it will survive when it's relatives do not.

If those two things are true - then evolution is inevitable - you can't even concieve of a way to stop it from working to change entire species over time. If species were NOT changing over time - we'd be at an utter loss to explain why not!

So why do we need to invent (without ANY evidence) some kind of magical intervention in the case of modern man? The exact same mechanism that gave T-Rex his enormous jaws and big counter-balancing tail explains how come the TB disease is getting harder and harder to cure - it explains why it is that all other mammals lose their ability to digest milk soon after being weaned - but most humans do not. It explains all of everything that we see around us in the natural world. It's a truly beautiful explanation - it's so simple that even I can understand it - and it explains everything. What's not to love?! ...unless of course you're worried that it puts your supernatural all-powerful being out of business? SteveBaker 23:20, 1 August 2007 (UTC)

You still haven't provided the massive residual evidence that your theory requires to be authentic. There must be millions of years of transition variants from perfect ape to perfect man, where are these massive amounts of residual fossils? DNA variants would many many many but you have none in quanties needed to validate your theory. I daresay if you were born in the 1700's you would teach that manned flight was impossible and would never happen because after all your studies didn't teach you that. Can you seriously say that you never had anything spiritual or supernatural happen to you ever ever ever? Most people when allowed time to reflect say yes sometimes things happen that are unexplainabble. Your theory requires faith (Ie LEAP FROGGER RELIGION) to accept the trust you have in yourself, your parents, your teachers, society, technology, on and on, including that by some mysterious (miracle) method Ape transitioned to perfect Man in only one mutation? Amazing faith you have! ! But that would be statistically impossible and so you choose to believe anyway by blind faith. That is your religion just as faithful as any in that you don't need the required data to substantiate your theory. Any scientist worth his salt would never believe a story such as yours (earth only ape-man evolution) without the required massive fossil evidence of all the different variations that would have to be there . This is why BOTH evolution and Creationism can both be true. Yes the good spirit evolved (somewhere sometime probably far far away) and then created man! The data is your friend always. Ignoring it is your enemy always. WHERES DEM BONES!! —Preceding unsigned comment added by TripleBatteryLife (talk • contribs)

You mean the transitional fossils? Also, you know that evolution would predict that the current forms of "ape" and "man" are descendants of a common ancestor, not that "current man" descended from "current ape", right (that is, there may not be anything resembling a half-way intermediate between the current forms)? DMacks 04:03, 2 August 2007 (UTC)

Like most of these intelligent designe/creationists - User:TripleBatteryLife doesn't read what people write - and they refuse to answer reasonable questions such as the ones I asked in my previous postings. If this person were to tell us when he/she believes mankind appeared on the scene, we could rationally discuss the nature of the 'gap' into which this event falls...but TripleBatteryLife won't do that because that allows us to apply scientific rigor to this half-baked theory which will immediately cause it to collapse. So instead it's better to keep flinging the same old tire "leapfrogger" nonsense and hope that some of it sticks. I've carefully explained (twice!) why massive quantities of these fossils are not there - the fact of their non-existance is precisely what the theory predicts. We are beyond the point where we need to find new fossils to validate the theory. There are indeed enough fossils around to show quite clearly the stages of evolution between the common ancestor of human and chimp. The case is proven beyond all reasonable doubt - we're just having problems with the unreasonable doubters. I've been accused so far of believing in reverse time travel and that interplanetary travel must be easy because of relativity(!) - which clearly proves that TripleBatteryLife understands very little about mainstream science!

To address the lastest set of bizarre things:

DNA variants would many many many but you have none in quanties needed to validate your theory. OK - this is ungrammatical gibberish - but I think he/she is asking why we don't have DNA evidence. Well, we don't have DNA from fossils because...THEY ARE CHUNKS OF ROCK...no biological material remains in them - so no DNA could be extracted. We DO have evidence of a common ancestor of chimp and man in that mankinds DNA is more similar to a chimpanzee's DNA than that of any other creature. That makes us "close" on the evolutionary tree.

I daresay if you were born in the 1700's you would teach that manned flight was impossible and would never happen because after all your studies didn't teach you that. Well, the first balloon was invented in 1709 - so clearly some people who were born in the 1700's were perfectly able to conceive of the possibility of manned flight. But either way, that has no bearing on this. It's hard to predict what will or will not be possible in the future - but we aren't talking about the future - we're talking about the past. The past is an entirely different matter - we have the evidence.

Can you seriously say that you never had anything spiritual or supernatural happen to you ever ever ever? Most people when allowed time to reflect say yes sometimes things happen that are unexplainabble.' Yes, I can seriously say that never happened to me. Unexplained and unexplainable are two different things. I can't explain how that dog across the street from my window got there - does that make it a spiritual event? No - its "unexplained" but it's not "unexplainable".

Your theory requires faith (Ie LEAP FROGGER RELIGION) to accept the trust you have in yourself, your parents, your teachers, society, technology, on and on, including that by some mysterious (miracle) method Ape transitioned to perfect Man in only one mutation? Amazing faith you have! ! Aaaarrgghhhhhh!!!! Please, PLEASE listen!!!! Neither I nor anyone else who understands evolution ever claimed that ape transitioned into man in one mutation! NEVER! I tell you again - look at the List of hominina fossils - each step from one proto-human to the next entails one or more mutations. We are claiming not one step - but dozens and dozens of steps. The last few steps have happened within recorded history - lactose tolerance for example is believed to have happened within the last few thousand years - and it's not over yet. *IF* we believed this happened in one step - then you'd be right to chastise us for a flakey theory...but that's not what we claim. Many steps - dozens, perhaps hundreds of mutations. OK - so what about 'faith'. Again, No - you misunderstand. It's not faith - it's KNOWLEDGE. I've read Darwins works - I don't believe it because Darwin said so - I believe it because I can follow his reasoning about the Finches and the other examples he comes up with. What he says makes logical sense. I've seen fossils in a museum - I understand how evolution works and I've decided on the basis of that knowledge that this is a perfectly rational explanation that doesn't require magic or other things that have to be accepted without evidence. Even if these "gaps" were such damning evidence against evolutionary theory - what evidence do we have to the alternatives? How do we explain the fossils we do have if mankind "poofed" into existance by magic. How come we don't see other evidence of that?

But that would be statistically impossible and so you choose to believe anyway by blind faith. Sure - a single step WOULD be statistically impossible - and I don't believe that. However, lots of tiny mutations are statistically NECESSARY. When you have a molecule the size and complexity of DNA, it's statistically impossible that it could be copied so many times WITHOUT mutations. Far from being statistically unlikely, the idea that animals DON'T mutate is statistically impossible!

That is your religion just as faithful as any in that you don't need the required data to substantiate your theory . - No - there is a fundamental difference. Religion requires you to take the most bizarre claims on faith "because I say so" (where "I" is a priest or some other nut job). Science requires only that you listen/read the arguments, examine the evidence and believe or not believe on the basis of what you find. It's a totally different modus operandii.

Any scientist worth his salt would never believe a story such as yours (earth only ape-man evolution) without the required massive fossil evidence of all the different variations that would have to be there . -- WHAT?!?! Almost every scientist believes precisely what I've been explaining! Check out (for a silly example) Project Steve.

This is why BOTH evolution and Creationism can both be true. Yes the good spirit evolved (somewhere sometime probably far far away) and then created man! The data is your friend always. Ignoring it is your enemy always. - Creationism (as it is described in the Christian bible for example) is clearly disproved by the fossils of dinosaurs and any number of other early creatures. The Bible says that humans and all other modern animals were created pretty much instantaneously in their present form - probably a few thousand years ago. Science has blown that theory into shreds. Why are there fossils at all? So the Creationists have retreated steadily into smaller and smaller claims in the hope that science cannot disprove them. The latest variation seems to be "Yes, OK, everything evolved...EXCEPT humans...who were placed here by magic". But that's gradually failing too - the reason you won't answer my question "When do YOU believe mankind came into existance?" is because whatever date you pick is problematic because if you pick a very old date - we have zero fossils of modern man at that age - which is impossible to explain - AND we have fossils of more recent (but less man-like) creatures that are more recent than that date. But, on the other hand, if you pick a date that's too recent, then you run the risk that science might find a modern human fossil dating back before then - which would handily disprove your theory. The truth is, no matter what date you pick, the FACT that man has been evolving very gradually means that we can always disprove what you say. So that's why you won't answer my question!

WHERES DEM BONES!! - in the museum where you can go take a look at them. You keep bringing this up over and over again like it was some triumphal claim of correctness - but the quite the reverse is the case. Whilst fossils are rare - we have plenty enough to document the slow evolution from proto-human to human. The important thing is "WHERE IS THE EVIDENCE THAT DISPROVES EVOLUTION" - not one single fossil has ever been found that disproves it. Every one we find slots neatly into the pattern we've established. Each one falls neatly into place. There is no countervailing evidence...not a shred. Point me to one actual FACT (not an absence of a fact - an actual tangiable THING) that disproves evolution. You don't have any because there aren't any. If we found a fossil T-Rex that dated to 1 million years ago - we'd be in deep shit. If we found a human fossil that dated back to 100 million years ago - we'd have a failed theory on our hands. But instead, every new bone that's dug up simply improves on our understanding - When did birds evolve from dinosaurs? Did dinosaurs have feathers? When did endothermy evolve? These are the questions - not "Does this whole thing work or not?"

I doubt you'll answer these (because you havn't answered a single one of the questions I've posed for you previously - despite my politely addressing every single point you make) - but I'll ask anyway:

1. Do you (as a creationist) believe in the idea that generations of organisms can change over time due to mutations in their inherited DNA? (I'm not just talking about man here - any creature or plant?)
2. Do you believe that's also true of humans?
3. Do you believe that if one creature out of a population has some genetic advantage (such as, for example, the ability to digest cows milk as an adult human in a primitive, agrarian society), that this individual is more likely to survive than the others in times of stress (such as a famine due to crop failure) ?"
4. At approximately what date did fully complete 'modern' man appear on the earth according to your theory? I don't need an exact date - plus or minus half a million years is plenty accurate.
5. If you picked a date less than (say) 20 million years ago: How do you explain the existance of fossils before that date?
6. If you picked a date more than 20 million years ago: How do you explain the lack of any human or human-like fossils between 20 million and 5 million years ago?

Honest, calm, on-topic and truthful answers to these questions please. Failure to answer will be regarded as evidence that you are talking nonsense!

SteveBaker 13:06, 2 August 2007 (UTC)

Hey, there, TripleBatteryLife, do yourself and us all a favor. Don't lecture us about science, and we won't lecture you about theology.

There are few things more pathetic than watching an envoy from a faith-based belief system, one who badly distrusts the scientific method and its results, try to use the scientific method in a twisted attempt to disprove its own results.

If you want to believe and have faith in your own hairy thunderer or cosmic muffin, please, do so. But if you want to use logic and the methods of science, you're going to have to learn how to use them properly, and learn why the currently-valid scientific theories are held to be valid. Once you do, you're not going to disprove any of them with a few glib arguments, because those theories have been painstakingly built up over hundreds of years by countless very careful thinkers, and they've already withstood (and been strenghthened by) the myriad counterarguments leveled against them by critics far more clever than you, me, or Steve Baker. If you want to use the methods of science, you're going to have to accept that life as we know it arose through evolution and natural selection, because that's what science today has proven. --Steve Summit (talk) 14:25, 2 August 2007 (UTC)

IS IT 24 hours yet? Am I going to be censored for the 6th time? Wow .. scientists who censor?? Just for forcing those who beleive in the GAP LEAP to accept that they do it on faith? Guess that really gets to them. Truth must be so emotional that they start to squash that which they don't understand! BOTH ARE TRUE! The facts support both! FYI: When you have a child in effect you are now a "creator". You say you believe "time dilation" but don't believe in a good spirit. FYI: "Some" religions believe that time went backwards for something like 14 minutes? I won't tell you where because I might be censored. TripleBatteryLife 15:25, 2 August 2007 (UTC)

It's hard to take people seriously when they fling loaded terms like "censorship" around meaninglessly.

We don't accept evolution based on blind faith; we accept it based on evidence and carefully-constructed rigorous arguments, evidence and arguments which have been presented to you numerous times and which you refuse to accept.

Please don't call it censorship when I suggest you drop the references to time travel. They're immaterial to the argument at hand and they're making you that much harder to take seriously. --Steve Summit (talk) 16:21, 2 August 2007 (UTC)

So you as a scientist are saying that some things are not theoreticallly possible. FYI: Even the defense dept uses Pschics as a tool as do police dept from time to time. I presume you think they are also fools? TripleBatteryLife 17:40, 2 August 2007 (UTC)

TripleBatteryLife is displaying the usual creationist thinking. See, the more transitional fossils found, the more "gaps" there are. If there's an extinct species A and a living species B, if an extinct species C is found to be a transitional fossil, creationists demand more transitions between A to C and B to C. It's ridiculous, honestly. No matter how many transitional fossils are found, creationists are never satisfied. 128.163.245.13 21:03, 2 August 2007 (UTC)

Yes - that was evident from his supposition that we believe that there is one single evolutionary step between "apes" and man. Nothing could be further from the truth - we believe there were hundreds or perhaps thousands of single-gene mutations between the common ancestor of chimps and humans - each change resulted in another step along the way. He thinks there is just one single step - and won't listen when we say otherwise. But that's not such a logical thing. If there was just one single step then he ought not to be demanding a million fossils spread throughout 4 million years - logically, he should be demanding just two fossils - one from the generation just before this sudden change and one from just afterwards. In effect, one fossil of Orrorin tugenensis and one of modern man - dated (let's say) 20 years apart. That would prove conclusively that the change from ape to man happened in one generation. However, that's not what science is claiming - and not what the evidence shows. Instead we see 40 or more separate fossils - each differing from the previous by a small amount...the kind of change that one gene could be responsible for. This fact is beautiful evidence for an evolutionary origin for mankind - and it fits exactly what we are saying. (That's not an accident - we're saying this BECAUSE that's what the fossils are telling us). However, this person does not listen - so he's repeatedly claiming that we scientists believe in time travel, that we think interplanetary travel is easy...all sorts of crazy stuff. In amongst all of those misconceptions is buried the one where he thinks we believe that evolution of man from ape happened in a single step. Why does he believe this? Who knows? I've asked some probing questions in an attempt to discover the root problem...and I don't get any answers. SteveBaker

<sigh> Firstly, I'm against censorship - as I think most scientists are. Free speech is the only way to avoid what the religious nuts did to Galileo Galilei. However, I note that you have not yet answered my questions to you...I really wish you'd take the time to do that. But Creationism isn't true - we're not censoring that view - we're just telling you it's indefensible...scientifically. You may feel free to boldly assert that this is a matter of religion and since God can to anything he wants, he can fake all of the evidence we'll ever find and therefore we can't prove a thing. However, as others have said - you are trying to argue SCIENTIFICALLY for Creationism - and now you have to live by the rules of evidence and proof. The whole debate about the teaching of creationism in schools is not that it shouldn't be taught - but that it shouldn't be taught IN A SCIENCE CLASS - because it's a matter of faith and religion, it needs to be taught in a religious instruction class.

The facts support both! - Which facts support creationism? I'm not aware of any.

FYI: When you have a child in effect you are now a "creator". - That's one meaning of the word. If by "Creationism" you mean "A belief that humans can have children" - then there is no argument. Evolution depends on the fact that animals have baby animals.

You say you believe "time dilation" but don't believe in a good spirit. - What?!? "Good spirit" - what do you mean by that - a bottle of 50 year old Scotch...that's a good spirit and I believe in that! If you mean to imply that time dilation implies a 'spirit world' or some such - then I don't understand how one implies the other at all. Time dilation is easily demonstrated. There are particles that decay very quickly when you make them in the lab - in a billionth of a second, they are gone. We have seen these same particles last for many seconds as they streak into our atmosphere from space at a substantial fraction of the speed of light. Time for those little particles has been 'dilated' - the speed of clocks on earth are running very quickly from their perspective - and our clocks tick by several whole seconds in the billionth of a second it takes them to decay! Time dilation in action! We also have experiments like flying two very precise atomic clocks around the world in jet aircraft heading in opposite directions - then very carefully compared the times on the clocks - and their times disagree to exactly the degree Einstein's math suggested it would. Time dilation (and relativity in general) is a very well proven law of physics.

FYI: "Some" religions believe that time went backwards for something like 14 minutes? - There are all sorts of nuts out there - I don't believe them either. Some people claim to believe in the flying spaghetti monster and the invisible pink unicorn (may Her hooves be forever unshod) - but that doesn't make them true. I won't tell you where because I might be censored. - Why on earth would we censor you for that?!

As for your last point - you are putting words into our mouths again. So you as a scientist are saying that some things are not theoreticallly possible. - We absolutely are saying that some things are not even theoretically possible. Travelling faster than the speed of light, making a perpetual motion machine, simultaneously measuring both the speed and mass of an electron to better than h-bar...all of those things are impossible - both in theory and in practice. There are lots of others.

Even the defense dept uses Pschics as a tool as do police dept from time to time....yes, there are a lot of nut-jobs in the police and defense department too! I've spent a large fraction of my life working with people in the Defense department - and whilst a lot of them are really smart people - they definitely have their share of crazies. But that's true of any group of people you care to name (including scientists) there will always be a handful of of people who's ideas are "off the chart". That's not such a bad thing - so long as they are prepared to debate the point calmly and rationally - listen and answer questions. The problem here is that you are doing neither. So - one more time - please answer my six questions above. Thanks! SteveBaker 21:13, 2 August 2007 (UTC)

Who discovered lathosterol?

Who was the first to discover/isolate lathosterol? What is the origin of the name "lathosterol" (What does "latho" stand for?) Tavilis 17:08, 27 July 2007 (UTC)

Dunno. But it looks like it was discovered around 1950: "...observations on the feeding of cholesterol to guinea pigs supported this concept (Glover, Glover & Morton, 1952). The work was done, however, before the discovery of lathosterol, which is difficult to separate from its isomer cholesterol. It has been shown that lathosterol can be converted into cholesterol in vivo (Cook, Kliman & Fieser, 1954)" [2] Rmhermen 03:47, 28 July 2007 (UTC)

In my Greek dictionary, the words beginning with lath (λαθ) all have to do with forgetting or secrecy, for whatever that's worth. —Tamfang 03:55, 30 July 2007 (UTC)

Magnetic North/South

It is a given that the north pole of a compass needle indicates the direction of magnetic North. Therefore it is North seeking. However if one is in the southern hemisphere, the same compass will still indicate North, is the north pole of the needle North seeking, or, as one would be closer to magnetic South, is the south pole of the needle South seeking?

Both. If you want to think of it that way, one end is always north-seeking and the other is always south-seeking. There's no reason to think only one pole can operate at a time.

If you want to understand it a little deeper, first realize that's there's no such thing as a magnetic pole (that we know of, at least: see magnetic monopole). There is only a magnetic field, and the compass needle aligns itself to that field. —Keenan Pepper 17:54, 27 July 2007 (UTC)

The entire compass needle is acted on by the magnetic field of the earth at all points, not just on one end of it. The N end of a compass needle points to a spot near (but quite a ways from) the Earth's north geographic pole, but which is actually a South magnetic pole. Edison 21:00, 27 July 2007 (UTC)

"...which is actually a South magnetic pole" is a matter of definition. Since there have been no geomagnetic reversals in recorded human history, surely, the North Magnetic Pole is the one nearest to the North Geographic Pole? - the same one pointed to by the lodestones and floating needles of ancient mariners who labelled the end that pointed north as North. Astronaut 16:05, 29 July 2007 (UTC)

Like magnetic poles repel each other, opposites attract; hence the magnetic pole in the northern hemisphere must be opposite to the point marked "N" on a compass. Physicists could have adopted the convention that the latter is a south magnetic pole, but didn't. —Tamfang 04:10, 30 July 2007 (UTC)

Newton's Third Law of Motion

I was reading Physics for Dummies and in the section about Newton's Third Law of Motion, it talked about how for a car to move, the road needs to exert as much force against the tires as the tires exert on the road. It goes on to say:

"So why doesn't the road move? After all, for every force on a body, there's an equal and opposite force, so the road feels some force, too. You accelerate...shouldn't the road accelerate in the opposite direction? Believe it or not, it does: Newton's law is in full effect. Your car pushes the earth, affecting the motion of the earth in just the tiniest amount. Given the fact that the earth is about 6,000,000,000,000,000,000,000 as massive as your car, however, any effects aren't too noticeable."

Is this actually true? -- Zealz 19:59, 27 July 2007 (UTC)

Yes. 151.152.101.44 20:00, 27 July 2007 (UTC)

Yes, If you stand on the ground it has to push up equally in order to keep you from falling through the same principle applies to moving objects that exert force onto the ground in order to move. If your car gets stuck in the mud that is because the ground can not exert enough force(through friction) on the tires to get your car moving.--64.40.88.131 20:16, 27 July 2007 (UTC)

Absolutely true, and fascinating! An other example I love is the following: when you jump up, the Earth provides the force necessary for you to rise, however, due to action and reaction, you exert the same force on the Earth, and it is actually pushed away from you. However, just as it says in the article, the Earth is 100,000,000,000,000,000,000,000 (10^23) times heavier than you, and while you jump up around a meter, the Earth moves such a small distance that it is simply not measurable... --Waldsen 04:01, 28 July 2007 (UTC)

As the old saying goes, the Earth weighs 150 pounds in my gravitational field. Bathroom scales work just as well upside down (except that you can't read the display). But note that your actions on the surface of the Earth can't cause any long-term deflection in its orbit, not even by a tiny bit, because they don't affect the center of mass of the Earth-you system. -- BenRG 00:47, 29 July 2007 (UTC)

You can point a flashlight directly into the sky. It will move the earth permanently.

dairy cow slaughter weight

About how much does a mature dairy cow weigh at slaughter? ike9898 21:07, 27 July 2007 (UTC)

There is more than one breed of cow that is used in dairying, so it would depend. [3] says a Jersey averages 900lb, but the range is wide, 800-1200lb. While many dairy cows are sent to slaughter beacause of age and falloff in production (which would imply a lower weight) many are slaughtered to regulate the supply of dairy products and thus prices so the average weight for a breed is probably not far off from the average weight of the cow when slaughtered. 161.222.160.8 23:08, 27 July 2007 (UTC)

It weighs exactly 1 whole stein. Duh. -- Azi Like a Fox 00:33, 29 July 2007 (UTC)

Blood glucose monitoring

A family member has recently started having to check his blood glucose level, with one of those electronic meters and monitoring strips. When he gets a new package of monitoring strips, he has to make sure that the meter and the monitoring strip have the same "code". What purpose does that code serve, and why do different packages of strips have different codes? Why can't the manufacturer make monitoring strips that all have the same codes? Corvus cornix 22:28, 27 July 2007 (UTC)

calibration perhaps (i.e. setting the correct zero point)? Flyguy649 ^talk _contribs 23:18, 27 July 2007 (UTC)

This patent abstract explains the calibration code concept in some detail. The Glucose_meter#Characteristics section also provides some explanation - hydnjo talk 02:25, 28 July 2007 (UTC)

Thanks to both of you. Corvus cornix 03:59, 28 July 2007 (UTC)

Back when cameras used film, the film came in a variety of "speeds." Setting the film speed into an automatic exposure camera correctly meant that it gave the right exposure. Manufacturing variation in the sensitivity of the test strips means that without the coding the inaccuracy would be greater than when the strips are correctly coded into the tester. Ideally the manufacturer would have quality control such that coding is unnecessary, or the strips would tell the meter their codes automatically, like some modern film cameras can automatically sense the film speed. Edison 05:52, 28 July 2007 (UTC)

And this patent extract describes the machine readable calibration code that Edison mentions above. Interestingly, the abstract also gives some clues as to why the codes are necessary in the first place. - hydnjo talk 10:31, 28 July 2007 (UTC)

It still boils down to the inability of the manufacturers to adequately control the strip manufacture so that the strips all work the same in the meter. An alternative would be to increase the cost by rejecting those which fall outside a narrow tolerance band. If a user happens to switch vials of the test strips and the coding is not for the present vial, the results can be off substantially more than if there were one tolerance band for the strips and the manufacturing was calibrated to conform. Coding allows for poor quality control in the mass production of the strips. When they apparently charge 75 cents or a dollar for some of the strips, it seems pretty obvious to spend a fraction of a cent and add a calibration mark on the strip to be resd by the meter. Edison 16:35, 28 July 2007 (UTC)

Agreed but life is full of compromise. The current state of test strip manufacturing capability, even with calibration codes, still has a +/- 10 to 15% error band when compared to a lab analysis of blood glucose in a blood sample. - hydnjo talk 17:28, 28 July 2007 (UTC)

The Equator

I encountered a curiosity, and it seems appropriate as a Science question. Take the entire population of the earth at the present moment. Have each and every person stand side by side. They are standing on the equator and, thus, forming a "line of people" (a circle) that circumnavigates the globe (at the equator). The question is: how many times will that line "wrap around" the globe, if you need to have every person participate? (Assume that people can "stand" along every portion of the equator -- including oceans, mountains, etc.) Thanks. (JosephASpadaro 23:02, 27 July 2007 (UTC))

I figured the average shoulder breadth to be 2ft. At a population of 6 billion that is 12 billion feet of shoulder. The equator is 24901.5 mi long, which is 131,479,920ft. Divide the first by the second and I get 91.26 times. Growing all the time though. 161.222.160.8 23:17, 27 July 2007 (UTC)

6 billion! That is so 7 years ago! While I've been typing this message, the "world population clock" estimate at census.gov has ticked past 6,608,000,000. Which means that if 161's other numbers were precisely accurate, the answer to Joseph's question would be 100.517+. Of course, "about 100" is really about as accurate as can reasonably be said. --Anonymous, July 28, 2007, 02:57 (UTC).

If they would stand breast to back and assuming they are on average 20 cm 'deep', that would be a ribbon of 20 m. On a half circumference of roughly 20,000 km that would mean we occupy only one millionth of the surface of the Earth (of course that is not entirely correct because the Earth isn't a cylinder, but it's only meant as a rough indication). And assuming an average height of 2 m, on a thickness of the atmosphere of 100 km that's 1/50,000 in height. Combined, we occupy only 1/50,000,000,000 (one 50 billionth) of the atmosphere. And the atmosphere is just a tiny layer around the Earth, which has a radius of 6,000 km, so that's 1/60th, so we occupy 1/3,000,000,000,000 (one 3 trillionth) of the Earth. And that's for all 6 billion (+) of us, which gives you an idea of how puny we are as individuals, compared to the Earth - 1/20,000,000,000,000,000,000,000. I won't extend these calculations into space. :) DirkvdM 05:51, 28 July 2007 (UTC)

20 cm x 6,000,000,000 = 20 m (2,000 cm)? What? Skittle 12:44, 29 July 2007 (UTC)

Clarifying what I believe DirkvdM means with the 20cm estimate: In the original calculations, we have people standing shoulder to shoulder, and this wraps 100 times. That means, everybody is standing in a rank of 100 people, breast to back, stretching 20m / 2 = 10m on each side of the equator./85.194.44.18 18:55, 29 July 2007 (UTC)

Ah, that makes more sense. It seemed a little odd. Skittle 23:15, 29 July 2007 (UTC)

Average height 2m? What world do you live in? :-P N.B. As with a recent question re: human weight (mass), a lot of people seem to be forgetting that many of the 6.8 billion or whatever are children and many are also in developing countries in relatively poor health so the averages are probably an overestimate Nil Einne 15:49, 28 July 2007 (UTC)

Like I said, it was meant as a rough indication. DirkvdM 07:58, 29 July 2007 (UTC)

20cm x 6,600,000,000 = about 33 times round the equator.

Incidentally, I suggest taking a peek at John Brunner's novel Stand on Zanzibar. Astronaut 16:20, 29 July 2007 (UTC)

I think a much more satisfying project would be to convince the population of the United States (~ 300,000,000) to stand on each other's shoulders (~ 1.5 m) and thereby be 450,000 km tall, which is high enough to touch the Moon. --TotoBaggins 14:15, 30 July 2007 (UTC)

might work if we built it from the moon down --froth^t 14:54, 30 July 2007 (UTC)