I noticed that many black-ish people I've met have bigger lips than the white-ish people I've met. However, not all black-ish people have big lips.  Is there any explanations in terms of natural selection, geographic localisation, common ancestors, or something else that could explain why a subset of dark skin people have bigger lips on average than pale skin people?  Edit: This question is different from the other one because the answer talks about the nose and its function (air temperature) linked to the environmental factors. I don't see how this applies to lips.
123602
I am not even remotely an expert in this field; I just got curious, so help me.   First of all, let us remove all human sentimental attributes from this question (such as connotations of  or emotional reactions thereof) and ask it from a purely scientific point of view. The typical facial feature of a West/Central African person (the so-called ) exhibits a wide nose, a lack of nasal bridge projection (similar to many Asian noses) and a prognathous skull shape that resembles more closely to our ancestor Homo Heidelbergensis than many other indigenous phenotypes from other parts of the world do.  I agree that this claim sounds anecdotal, and is certainly not true of all Africans (for example, Ethiopians), but one cannot dismiss it simply on grounds of ethical policing. I cannot help but notice that many of my African friends remind me of our shared ancestry (with no disrespect meant whatsoever), as is clear from the photographs below, one of a supposed Homo Heidelbergensis and one of a random African Homo Sapiens of today.     My question is the following. What is the reason behind this seeming resemblance? Is this appearance an illusion and possibly a construct of a prejudiced mind, or does this have a valid scientific answer? For example, are most Africans closer to our ancestors than the rest of humanity is? How does evolution answer this question?  Thank you for your help.
72012
From some basic googling, I found that nobody has ever proven that people are born gay and that environment plays a great part in homosexuality.  I wish to know if there is a genetic component to homosexual behaviour. If so, how significant is that component (in some measure such as percentage contribution to the behaviour). What are other factors that play a role in homosexuality i.e. what constitutes environmental factors?
47878
What words do we use to describe an unmatched couple, for instance, the female is much more attractive than the male, or the other way around?   If we found that a girl is out of the league of her boyfriend (8 vs 5), or the other way around, how would we describe such a couple?
71115
I know a black body is an object that absorbs all wavelengths of light, and also emits all wavelength of light too back out, but if it emits all wavelengths of light, why does it appear black, as all wavelengths combined appear white?  Also, with stars, I know they are assumed to be black bodies, but do they appear a certain colour just because they emit more of one wavelength than any other.   Edit: Looking at the link in the comments, I kind of understand why black bodies don't have to be black, but what does,it mean for something to be the colour black, like a black radiator? is black paint a black body?
53348
To be clear, I'm not doubting that homo sapiens and homo neanderthalensis did interbreed: of that much I'm convinced.   Within the past few years I've seen an upcropping of pop-sci articles discussing the interbreeding between pre-historic species of humans. In everything that I see in these articles, as well as in scientific literature (my college Bio textbook, among others), I see these different humans being referred to as separate species.   This conflicts with my understanding of a species. Given the following definition, wouldn't homo sapiens and homo neanderthalensis be the same species?     A species is often defined as the largest group of organisms where   two hybrids are capable of reproducing fertile offspring, typically   using sexual reproduction.      Is this definition incorrect?  Are the publications using "species" colloquially, as opposed to scientifically?  Is "species" still a poorly defined concept? (see )   Thanks!
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It is often cited that humans share 99% (or 98%) of their DNA with chimpanzees.  On the other hand it is stated that siblings share only half of their genes.  What (if any) is the difference between DNA and genes; or, how can the above two claims be reconciled? (I am assuming of course that chimps and humans are more different from each other than two siblings are from each other.)   (I am asking this question as a layperson, who had a little biology in school but not much more.)  June 2015 Addendum: Here is a nice  just released by MinuteEarth; I do not know how accurate this video is, but as a layperson I found it insightful.
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As an example, let's say someone with 1/16 of African American heritage applies for a minority scholarship and claims themselves as African American. Would they be rejected, all other factors being equal? If so, do universities generally publish a guideline of what constitutes a particular race in the context of scholarship applications or college admissions?  Note that this question is of practical value as there are presumably millions of people of mixed heritage living in the US at the moment.
32553
After my online research on the subject, I learnt that, biologically speaking, many scientists believe that there is no such thing as a race. Homo sapiens as a species is only 200,000 years old, which has not allowed for any significant genetic diversification yet, and our DNA is 99.99% similar. I've read statements that there can be more genetic variation inside a racial group than between different racial groups, meaning that, for example, two individuals from the same "race" can have less in common with each other than with an individual from another "race".  :     Scientists consider biological essentialism obsolete, and generally discourage racial explanations for collective differentiation in both physical and behavioral traits     Q1: If Homo sapiens has no races (according to biologists), why are we so different morphologically? (hair/eyes/skin colour and even athletic performance seem to differ between human populations)  Q2: Is it common for other species too, when genetically close populations have very different morphological traits? Are there any other mammal or animal species that exhibit biological diversity comparable to human diversity, and how do taxonomists treat these species? (excluding intentionally bred domestic species to keep the comparison fair)    The question has been paraphrased to emphasize that it is the biological debate that is in question, not the sociopolitical. I.e., why is there no consensus in evidence and opinions of scientists?
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Why do people in different areas speak differently? Where do accents come from, how do they change and/or survive over time and why do we have them?   Reading recommendations on this topic would be welcome.
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I have close to two hundred images where the subject looks like he just walked out of a sauna. It was 36 degrees with humidex, but he was not that red.   For comparison, attaching another picture, same camera, same lens, auto white balance, next day.       So, two questions, 1) how did that happen?, and 2) how do I fix it? I can bring down the red, but then I have to manually bring back the lip color in 200 pictures.   And next time when I deal with an older guy at 36 degrees C I will be shooting indoors.   *Edit: The camera is Olympus EPM 2. I am now guessing that he may have been THAT red, but my eyes tricked me. The last picture is from the beginning of the shoot before he got very hot and had two glasses of wine AND the background worked better for his skin and clothes. I do not have colour management setup, but I will get on it.
85208
Apparently, there is an advantage to having 6 legs in the insect world. What is that advantage, if anything? Why would such an advantage exist for insects, but not for other, larger land animals?  What do those middle legs do that the front and hind legs cannot, if anything? Are they really essential, or do they just generate more muscle power?
75993
I have been wondering how to achieve a great portrait effect I have been seeing a little bit more lately.  The portraits are usually washed out, but blacks are still deep (not dull), and there seems to be some kind of a blue tint.  Here are examples:      How would I achieve something like this from a well lit, standard portrait shot?
13581
When we list pairs of words, certain orders seem much more common and natural than others.  A few examples:   Fish and chips instead of chips and fish Ladies and gentlemen instead of gentlemen and ladies (likewise, men and women instead of women and men) I'm sure we've all (?) had those disagreements about whether it's Rob and Salma or Salma and Rob (or whatever)   In most of these cases though, I struggle to rationalise why one order sounds more 'right' than another.  Is it purely a historical accident that one order is more common than another? Or are there subtle linguistic rules that are responsible?
11809
If a trait would be advantageous to an organism then why hasn't it evolved yet?  Conversely, if a trait is not advantageous or mildly disadvantageous, why does it exist?  In other words why does evolution not make the organism more "perfect"?    This is a general question that would be applicable for any kind of trait. Please keep the answers precise and scientific.   Read this meta post for more information:
103611
How do you set your camera in settings to TAKE photos that come out with the skin looking more tanned and bronzed than in real-life? Instead of changing the photo afterwards. Preferably Canon, but any other camera is fine.   Something like this:
97953
The dinosaurs, mammoths, giant plants etc are known to be bigger than modern animals. I wonder why they had been lived and why they are not living now? I really don't know much but is it something about oxygen balance or something similar?
95093
I'm a newbie at stats, so if I make any mistaken assumptions here please tell me.  There's a population N of people. (For example N can be 1,000,000.) Some of the people are redheads. I take a sample n of people (say 10,) and find that j of them are redheads.  What can I say about the general proportion of redheads in the population? I mean, my best approximation is probably j/n, but what would be the standard deviation of that approximation?  By the way, what is the accepted term for this?