Thread: Evolving Towards Society

Originally Posted by bradysdreaming

You know, like our bodies learn how to deal with food like mcdonalds and we rely on high calorie intakes without much physical effort. Our bodies now still act like we are tribal and expend much energy everyday, but we do jobs that require little physical effort and we have plentiful supplies of food. If a long time from now our bodies evolve to such a thing, society breaking down would lead to extinction of the human race. Would it not? Correct me if I am wrong, I am not completely familiar with the theory of evolution, my mom is super religious and I was home schooled up until last year...

For anything like that to evolve, there would have to be a significant difference in reproductive success between people who eat at McDonalds and don't get fat, and people who eat at McD. and get fat. In addition, you would have to wait a couple of thousand years before genes linked to this type of metabolism sweep through the population. Hopefully, McDonals won't exist in a couple of decades.

Originally Posted by tommo

The human species can no longer evolve, except through technology.

Pretty much.

Originally Posted by tommo

The only reason species evolve is because there is relatively small numbers of them.

So if one of them is significantly better at something than the other, and it helps them survive better, they will produce more offspring to pass on their traits.

The larger the population, the stronger the selection effects are. Larger population are, in principle, more evolvable.
In small populations, evolution happens mostly due to genetic drift.

Originally Posted by SnakeCharmer

The larger the population, the stronger the selection effects are. Larger population are, in principle, more evolvable.
In small populations, evolution happens mostly due to genetic drift.

What? Can you explain that more?

How could you agree with my previous statement, if you think larger populations are more evolvable?

Originally Posted by tommo

What? Can you explain that more?

How could you agree with my previous statement, if you think larger populations are more evolvable?

I agreed with the assertion that human biological evolution is limited, but I didn't agree on the reasons behind it. Technology limits the magnitude of natural selection we are subject to. Infectious diseases, as pointed out by PhilosopherStoned, are pretty much the main thing influencing our biological evolution and imposing selective pressure, since everyone has approximately the same chance of leaving offspring.

Larger populations being more evolvable (maybe adaptable through natural selection is a better way of saying it) is a standard idea from population genetics. Admittedly, there is some controversy surrounding it lately.
For humans, there's some research showing an accelerated rate of adaptive evolution in the past 40-50,000 years, correlated with population growth. Note that this is a cumulative effect over 50,000 years, so we can't really say with certainty how technological evolution from the last 100 years is influencing our biological evolution.