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October 25

Chimpanzees talking

Why can't chimpanzees reproduce the sounds of human languages? Is it because they aren't smart enough, or are they just not physically capable of it, due to the structure of their throats, etc? FreeKnowledgeCreator (talk) 23:41, 25 October 2018 (UTC)[reply]

This article[1] indicates it's not quite either one of your options. ←Baseball Bugs ^{What's up, Doc?} carrots→ 00:29, 26 October 2018 (UTC)[reply]

Why can't humans reproduce the sounds of whale languages? Is it because they aren't smart enough, or are they just not physically capable of it, due to the structure of their throats, etc? --Cookatoo.ergo.ZooM (talk) 16:46, 1 November 2018 (UTC)[reply]

October 26

What snake am I?

Living in Oran, Algeria (coastal, scrub/forest, ~ 300m altitude). My best guess is southern smooth snake, but I'm not really convinced. Thanks, Henry ^Flower 20:21, 26 October 2018 (UTC)[reply]

Or Western_false_smooth_snake. Ruslik_Zero 20:52, 27 October 2018 (UTC)[reply]

It's hard (for me, at least) to tell the difference from this angle; unfortunately I didn't get much of the face. Henry ^Flower 07:50, 28 October 2018 (UTC)[reply]

Perhaps a Montpellier snake, presumably the insignitus sub-species from the location. Mikenorton (talk) 09:11, 28 October 2018 (UTC)[reply]

Thanks -- I'll have a look at that one too. Henry ^Flower 18:08, 1 November 2018 (UTC)[reply]

October 30

Influenza vaccine

Supposedly each year's influenza vaccine consists of three strains which the CDC(?) has decided are the biggest threats for that year. Some years a strain(s) from the previous year is included again. My question is, should there be Wikipedia mentions, perhaps in a list article, for these strains? Here is the list for 2018. Abductive (reasoning) 19:10, 30 October 2018 (UTC)[reply]

They are chosen by WHO, not by CDC. We already have Historical_annual_reformulations_of_the_influenza_vaccine, which is linked from the main article. Ruslik_Zero 20:34, 30 October 2018 (UTC)[reply]

Access request to scientific databases to enable research into the productivity of photosynthesis in low CO2 contexts such as at the last glacial maximum..

I would like to expand and perhaps modify the text at Carbon dioxide in Earth's atmosphere#Effects of increased CO2 on plants and crops so as to incorporate information on the effects of lower levels of CO2 on plants.

Most scientific research, in its natural bent to follow the money, has been conducted in the effects of increased CO2 on crops yet, when I contacted one professor who had worked on a related topic, she said that she had somewhere seen results from projects in the effects of lower levels of CO2.

I think that this is an important area of research as it will help to provide a wider understanding of the context in which our ancestors developed.

Basically the CO2 content in the atmosphere at around the last glacial maximum was around 180 ppm (parts per million).
In the pre-Industrial context it had reached about 280 ppm.
In our industrial times it's reached 400 ppm and much is made of the effects of the various productivities of plants.

I read somewhere that CO2 contents at the end of the Carboniferous period had sunk to around 100 ppm.

I'd appreciate help in gaining access to relevant scientific papers.

My current plan would be to start with a google scholar search such as: photosynthesis "carbon dioxide" ppm (glacial OR "ice age") and see how things progressed from there.

Greg Kaye 20:02, 30 October 2018 (UTC)[reply]

I suspect that the topic of the effect of carbon dioxide levels on the growth, physiology or existence of plants is a notable topic itself, and so could have a separate article. Anyway, once you find a specific item you want, you can ask at the specific page for this sort of thing at Wikipedia:WikiProject Resource Exchange/Resource Request. It would be a good idea to find a text book or review article that covers this to make sure that only considered information is included rather than wild ideas. On the other side of the situation I like the Azolla event, where plants modified the global CO₂ level. Graeme Bartlett (talk) 21:41, 30 October 2018 (UTC)[reply]

Choice of good search terms is often extremely important. I tried low co2 plant biochemistry and found Physiological Significance of Low Atmospheric CO2 for Plant–Climate Interactions on the first page. --Kharon (talk) 03:50, 31 October 2018 (UTC)[reply]

That's very true. I accessed another set of results by finding a notable article and going through the list of other articles that had cited it.[2]. However most of articles I've found so far, by any route, have focused on research into fossilised carbon. I've found a number of those one of which is open access. When I have time I'll go back to look for studies into growth characteristics of contemporary plant stocks when in low carbon contexts. I appreciate that, since the last glacial maximum, carbon synthesising organisations have had many thousands of years to evolve in ways that may have adjusted their suitability to take advantage of higher carbon concentrations. However I'd hope that many and perhaps all test results would be informative. Greg Kaye 10:44, 1 November 2018 (UTC)[reply]

November 1

Why was the Warsaw Radio Mast a half wave tall instead of quarter wave?

What benefit did half wave have that quarter wave didn't? Sagittarian Milky Way (talk) 20:01, 1 November 2018 (UTC)[reply]

You should read Dipole_antenna#Dipole_variations. Ruslik_Zero 20:09, 1 November 2018 (UTC)[reply]

Why wasn't it a quarter wave monopole? Sagittarian Milky Way (talk) 20:15, 1 November 2018 (UTC)[reply]

The feed impedance will be very different. For a quater wave monopole this might be around 37.5 Ohms, but the end of the halfwave monopole has a high impedance. For the 2 MW / 120kV combo this is about 7200 Ohms, which probably fits in much better with the valves in the transmitter used to drive the antenna, and avoids the use of a large transformer making a high current. However I would expect that a the cost of a huge transformer may have been less than building the world's highest structure. Secondly the radiation pattern is doubled along the horizontal, so that the power is effectively doubled. Graeme Bartlett (talk) 08:55, 2 November 2018 (UTC)[reply]

November 2

Can 2 people eat the same food, and 1 gets diarrhea, the other does not?

So I recently found out about the 2 types of diarrheas: the ones caused by viruses (food not cooked enough), and the others with excess water to the bowels (such as too many solutes, such as too much magnesium or vitamin C). So my question is, what are other factors, besides immunology? For immunology, I imagine such a case where 1 got immune from eating the same contaminated or undercooked food. The only other variable I can think of is allergies, I wonder if eating food 1 has allergies to, can cause diarrhea. Thanks. — Preceding unsigned comment added by 67.175.224.138 (talk) 00:09, 2 November 2018 (UTC) 67.175.224.138 (talk) 00:09, 2 November 2018 (UTC).[reply]

Yes - 1 might not. I've traveled to some far-off places with what I consider dodgy hygiene practices. Fast food from a market stall in Jerusalem gave me problems but the locals ate it with impunity. After a few weeks I was able to do so too. I did not become immune to anything. My gut flora adapted. 196.213.35.147 (talk) 06:00, 2 November 2018 (UTC)[reply]

Actually a big percentage of Foodborne illness is caused by bacteria not viruses. Our article says albeit without a source that "one third of cases of food poisoning in developed countries". It also mentions there tends to have been an overestimation of bacterial causes in the past due to a lack of sufficient testing for viruses, and it's of course true that not all foodborne illness results in diarrhea, but definitely a lot of bacterial causes do and I don't think many epidemiologists or medical doctors will ignore bacteria as a cause. The phenomena describe by the other IP is well known, see Traveler's diarrhea for information. It's also sometimes called "Montezuma's revenge" and "Delhi belly". Nil Einne (talk) 07:21, 2 November 2018 (UTC)[reply]

BTW Coeliac disease is an example of a disease which can have diarrhea as a symptom, which can develop in some individuals depending on several factors including genetics. For people with the disease, a Gluten-free diet is the only accepted treatment which will generally improve, but may not eliminate symptoms. However as mentioned in our article, it's not an allergy. Wheat allergy is something else. While there may be others who will benefit from a gluten-free diet, as our article mentions it's also very common as a fad diet and for a lot of people there's little evidence it has any real benefit, for example in reducing diarrhea. Irritable bowel syndrome can also have diarrhea as a symptom and as our article says, the cause of IBS is still not well understood but diet appears to help management for some people. Nil Einne (talk) 07:45, 2 November 2018 (UTC)[reply]

Poisonous snakes and frogs question.

Are poisonous snakes and frogs immune to their own poison. And if so - are they immune to the poison from other snakes/frogs of the same species, but different breeds? Or of different species of snakes/frogs. Note I'm not asking about snake biting frog or frog poisoning snake, but snake on snake vs. frog on frog. The venom that they secrete. Would the same breed or same species be immune to itself. Thanks. 67.175.224.138 (talk) 00:16, 2 November 2018 (UTC).[reply]

Apparently they are at least immune to their own venom.[3] ←Baseball Bugs ^{What's up, Doc?} carrots→ 00:56, 2 November 2018 (UTC)[reply]

Golden poison frog indicates the species members cannot poison each other. ←Baseball Bugs ^{What's up, Doc?} carrots→ 01:01, 2 November 2018 (UTC)[reply]

According to this article,[4] venomous snakes are resistant to snake venom, but not necessarily immune to it. ←Baseball Bugs ^{What's up, Doc?} carrots→ 01:04, 2 November 2018 (UTC)[reply]

This article on snake cannibalism raises some interesting questions. [5] I would imagine the snake being eaten has been bitten by the larger snake thus killing/neutralizing it. 196.213.35.147 (talk) 06:21, 2 November 2018 (UTC)[reply]

Some interesting stuff at kingsnake (so-called due to their penchant for eating other snakes, including poisonous ones). They themselves are not venomous, but they're immune to many venomous snakes suggesting that venom creation and immunity are distinct adaptations. Matt Deres (talk) 12:16, 2 November 2018 (UTC)[reply]

"Sentient" life on land vs in the seas

Given that 70% of the earth is covered by water, one might reasonably expect that sentient life (and thus civilizations) would develop there rather than on the land. I would suggest that there are likely some significant advantages to a water environment over a land-based one. Are there any theories as to why sentient life and civilizations developed on land but not in the seas (as the largest bodies of water)? What is it about the land that gave the edge to sentience developing there? 76.71.159.5 (talk) 02:08, 2 November 2018 (UTC)[reply]

How will the dolphins use tools? Flippers aren't very good at tool use or holding things. And who knows maybe dolphins are sentient, at least a little. If they are sentient then they're raping bastards, still like wild animals. Sagittarian Milky Way (talk) 02:37, 2 November 2018 (UTC)[reply]

Maybe the octopi have the potential for civilization but farming started civilization on land, not sure how that'd work with a carnivorous creature. Sagittarian Milky Way (talk) 02:42, 2 November 2018 (UTC)[reply]

Let me use the word "evolve" instead of "develop." Evolution allows for the development of tool manipulating appendages. The octopus can use tools. Why could a sentient aquatic creature not farm in the ocean? 76.71.159.5 (talk) 02:47, 2 November 2018 (UTC)[reply]

What would they farm? ←Baseball Bugs ^{What's up, Doc?} carrots→ 03:10, 2 November 2018 (UTC)[reply]

Being non-fully carnivorous and missing some abilities actually helps IQ, our closest living relatives can easily convert live prey into skeletons or live off leaves both without tools, and are much stronger and harder to knock out than men, prehumans lost the ability to do that and compensated by inventing tools like weapons, grinding shit with rocks and cooking. Thus the ones that did that progressed to hydrogen bombs and interstellar travel while the ones that didn't are still eating without farming and have the smarts of a 3 year old. A flying animal might also have less incentive to human level intelligence. For one, birds have very low fuel economy and IQ costs calories. Sagittarian Milky Way (talk) 03:20, 2 November 2018 (UTC)[reply]

In effect, animals are what humans once were: hunters and gatherers. ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:08, 2 November 2018 (UTC)[reply]

Question about the derivation of dy/dx?

Derivatives show us how fast something is changing at any point. For example; the gradient of the graph of y = x² at any point is twice the value of x thereat. The process of finding the derivation of a gradient / slope of a function y=f(x) or y = x² is as follow.

Pick any two points A and B close to each other on the curve of y =x². The coordinates of A on the curve are (x, y) or (x, x²). Add Δx at A as usual. When x increases by Δx, then y increases by Δy. The x changes from x to (x +Δx) while y changes from y to (y + Δy) or f(x) to (x+Δx)². Thus the x and y coordinates of B on the curve are (x + Δx, y + Δy) or ([x+Δx, (x+Δx)²]. Now the instantaneous rate of change is given by

Δy/ Δx = [(x + Δx)² – x²] / [x + Δx - x]

Δy/ Δx = [x² + Δx²+2xΔx − x2] / Δx

Δy/ Δx = [2x + Δx] / 1

Reduce Δx close to zero by taking limit (Δx to dx and Δy to dy)

dy /dx = 2x + dx

dy /dx = 2x------Eq1 OR

dy = 2x.dx --Eq2

ABC is an infinitesimal triangle made by dx, dy, and hypotenuse or slope of tangent where point A and C are always on the curve. Length of AB = Base = dx, Length of BC = Perpendicular= dy and Length of Hypotenuse = AC. Angle CAB or BAC is the slope of a tangent

According to the aforementioned Eq1 or Eq2-

• dy/dx is directly proportional to x or angle CAB is directly proportional to x.

• dx is indirectly proportional to x OR x is inversely proportional to dx

• dy is directly proportional to x.dx or dx

The length of dx > dy when Angle CAB < 45 degrees

The length of dx = dy when Angle CAB = 45 degrees

The length of dx < dy when Angle CAB > 45 degrees

The proportionality of both the angle CAB and dy with x are in contradiction with the proportionality of x and dx in the triangle ABC after probing the equation of dy/dx = 2x beyond its derivation on a graph of y = x2. When x increases; dx decreases, dy increases, and angle CAB increases. This means AC also increases and ultimately SECANT when x increases. Our goal is to bring dx, dy and AC to zero (not away from zero either positively or negatively - Point C has to be on the curve) or secant to tangent by reducing them close to zero but here dx heads toward zero but dy and AC increases when x increases on axis mathematically.

Although the difference in the length of dx and dy can be noticeable clearly on the graph if we examine the triangle ABC at two different points for a gradient (dy/dx), say when an angle BAC = 0.1 degrees and 89.9 degrees on the curve but UNIT CIRCLE is the best example for observing the change in an angle CAB (say 0.1 and 89.9 degrees) of a triangle ABC for dy and dx and the comparison of their lengths.

RISE = dy = 2x and RUN = dx = 1 (always constant) in a GRADIENT of 1 in 2x which we obtained from the Eq1 of dy/dx=2x /1 at any point on the curve when there is no difference between secant and tangent – No idea how do we get dy/dx = 2x.dx but above said contradiction may be due to the introduction of another curve of y =(x+dx)² at a point where we seize x or y=x² deliberately and introduce delta x OR when function y = f(x) changed to y=f(x+Δx)². The value of x has reached to its maximum value instead of unlimited when a curve y=x² doesn’t continue anymore at a point where we introduce delta x or dx as y=x² and y =(x+dx)² are two different types of curve (two diffrent functions).

Further, integration is the reverse process of differentiation. Although delta x or dx is ignored during the process of derivation of dy/dx becaue of their small values but we can’t ignore them in the process of integration which makes a lot of difference in summation. They can’t be disappeared forever and should resurface during the process of integration or summation.

Similarly, dy is the small vertical change in y, therefore, we take the sum of all the small vertical lengths [dy(s)] not the whole slice or y-coordinate(s) from zero to its value on the curve when we integrate both sides of the equation of dy = 2xdx but it turns into function of x² or area under the graph – no idea how but summation of vertical lengths on a graph gives vertical length only not curve?

Is the derivation of the natural relationship of a gradient of 1 in 2x at any point with y=x² or dy/dx=2x still unbeknownst to illuminates?Eclectic Eccentric Kamikaze (talk) 06:08, 2 November 2018 (UTC)eek[reply]

I'm not certain that I've understood your problem with the standard derivation, but your erroneous conclusion that "dx is indirectly proportional to x OR x is inversely proportional to dx" seems to be where your confusion starts. Also, it's the tangent of the angle that is proportional to x. For integration, it's the vertical slices of width delta x that are summed to give a total area. See our article Trapezoidal rule. Dbfirs 07:52, 2 November 2018 (UTC)[reply]

Southern skies

The "Daily Telegraph" of 20 October reports the results of an evaluation by the National Physical Laboratory of the blueness of the sky around the world. The top three locations – Rio de Janeiro, Bay of Islands (New Zealand) and Ayers Rock (Australia) are all in the southern hemisphere. Cornwall came bottom. I can vouch for this – the sky in Perth, Western Australia is a deeper blue than it is here – but why the geographical bias? Is it something to do with the amount of moisture in the atmosphere? — Preceding unsigned comment added by 2A00:23C1:CD83:1F01:B1DD:854C:CF46:CA19 (talk) 09:58, 2 November 2018 (UTC)[reply]

I found National Physics Laboratory - Blue Sky Science which links to Expedia’s Best Blue Sky: Experiments and Results but am none the wiser. Alansplodge (talk) 11:29, 2 November 2018 (UTC)[reply]

The Wikipedia article about the color of the sky is at Diffuse sky radiation and the answer is that the color of the sky is a complex melange of factors, including specific kinds and amounts of gases and particulate matter in the air, air pressure, angle at which the sunlight strikes the sky on that particular day at that particular latitude, etc. etc. It isn't just one simple thing. --Jayron 32 11:42, 2 November 2018 (UTC)[reply]

Speculation is that it is due to nitrogen oxides in the air, these add a brown colour. Smoke and dust would also degrade sky colour. All these substances are less in the air in the Southern Hemisphere due to less pollution and unvegetated deserts. It may also be affected by clouds, and so actually fluctuate wildly from time to time. (on p 28) Graeme Bartlett (talk) 11:45, 2 November 2018 (UTC)[reply]

Hypothesis: there is less land in the southern hemisphere, and so likely less dust and pollution produced there. Winds tend to flow west to east, so southern hemisphere dust and pollutants will mostly stay in the south, while those from the north will mostly stay in the north. Therefore the air the south will be clearer. A quick Google search for "global air pollution map" does seem to support my theory that there will be more pollution produced in the northern hemisphere. Iapetus (talk) 12:09, 2 November 2018 (UTC)[reply]

Siblings procreating

In the TV show Game of Thrones, two characters, Cersei and Jaimie, are twins involved in an incestuous relationship. They have also produced three children (the oldest was a sadist and psychopath). My question is: what are the genetic implications of twins having children together and is there more risk (genetically) for the children having developmental problems when compared to non-twin siblings procreating? 142.46.150.122 (talk) 12:53, 2 November 2018 (UTC)[reply]