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What evolutionary changes might be happening now?


Given that it would be next to impossible to actually predict what will happen to humans through evolutionary processes, are there any clues which might suggest current changes?

I can think of a few.

1. Brain size. With the emphasis on education and caring for others, and poor people tending to have larger families, would it be reasonable to suggest we are breeding intelligence out of humanity?

2. Autism spectrum, in some cases confers some advantage in ability to focus and be obsessive about detail and practical skills, which arguably has prevented autism to breed out. With current education policies, people on the autism spectrum might have more opportunities to procreate.

3. Female size: Are women getting bigger? It has been suggested that female size in primates is related to female equality, and specifically monogamy. Where there is competition among males they tend to be bigger. With male humans no longer needing to fight for a mate, and there being no particular reason for women to be smaller, are women reaching a similar size to men? Look at Maria Sharapova and Serena Williams, both very much women but in musculature and size the equal to most men.



Opened my window to listen to the news But all I heard was the establishment blues!

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no, no ,and no





"A wise man proportions his belief to the evidence." David Hume

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...I'm growing a pair of wings...

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From an anthropological viewpoint;

look at the physical stressors:

Pollution, diet, sexual interaction choice and so many more (it's early morning w/o coffee).

Consider which things affect procreation and passing on of adaptive and non-adaptive genes.

Humans will adapt (or extinct) from outside pressures from the environment, and the result will be our evolution.

Yes, I think machines are dumbing us down, en masse, but I don't think this is genetically inheritable but sociological adaptability. Flexible.

Wishing Steven Hawking could pass on his intelligence genes; sexual selection factors in as well.
Gotta have sex to pass on your genes. If they are +adaptive=survival, if -adaptive=extinction.
Lucky we have such a large and diverse gene pool.

Impossible is illogical.
Lack of evidence is not proof.
 +  = 

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I believe that more and more people are being born without wisdom teeth. Not exciting, but it's something, lol


Trying is the first step towards failure Homer Simpson

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I was born with one wisdom tooth.

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It's very difficult to say what kind of selection pressures apply to humans because human society is so complicated. For example it is true that people who pursue higher education and prestigious careers tend to have fewer children than poor poeple working blue-collar jobs. On average, smarter people are more likely to be in the former category so it might be tempting to speculate that intelligence is being selected against. That could be true but on the other hand there might be myriad other instances where intelligence is selected for, like what kind of choices people make regarding their health care for instance. So it's feasible but highly uncertain. I don't see autism being selected for because, while it may be true that autistic individuals are better able to function in society today, having deficits in social interaction still confers a disadvantage compared to the "average" person as far as reproduction is concerned. As to the size differences between the sexes disappearing, it is true that generally sexual dimorphism is a result of violent competition among males for reproductive access but it's not clear that merely removing this aspect of behavior will remove the selection. While the dimorphism in our species may have arisen due to violent male competition some time in the past there is now also a sexual selection element to it. Males prefer shorter women and females prefer taller men. Given this fact it makes sense for the genes of a woman to make her find taller men more attractive because if she has a son he will be taller and thus will have more success with the ladies, passing on more copies of those genes to the next generation. Thus, even in the absence of male competition there is a kind of perpetuated cycle thing going on (see the "sexy son hypothesis"). I would also point out that elite athletes are not always a good representation of the general population.

I should also say that living in a wealthy nation in the developed world may give one a misleading picture of the environmental pressures our species faces. The fact of the matter is that the majority of humans don't have access to quality health care, good education or white-collar jobs. In much of the world humans still struggle with disease, starvation and violence and so the selection pressures they face might not be as different from those of our ansestors as one might imagine. Since human societies are no longer isolated and there is a fair amount of interbreeding the results of those pressures can propagate across the globe. It bears keeping in mind that we in the delveoped world are the exception rather than the rule.

But having gotten the boring spoil-sport stuff out of the way let's suppose that the conditions of wealthy nations become ubiquitous worldwide and speculate what pressures might drive the evolution of our species. I think the biggest obstacle for natural selection is the fact that with the advent of birth control and abortion sex has become uncoupled from reproduction. So perhaps some changes we might expect would be insensitivity to birth control, rise in latex allergies, more susceptibility to aclohol, rise in impulsivity -- all of which, I think, increase the chances of pregnancy. One might even posit that religiosity might be selected for if it is heritable as many religions discourage abortion (and sometimes even birth control) and encourage procreation.

There has also been growth in veterianism which I think will only continue as eating meat will become more and more ethically unacceptable in society. If vegetarianism and veganism become prevalent enough perhaps we might see the loss of some aspects of our digestive system which has historically been tailored for digesting meat. Another thing that will probably happen is the disappearance of "races" as our society becomes more and more global and different populations interbreed. There might also be some adaptations due to the rising temperatures and climate change. One can speculate endlessly.

I think the problem is that human society is fluid and flexible on time scales which are much shorter than what is needed for evolution to occur. So if say latex allergies becomes more prevalent because people with them are less likely to wear condoms we will just invent another material. Or suppose that it's true that intelligence is selected against due to educated people having fewer children. Once the average intelligence reaches a certain point - boom, Trump becomes president, burns the civilization to the ground and suddenly intelligence is again advantageous as you need to rebuild society. Or if killing animals for food becomes unacceptable we might deal with it by inventing cultured meat grown in a lab rather than going vegetarian. So while there might be many selection pressures that exist today the question is can they exist for long enough?

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Non of the above. The human population is too large and interconnected for natural selection to do anything. Added to this is the fact of medical miracles that keep people alive where they would have otherwise died.

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I believe that more and more people are being born without wisdom teeth. There are people born who never grow wisdom teeth, you mean, right? I'm not trying to be pedantic, even if I am such, as I just want clarification.

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The human population is too large and interconnected for natural selection to do anything.
I don't see how it is possible to turn off natural selection.
Whenever there is a trait that makes procreation more successful (eg enough money to pay for expensive medical treatments) those traits will be selected for.



Opened my window to listen to the news But all I heard was the establishment blues!

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