Wikipedia:Reference desk/Archives/Science/2012 September 22
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September 22
[edit]Undersea river system 100-200 miles southwest of Ireland
[edit]![](http://upload.wikimedia.org/wikipedia/commons/thumb/9/94/Porcupine_Biscay_canyons.png/220px-Porcupine_Biscay_canyons.png)
See this pic: [1]. What caused that river system ? Was it formed when it was above sea level ? StuRat (talk) 00:03, 22 September 2012 (UTC)
- That area is called the Porcupine Seabight; the "river system" is called the Gollum Channel. Our article on submarine canyons discusses how features like that form -- I can't see that there is any specific information about this one in particular. Looie496 (talk) 00:37, 22 September 2012 (UTC)
- Thanks, looks like there are several theories but they aren't quite sure. StuRat (talk) 02:20, 22 September 2012 (UTC)
- What are the depths at the top and bottom of the Gollum Channel ? StuRat (talk) 16:55, 22 September 2012 (UTC)
- If you can, you should look at this in Google Earth. It shows the sea bottom features and the depth at each location. Looie496 (talk) 17:09, 22 September 2012 (UTC)
- The Gollum channel system is currently inactive (or only slightly active) [2] and has been in that state for the whole Holocene, so it may well have been created during the last ice age when sea levels were lower (but not the hundreds of metres lower that would be required for it to have started sub-aerially) - the upper end of the channel system is at least 300 m deep. Mikenorton (talk) 17:20, 22 September 2012 (UTC)
Was the Gollum Channel named for Gollum/Sméagol? I tried googling but failed to find the answer... Pfly (talk) 05:49, 23 September 2012 (UTC)
- Yes it was [3] - in the area at the southern end of the Rockall Plateau and Porcupine Bank, there are a number of features that have a 'Middle Earth' connection, including Fangorn Bank, Edoras Bank, Gandalf's Spur, Lorien Knoll, Rohan Seamount, Gondor Seamount and Isengard Ridge [4][5]. Mikenorton (talk) 13:29, 23 September 2012 (UTC)
OK, thanks for the answers, all. StuRat (talk) 20:36, 25 September 2012 (UTC)
![](http://upload.wikimedia.org/wikipedia/en/thumb/f/fb/Yes_check.svg/20px-Yes_check.svg.png)
Bread hardening in open air
[edit]I've noticed that when I leave a slice of bread out in open air on the dinner table, the bread will harden within a few hours. However, if I keep bread inside a semi-sealed bag, even if that bag is not quite air tight (say, tied with a loose twist tie or rubber band), the bread will stay soft for days. Why? —SeekingAnswers (reply) 07:45, 22 September 2012 (UTC)
- The evaporation of moisture from bread is what makes it stale. This happens rapidly in open air, and more slowly in a semi-sealed bag, since evaporated water from the bread soon fills the bag with water vapor, preventing further evaporation. You might also notice that the part of the bread near the opening goes stale first, since water vapor escapes there.
- You can do an experiment. Put a bit of water on a plate, and put the same quantity in the same type of semi-closed bag you used for the bread. Notice how long it takes each to evaporate. StuRat (talk) 09:04, 22 September 2012 (UTC)
- Earlier today I read the bread also hardens by starch recrystallization. You can ask the question why does moisture make the product softer. It does this too for paper. Graeme Bartlett (talk) 10:51, 22 September 2012 (UTC)
- That water makes something softer doesn't seem all that surprising. Unless it's below freezing, water is a liquid, and liquids are "less hard" than solids. So, the more liquid you have mixed in, the less hard it will be. This also is generally true of other liquids, like oils. There may be exceptions, of course, where the liquid reacts with the solids in some unusual way. StuRat (talk) 16:54, 22 September 2012 (UTC)
- You are correct; It's a common misconception that bread goes stale simply as a result of losing moisture. In reality, staling is a product of how much moisture is trapped within the starch and the degree to which said starch has thus crystallized, not just the overall moisture content of the bread. Of course bread can also dry out entirely, but a very moist loaf can still have an incredibly hard consistency under many conditions. The popular method of trying to keep bred fresh by placing it in a refrigerator is actually counter-productive since the low temperatures accelerate the crystallization. And though some of the storage factors discussed above will have an effect on the rate of staling, often the more determinative factor will be the nature of the starches used in the bread in question. Snow (talk) 23:48, 22 September 2012 (UTC)
Land reclamation
[edit]Are there any serious proposals for drying up the Mediterranean by repeating the Messinian salinity crisis? That would free up a lot of land for human habitation, and since Europe is the most densely populated and wealthiest continent, it seems that there would be powerful incentives to do this. --140.180.242.9 (talk) 07:46, 22 September 2012 (UTC)
- Not quite the same thing, but Atlantropa is similar in principle, and that article is an interesting read. Evanh2008 (talk|contribs) 07:52, 22 September 2012 (UTC)
- I don't know that there's all that much impetus for the OP's proposal. On the whole, Europe is densely populated, but the population levels have plateaued in most European countries, see List of countries by population growth rate. Also, Europe has lots of middle-to-large cities, but almost none of the "super large" cities one finds in the developing world. Notice how few European cities appear at List of urban areas by population. Moscow is 15, Paris is 25, and London is 34 on that list. Also, European cities are well designed and well managed, as Europe has the money to do so, European cities have, comparatively, better public infrastructure. So, with Europe, you have a case where the continent isn't growing that fast, if at all, the cities are smaller, on average, and they are well designed to deal with the populations they have. See also Demographic-economic paradox for some background information. --Jayron32 13:03, 22 September 2012 (UTC)
- It's one way to solve the global warming crisis. Or at least make it seem insignificant compared the the new problems :-); adding 3300 km3 of water (data from "The Great Soviet Encyclopedia") to the oceans each year means an extra 9 mm rise in sea levels added to the current 3 mm/year rate. That will slow down eventually, with less evaporation and phttp://en.wikipedia.org/w/index.php?title=Wikipedia:Reference_desk/Science&action=submitossible droughts in Europe. Haven't looked at the land gains and losses, but I suspect the balance won't be positive. I'd still vote in favour if it could be accomplished in my lifetime. Must be a spectacular view. But the rate will only be about 1.3 meters per year. Ssscienccce (talk) 14:39, 22 September 2012 (UTC)
- I don't know that there's all that much impetus for the OP's proposal. On the whole, Europe is densely populated, but the population levels have plateaued in most European countries, see List of countries by population growth rate. Also, Europe has lots of middle-to-large cities, but almost none of the "super large" cities one finds in the developing world. Notice how few European cities appear at List of urban areas by population. Moscow is 15, Paris is 25, and London is 34 on that list. Also, European cities are well designed and well managed, as Europe has the money to do so, European cities have, comparatively, better public infrastructure. So, with Europe, you have a case where the continent isn't growing that fast, if at all, the cities are smaller, on average, and they are well designed to deal with the populations they have. See also Demographic-economic paradox for some background information. --Jayron32 13:03, 22 September 2012 (UTC)
- I am not sure how attractive living on below-see level salt pans next to a dead sea would be. See Dead Sea and Death Valley. (Note the ongoing theme?) μηδείς (talk) 17:22, 22 September 2012 (UTC)
- Having recently returned from the Costa del Sol, I'd agree with that. That part of Spain has no particular shortage of land - the only really crowded parts of the area are caused by the eagerness to build within ten miles of the sea. Take away the sea, and the land basically becomes worthless. The only places that I can imagine really benefitting would be places like Gibraltar, which is strongly affected by its extreme lack of land (small-scale land reclamation projects from the Mediterranean were still ongoing when I was there). --Demiurge1000 (talk) 17:58, 22 September 2012 (UTC)
- Guess I'm not much of a humanitarian, valuing aesthetic considerations over the welfare of people ;-) Ssscienccce (talk) 09:44, 23 September 2012 (UTC)
- Having recently returned from the Costa del Sol, I'd agree with that. That part of Spain has no particular shortage of land - the only really crowded parts of the area are caused by the eagerness to build within ten miles of the sea. Take away the sea, and the land basically becomes worthless. The only places that I can imagine really benefitting would be places like Gibraltar, which is strongly affected by its extreme lack of land (small-scale land reclamation projects from the Mediterranean were still ongoing when I was there). --Demiurge1000 (talk) 17:58, 22 September 2012 (UTC)
- The sea works as a temperature equalizer, is used for fishing, it's a hold back for the wildlife of Africa to spread diseases, and so on. Not a good idea, I would say. Electron9 (talk) 21:35, 22 September 2012 (UTC)
- Our article says it took 1,000 years last time. Even without the undesirable side effects others have mentioned, there is no way to know what is going to happen to the human race over the next 1,000 years to know if extra land would be of any benefit. --Tango (talk) 22:28, 22 September 2012 (UTC)
- The premise is silly. Europe is not so crowded compared to SE Asia. And there's plenty of room for skyscrapers and upward cities in Europe. Not to mention its below replacement rate birth rate. Muslim and other foreign investors will be building skyscrapers there soon enough, see the London penis building. μηδείς (talk) 05:04, 23 September 2012 (UTC)
The inhabitants of doggerland should have built dykes and pumping stations to deal with rising sea levels. Count Iblis (talk) 17:37, 23 September 2012 (UTC)
American squirrel behavior
[edit]Since the beginning of August, I've lived in a small house in Indiana with concrete block walls and a slab foundation; except for a garage door on the front (which doesn't lead anywhere, as behind it is the same kind of walls as everywhere else), I have horizontal siding that starts a couple of feet above the ground and rises as far as the roofline. While it doesn't happen every day, I'm often awakened (including today) by the sound of something worrying at the side of the house that has no doors; on the one occasion when it was at the front of the house, I stepped out and saw a squirrel (can't remember what kind) suddenly jump up from exactly where the sound was originating and run off. I didn't see its actions against the wall, so I can't suggest exactly what it was doing, although I'm guessing from the sound that it's doing something at the bottom of the siding. Can anyone imagine why this is going on, e.g. why the squirrel would be doing this? I live in a wooded area, if that matter at all; I've never noticed this in previous residences in towns, even though there were plenty of squirrels around. Nyttend (talk) 12:54, 22 September 2012 (UTC)
- Hmm, this isn't a common meaning of worry; I mean something like OED 8.a, "To advance or progress by a harassing or dogged effort; to force or work one's way through." I'm imagining the squirrel just beating at the siding with paws time and time again, as if it could dig through the siding with enough beats. Nyttend (talk) 13:01, 22 September 2012 (UTC)
- Could it be burying food (or pretending to)? This is the time of year, when there's a surplus of nuts and acorns, for squirrels to stash stuff for winter. -- Finlay McWalterჷTalk 13:51, 22 September 2012 (UTC)
- I think that's a good guess. It also may be looking for a warm, dry place to overwinter. The house next-door to me currently has a drey [6] inside its walls. The fact that you live in a wooded area just means there are more squirrels, and competition for good sites is more intense. SemanticMantis (talk) 14:28, 22 September 2012 (UTC)
- Sticking with the "hiding it's nuts" theory, is it possible the bottom of the siding can be pulled back, a nut can be placed inside, then the siding snaps back, holding the nut in place ? If so, the squirrel may have stored quite a few nuts there. If this is the case, you should remove any nuts (throw them out, where the squirrel can't find them again and put them back). The siding should be better secured and squirrel repellent should be sprayed around the area: [7]. Any gaps under the bottom of the siding should be filled in (although some space may be needed for drainage). StuRat (talk) 16:44, 22 September 2012 (UTC)
- Is the siding made of wood? Squirrels sometimes gnaw on or through wooden boards too... 66.87.127.50 (talk) 04:38, 24 September 2012 (UTC)
Real life applications of chaos theory
[edit]What are they? OsmanRF34 (talk) 13:22, 22 September 2012 (UTC)
- Have you read Chaos_theory#Applications? It lists many applications, most of which are referenced. Some of the applications are even "real life", e.g. electrical circuits. There are also many applications of chaos theory for industrial mixing processes, see e.g. this guy's research [8] SemanticMantis (talk) 14:23, 22 September 2012 (UTC)
- I needed concrete example, and not about something that was explained by chaos theory, but something that was solved by it, in the same way as differential equations can solve lots of problems. OsmanRF34 (talk) 14:41, 22 September 2012 (UTC)
- To quote the noted article, "Chaos theory is currently being applied to medical studies of epilepsy, specifically to the prediction of seemingly random seizures by observing initial conditions." That is, it's a case of making predictions of future things in real life, not merely noting that previous occurrences or an existing dataset are chaotic. DMacks (talk) 14:59, 22 September 2012 (UTC)
- Oh, ok. I think my last link qualifies as making predictions and solving real world problems. There is also chaotic encryption [9]. SemanticMantis (talk) 15:16, 22 September 2012 (UTC)
- That's a
crackpotsnake oil site. I suppose all encryption is chaotic in some sense, though. -- BenRG (talk) 18:44, 22 September 2012 (UTC)
- That's a
- Chaos theory has solved the problem of making money for proprietary traders=P.Smallman12q (talk) 20:02, 22 September 2012 (UTC)
- Oh,those guys are crackpots? How about these guys [10], [11]? The latter is from IEEE transactions, a thoroughly reputable journal... I don't know if/when it would ever be deployed in the real world, but there is and has been serious, rigorous scientific interest in using chaos theory to design secure communication schemes for various applications. (Smallman, I removed your outdent to make it clear who I was replying to.) SemanticMantis (talk) 22:26, 22 September 2012 (UTC)
- All of your links point to the same place, but I looked around for more information. The page you linked mentions a 1998 paper by Baptista which seems to be the basis for a lot of this work. I couldn't find the paper for free online but the idea is described in cs/0402004. Anyone with any background in cryptography would immediately see that this approach is hopelessly insecure. I'm amazed that it was published and that anyone would think it was a useful basis for further work. The World War II ciphers were already a lot better than this.
- I also found an item by Bruce Schneier about a paper of this type that was published in Nature.
- There is something chaotic about ciphers inasmuch as they try to make all output bits depend on all input bits in an unpredictable way, but they're not chaotic in the sense of being based on chaotic dynamical systems. -- BenRG (talk) 04:39, 23 September 2012 (UTC)
- Ouch, he rips it apart. In a way more damning for Nature, New Scientist, Science News and others that have reported it. Ssscienccce (talk) 12:59, 23 September 2012 (UTC)
- Oh,those guys are crackpots? How about these guys [10], [11]? The latter is from IEEE transactions, a thoroughly reputable journal... I don't know if/when it would ever be deployed in the real world, but there is and has been serious, rigorous scientific interest in using chaos theory to design secure communication schemes for various applications. (Smallman, I removed your outdent to make it clear who I was replying to.) SemanticMantis (talk) 22:26, 22 September 2012 (UTC)
- Sorry about that, I meant to link this paper [12] on arXiv, titled "Adaptive synchronization of coupled chaotic oscillators", and this paper from IEEE [13], titled "A New Approach to Communications Using Chaotic Signals." These both are most certainly using chaotic dynamics, but I will have to read the papers you've linked above to see if they fall under the same category. Anyway, I heard about this stuff when it came out, in the context of it being an interesting real-world application of chaos theory. I confess I have not kept up on the subject, so thanks for pointing out some critical work. SemanticMantis (talk) 14:38, 23 September 2012 (UTC)
This http://www.springer.com/mathematics/dynamical+systems/book/978-0-387-20229-7 is the book if you want to study Chaos and or Fractals. μηδείς (talk) 04:58, 23 September 2012 (UTC)
ISS re-supplying
[edit]The first supply flight to the ISS of a Dragon cargo spacecraft will only deliver 500kg, while Jules Verne ATV delivered 2300kg and Edoardo Amaldi ATV delivered 6600kg the Progress (spacecraft) deliver 2300kg. If you calculate what delivering 1kg costs is spaceX really cheaper than the two other transport options. I could not imagine that 10 Falcon 9 launches are the same price like a Ariane 5 ore three Soyuz rocket. --Stone (talk) 13:24, 22 September 2012 (UTC)
- Are you asking a question? If so, what is it? I can't understand what you want us to help you understand. Nyttend (talk) 13:30, 22 September 2012 (UTC)
- It looks like Dragon can carry up to 6000 kg payload, which seems to make it a much better deal. I'm not sure why they're not loading it up full for this flight. Maybe they want something with less inertia in space while it's still pretty new (I'll see if I can find any references on it). Anyway, 6000 kg's a lot more than Progress can handle, and only somewhat less than an ATV. It also has the capability to safely return material to Earth, which neither Progress nor an ATV have. Buddy431 (talk) 13:38, 22 September 2012 (UTC)
- Oh, as for costs, we do have Comparison_of_orbital_launch_systems which gives the Ariane 5 as costing about 4 times as much ($220 million vs. $56 million), for twice the payload to LEO (these presumably don't take into account the cost of the payload itself, so both will cost somewhat more when you factor in Dragon/ATV). It's harder to find information about how much it costs to launch a Progress spacecraft, but this suggests maybe $20-50 million per launch which includes both the launcher and the spacecraft itself). The low end of that would be extremely competitive on a per kg basis with both Dragon and an ATV, though the ATV has the advantage of the sheer mass of stuff that it can haul into space, and Dragon has the advantage that it can also return supplies safely to Earth. Buddy431 (talk) 14:01, 22 September 2012 (UTC)
- Link about that downmass. And it seems logical that NASA would prefer to spend money on American technology instead of financing other countries space program. Ssscienccce (talk) 14:53, 22 September 2012 (UTC)
- Oh, as for costs, we do have Comparison_of_orbital_launch_systems which gives the Ariane 5 as costing about 4 times as much ($220 million vs. $56 million), for twice the payload to LEO (these presumably don't take into account the cost of the payload itself, so both will cost somewhat more when you factor in Dragon/ATV). It's harder to find information about how much it costs to launch a Progress spacecraft, but this suggests maybe $20-50 million per launch which includes both the launcher and the spacecraft itself). The low end of that would be extremely competitive on a per kg basis with both Dragon and an ATV, though the ATV has the advantage of the sheer mass of stuff that it can haul into space, and Dragon has the advantage that it can also return supplies safely to Earth. Buddy431 (talk) 14:01, 22 September 2012 (UTC)
- To fill a capsule for 6000kg with less than 10% 500kg for the first official mission looks strange. But the previous demo mission transported 525 kg so what is the improvement? 1ATV 2300kg 2ATV 6600kg doubling the payload.--Stone (talk) 19:30, 22 September 2012 (UTC)
- Maybe the limit was the volume of the cargo, not the weight. 600 kg of electronics might have the same volume than 6000 kg of water supplies. Ptg93 (talk) 22:28, 22 September 2012 (UTC)
- Remember too that this is a development effort. The end goal is for the Dragon to be able to deliver crew to and from the station. Because this is a development program for that goal, it does not have to be cost-competitive with cargo systems that are not capable of delivering human beings.--Srleffler (talk) 01:33, 24 September 2012 (UTC)
- The contract they have is to re supply ISS to make it human rated is a development of SpaceX and not part of this deal, I thought. --Stone (talk) 09:30, 24 September 2012 (UTC)
- I just noticed that our article on SpaceX CRS-1 says that the recent launch had an "engine out" condition, where "one or more" (according to the article) of the rockets in the first stage is shut down and the rest pull off a successful mission anyway. It occurs to me (but I don't actually know) that the lighter the payload, the more rockets might be shut down and still leave sufficient thrust. Just adding this thought to the archive in case someone wants to pursue it later... Wnt (talk) 21:41, 8 October 2012 (UTC)
The Worst Mistake in the History of the Human Race?
[edit]I read an essay by Jared Diamond, The Worst Mistake in the History of the Human Race, which argues that human health and livelihood declined after the introduction of agriculture. What's the consensus on his conclusion? 74.15.136.9 (talk) 16:25, 22 September 2012 (UTC)
- Too soon to tell? AndyTheGrump (talk) 16:31, 22 September 2012 (UTC)
- I think it's true that early on agriculture had many negatives, like land erosion, but we later learned to overcome those and yet benefit from the greatly improved food supply. Similarly, the industrial revolution had many immediate negatives, like serious pollution problems, but we later learned to deal with those. StuRat (talk) 16:36, 22 September 2012 (UTC)
- "the industrial revolution had many immediate negatives, like serious pollution problems, but we later learned to deal with those". Citation most definitely needed. [14] AndyTheGrump (talk) 16:41, 22 September 2012 (UTC)
- Your link is to our global warming article. While a potential problem, keep it in perspective. Global warming isn't likely to be so much of a negative as to mean we would be better off without industrialization. StuRat (talk) 17:20, 22 September 2012 (UTC)
- I hope you are right. I see no reason at assume that you are. AndyTheGrump (talk) 17:23, 22 September 2012 (UTC)
- Are you thinking of a scenario where Earth ends up uninhabitable, like Venus ? StuRat (talk) 20:54, 22 September 2012 (UTC)
- There is a lot to worry about that falls far short of that consequence. Personally, I worry about the Earth's average temperature rising a few degrees and sea level rising a dozen feet, causing massive ecological damage and disruption of agriculture and the economy. The Earth need not become uninhabitable for global warming to turn out very badly for us.--Srleffler (talk) 01:45, 24 September 2012 (UTC)
- That doesn't sound so bad as to mean the industrial revolution was a mistake. We just need to move inland a bit and adjust for the new weather. Over the course of decades or centuries, this is doable. StuRat (talk) 04:37, 24 September 2012 (UTC)
- I agree—not enough to make the whole industrial revolution a mistake, and there are undoubtably workarounds and adjustments, although it will almost certainly be cheaper to adjust in advance to prevent global warming than to attempt to adjust after the fact.--Srleffler (talk) 16:20, 26 September 2012 (UTC)
- I don't think it can be stopped, only delayed and reduced. StuRat (talk) 21:55, 26 September 2012 (UTC)
- BTW, your link doesn't work. StuRat (talk) 16:37, 22 September 2012 (UTC)
- [15]. In the modern world, agricultural societies, including very poor agricultural societies, have a longer life expectancy than modern hunter-gather groups. However, the difference isn't that big for poorer agricultural populations. The pastoral societies studied actually have a shorter life expectancy than the hunter-gather groups. Remember too that modern hunter-gatherer societies are probably living in much more marginal land than would have been the norm 12 thousand years ago. If we take life expectancy as a proxy for quality of life, then the move to agriculture probably was initially a bad move, though it appears that for many people, the benefits of agriculture are now manifesting themselves. Buddy431 (talk) 16:50, 22 September 2012 (UTC)
- Emphasis on the modern hunter-gatherer groups. Diamond's argument (at least, he makes the same one in Guns, Germs, and Steel) is that agricultural societies initially had much, much poorer health that hunter-gatherer ones. But they eventually became somewhat entrenched and had the pooled resources necessary to push the hunter-gatherers out of their ranges, which flipped the situation. Comparing modern agricultural societies to modern hunter-gatherers doesn't really address Diamond's point. What you'd want to do is compare modern agricultural societies (that is, nearly all of modern humanity) to hunter-gatherers prior to their being forced out by agricultural societies. I think you'd still find that Diamond's observation holds true — most people in the world are not living especially well, and even those who are in the very rich societies have tremendous systemic health issues that would be avoided if they spent most of their days engaged in physical activity, eating nothing but what can be found growing around them. But it's not all about health — I wouldn't want to be a hunter-gatherer even if it did add a few years to my life. I like things like computers and movies and large urban cores and science. You don't get those with hunter-gatherer societies, because their organizational size is fundamentally limited, and so therefore are their capabilities. --Mr.98 (talk) 19:09, 22 September 2012 (UTC)
The argument is somewhat tongue-in-cheek. In hunting and gathering societies, the less physically fit simply die, as do the excess children and elderly when times are bad, leaving the healthy young physically fit adults. In an agricultural society, the fat and the short-sighted and the excess children can live to unhealthy adulthood and die wracked by arthritis and gout. (Think also how fit and good looking everyone was in Logan's Run.) It's the difference between what is seen and what is unseen. μηδείς (talk) 16:56, 22 September 2012 (UTC)
- There will never be consensus on the worst mistake in the history of human race. We are all way too different in our views on the ideal situation for mankind. Furthermore, if "we" wouldn't have started with agriculture, how else would we have solved the problem of hunger? By killing each other? Lova Falk talk 17:47, 22 September 2012 (UTC)
- Remember that not all hunter-gatherer societies were particularly healthy (even on this level) before the development of agriculture. Excavations at Glacial Kame archaeological sites (Great Lakes region of the USA, several thousand years ago) have shown that adults generally died around age 40, and they were definitely pre-agriculture. Nyttend (talk) 00:51, 23 September 2012 (UTC)
- Yes, but they died fucking buff, dude. μηδείς (talk) 04:55, 23 September 2012 (UTC)
- Remember that not all hunter-gatherer societies were particularly healthy (even on this level) before the development of agriculture. Excavations at Glacial Kame archaeological sites (Great Lakes region of the USA, several thousand years ago) have shown that adults generally died around age 40, and they were definitely pre-agriculture. Nyttend (talk) 00:51, 23 September 2012 (UTC)
The worst mistake in the history of the human race was the Aristotelian rejection of the completed infinite, in favor of the potential infinite. Glad I could clear that up for you all. You may return to what you were doing. --Trovatore (talk) 20:20, 22 September 2012 (UTC)
- No, the worst mistake in the history of the human race was New Coke. --Jayron32 04:52, 23 September 2012 (UTC)
- With honorable mention for the Titanic, the Edsel, and Wendell Wilkie. ←Baseball Bugs What's up, Doc? carrots→ 01:18, 25 September 2012 (UTC)
- I am sorry, Trovatore, but that's just words without ideas behind them: What nature is, then, and the meaning of the terms 'by nature' and 'according to nature', has been stated. That nature exists, it would be absurd to try to prove; for it is obvious that there are many things of this kind, and to prove what is obvious by what is not is the mark of a man who is unable to distinguish what is self-evident from what is not. (This state of mind is clearly possible. A man blind from birth might reason about colours.) Presumably therefore such persons must be talking about words without any thought to correspond. - Aristotle's Physics Book 2, chapter 1
- Not at all, Medeis (you forgot to sign, by the way). Completed infinite totalities are real objects existing independently of our reasoning about them or the words we use to describe them. See mathematical realism. --Trovatore (talk) 21:53, 23 September 2012 (UTC)
- Dangerous "zero" would appear frequently in circulation of numbers such as p-addic number, numebers which completes, in some sense.
While Jared Diamond's methodology is not considered dangerously suspect by historians, Diamond's conclusions have been heavily criticised as being tendentious. Diamond appears to serve controversy above historicity; and, I would suggest that any of Diamond's opinions regarding quality of life should be interrogated for Western imperialism. I would not suggest you believe Diamond's opinions without engaging in the literature of experts critiquing both his methodology and his judgemental conclusions. Fifelfoo (talk) 05:00, 23 September 2012 (UTC)
- I'm not sure "you should read a bunch of unspecified books before considering this question" is really a very useful reference desk answer. At least, if I went to a library, and asked a question, and they responded by saying, "dude, you really ought to survey an entire literature of experts before trying to think about this question," I wouldn't be very impressed. --Mr.98 (talk) 18:15, 23 September 2012 (UTC)
- I really don't know how to supply a relevant answer regarding verifying the truth of a controversial large scale synthetic history's normative judgements regarding an evidentiary dataset that is the interpretation of physical remains rather than the interpretation of literary texts. It is outside of my evidentiary experience, and Diamond makes unique claims at the edge of what I perceive to be the boundary of potentially valid claims. Apart from buttressing "Just so" stories about European imperialism (as in Guns Germs and Steel), I'm not sure what his publications are actually useful for other than to drive back into the research programmes of the people doing actual interpretive work with physical remains. Diamond's questions are in themselves controversial, due to the difficulty in demonstrating them adequately; and, I'd suggest his judgements are only really respected for their resonance with the feelings already held by their readers rather than for the explanatory power of his argument which is difficult to take because of Diamond's textual distance from the analysis of primary source material. Given the controversy, just reading book reviews of Diamond wouldn't really help you to be able to make judgements regarding the validity of his claims. Fifelfoo (talk) 22:07, 23 September 2012 (UTC)
- Mr. 98 isn't asking for book reviews. If the critques of Diamond's work is so widespread among "real" historians as you note, it shouldn't be hard to find one of those critques and cite it here for others to find. Historians aren't bashful about tearing down the work of their intellectual competitors, so if people who matter are critical of Diamond's work, there should be at least one or two you could recommend us to read for ourselves... --Jayron32 05:15, 24 September 2012 (UTC)
- I read the consensus as being that there is no consensus about whether work such as Diamond's is work at all, (Joel Mokyr, "Eurocentricity Triumphant" The American Historical Review, Vol. 104, No. 4 (Oct., 1999), pp. 1241-1246; Gale Stokes "The Fates of Human Societies: A Review of Recent Macrohistories" The American Historical Review, Vol. 106, No. 2 (Apr., 2001), pp. 508-525). And not in a hostile way. And I'd suggest that that is very much "the consensus is out amongst scholars." George Raudzens (ed) 2001 Technology, Disease, and Colonial Conquests, Sixteenth to Eighteenth Centuries Brill introduces Diamond as one of the great synthesisers, and one of the great simplifiers, and gives the traditional historian's appeal for complexity. I get the feeling from reading about that there's a distinct conflict in long duration world history about theoretical and methodological bases; and that Diamond's own geographical determinism has ended up on the wrong side of whatever shakedown has happened, and that it seems to me that Wallerstein ended up on the right side. Fifelfoo (talk) 05:36, 24 September 2012 (UTC)
- Mr. 98 isn't asking for book reviews. If the critques of Diamond's work is so widespread among "real" historians as you note, it shouldn't be hard to find one of those critques and cite it here for others to find. Historians aren't bashful about tearing down the work of their intellectual competitors, so if people who matter are critical of Diamond's work, there should be at least one or two you could recommend us to read for ourselves... --Jayron32 05:15, 24 September 2012 (UTC)
- I really don't know how to supply a relevant answer regarding verifying the truth of a controversial large scale synthetic history's normative judgements regarding an evidentiary dataset that is the interpretation of physical remains rather than the interpretation of literary texts. It is outside of my evidentiary experience, and Diamond makes unique claims at the edge of what I perceive to be the boundary of potentially valid claims. Apart from buttressing "Just so" stories about European imperialism (as in Guns Germs and Steel), I'm not sure what his publications are actually useful for other than to drive back into the research programmes of the people doing actual interpretive work with physical remains. Diamond's questions are in themselves controversial, due to the difficulty in demonstrating them adequately; and, I'd suggest his judgements are only really respected for their resonance with the feelings already held by their readers rather than for the explanatory power of his argument which is difficult to take because of Diamond's textual distance from the analysis of primary source material. Given the controversy, just reading book reviews of Diamond wouldn't really help you to be able to make judgements regarding the validity of his claims. Fifelfoo (talk) 22:07, 23 September 2012 (UTC)
- I'm not sure "you should read a bunch of unspecified books before considering this question" is really a very useful reference desk answer. At least, if I went to a library, and asked a question, and they responded by saying, "dude, you really ought to survey an entire literature of experts before trying to think about this question," I wouldn't be very impressed. --Mr.98 (talk) 18:15, 23 September 2012 (UTC)
Transgender Animals
[edit]Have there been any documented cases of non-human animals being transgender? Also, it is possible to determine if a non-human animal is transgender or not? Thank you. Futurist110 (talk) 20:13, 22 September 2012 (UTC)
- See Sequential hermaphroditism. Well, maybe not quite what you're looking for. --Wrongfilter (talk) 20:40, 22 September 2012 (UTC)
- There's also an animal equivalent to cross-dressing. There's a cephalopod where small males masquerade as females, so they can get past the dominant males and mate with the females. StuRat (talk) 20:45, 22 September 2012 (UTC)
- That happens with a lot of fish too, although I don't have a source. μηδείς (talk) 04:49, 23 September 2012 (UTC)
- I've heard of that. I wonder if this is due to fish and other animals changing a change in their mind causing them to want to be of the opposite gender or if it is something else? Futurist110 (talk) 01:04, 24 September 2012 (UTC)
- Dr Tatiana's Sex Advice to All Creation (which may not exactly be the most reliable of sources) contains the anecdote of an apparently homosexual penguin couple pretending to mate and after that pretending to hatch an egg (by sitting on a roughly egg-sized stone, as far as I remember) - does that count? (not the penguins being apparently homosexual, but the pretending to have an egg) -- Ferkelparade π 22:22, 23 September 2012 (UTC)
- I guess that could count, if the penguin(s) pretended to be a female. Futurist110 (talk) 01:04, 24 September 2012 (UTC)
- As a practical matter how does that differ from buying a pet rock? ←Baseball Bugs What's up, Doc? carrots→ 03:59, 24 September 2012 (UTC)
- Um...you're not pretending to give birth to it? Futurist110 (talk) 00:57, 25 September 2012 (UTC)
- Don't bet the family jewels on it. If someone would spend cash money on an ordinary rock (note that the penguins get their own pet rocks for free), there's no telling what that someone might do otherwise. ←Baseball Bugs What's up, Doc? carrots→ 01:15, 25 September 2012 (UTC)
- Um...you're not pretending to give birth to it? Futurist110 (talk) 00:57, 25 September 2012 (UTC)
- As a practical matter how does that differ from buying a pet rock? ←Baseball Bugs What's up, Doc? carrots→ 03:59, 24 September 2012 (UTC)
- I guess that could count, if the penguin(s) pretended to be a female. Futurist110 (talk) 01:04, 24 September 2012 (UTC)
- This is an anecdote, but what the hell. We raised a backyard flock of chickens when I was a kid. After an attack by neighborhood dogs left us with one dead rooster (and a bunch of hens), the hen at the top of the pecking order changed genders. Her comb and wattle increased in size noticeably, causing her to resemble a rooster physically -- I have to assume this is triggered by some kind of hormonal change, but I have no idea what's at work there. She began to crow (somewhat feebly), she "led" the flock around the yard as the rooster previously had, and even attempted to mate with the other hens on a few occasions -- at least, she did the mating dance and occasionally mounted one that moved too slow, though obviously nothing happened as a consequence. We read up about this at the time, as I recall, and discovered that this phenomenon is fairly well-known in chicken flocks, but I don't now recall what books we consulted. I couldn't tell you whether this is breed-specific, or really anything else about it other than I watched it happen. It may or may not count for your purposes, but to my mind, it's an example of transgender behavior in the animal kingdom. Jwrosenzweig (talk) 05:50, 26 September 2012 (UTC) (P.S. For the curious, the hen's behavior subsided after a few months, during which a rooster chick was hatched and grew to adolescence -- I don't recall if she challenged him for supremacy at all or if she just slipped into the shadows. Her appearance returned to something more henlike and the crowing and other behaviors never returned for the rest of her brief chicken life.)
- Fun story! I find others ... [16] (search www.google.com/search?q=hen+"crowing+like+a+rooster"&tbm=vid for many...) Unfortunately, for cultural reasons and against all sense, molecular biologists and farmers never seem to communicate directly, and I'm not finding much about this phenomenon in recent research, but there is one study of the role of estrogen at PMID 15327911 , which found that treatment of female fowls with fadrozole brought about crowing behavior about half the time in a very small sample. I didn't find anything recent in a quick poke at references for estrogens in social behavior [17] but more effort might pay off, and if you track down the dead trees for those 60s references you might find something interesting. Wnt (talk) 17:17, 26 September 2012 (UTC)
- _Evolution's Rainbow: Diversity, Gender, and Sexuality in Nature and People_ by evolutionary biologist Joan Roughgarden discusses this topic, including the hows and whys of non-binary gender in animals. 173.49.178.5 (talk) 22:59, 26 September 2012 (UTC)