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by jmprspret 1003 days ago
We don't evolve anymore. Natural selection doesn't happen anymore.

Only way for that to happen would be interplanetary travel (particles and radiation in space affecting DNA for one, space colonies slowly changing over many generations to suit other planet's conditions more likely).
8 comments
0xDEAFBEAD 1003 days ago
In our resource-abundant modern world, you should expect genes that cause people to want kids to do very well. Fertility is low in most developed countries, but that masks particular sub-populations that are growing at a rapid rate. See this article for instance: https://medium.com/migration-issues/how-long-until-were-all-...

Similarly, expect future generations to be full of people who just can't stand wearing a condom during sex.

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leoedin 1003 days ago
Anecdotally, it was my more risk taking and carefree friends that had kids first. I can see why - with just a little effort it's very easy not to have kids in the modern world, and the cost-benefit analysis for children is pretty bad.

What that means for the future of humanity, I don't know.

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0xDEAFBEAD 1003 days ago
It's not necessarily that simple though. Maybe if you have an unplanned child early, you realize that thing about the cost-benefit analysis being bad, stop having kids, and reproduce at below replacement.

Here is one paper I found on correlates of reproductive success in the US, from 2005 though: https://d1wqtxts1xzle7.cloudfront.net/48563240/Sex_Status_an...

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bowsamic 1003 days ago
The only thing that makes human selection unnatural is that we like to define ourselves as above nature
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kergonath 1003 days ago
> We don't evolve anymore. Natural selection doesn't happen anymore.

Of course we do. Why would we not? Evolution is just a fact of life. For it to stop happening, we’d need all humans to have strictly the same number of children who live long enough to have children themselves. As soon as you have something affecting fertility rates, you have selection pressure.

> particles and radiation in space affecting DNA for one

What makes you think this does not happen on Earth? Radiation is everywhere. So is chemistry: there are more ways to alter DNA. On top of that, DNA has intrinsic mechanisms for mutation, in the form of transcription errors. Mutations happen all the time.

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AnimalMuppet 1003 days ago
Well, evolution doesn't happen nearly as much based on disease resistance, now that we have antibiotics. It doesn't happen nearly as much based on ability to survive famine, now that we have modern agriculture. It doesn't happen nearly so much based on ability to survive childbirth, now that we have hospitals. And so on.

That may have been their point.

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CaptArmchair 1003 days ago
Sapiens has only been around for 300k years. Writing and, arguably, civilization is only 5.000 years old. If you subtract 5k from 300k, you still have about 300k left.

If you subtract 300k from 10 million years, you still have about 10 million years left.

The point here is that we are notoriously bad at gauging how big numbers are. We are also bad at intuitively gauging how fast/slow evolution moves.

We are very much still evolving and adapting to our surroundings. It's just that the big changes only become visible way beyond the horizon of a future we are able to conceive.

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shepherdjerred 1003 days ago
Just because we have defined ourselves outside of the term "natural" _doesn't_ mean we aren't evolving like any other species does.
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m463 1003 days ago
> We don't evolve anymore. Natural selection doesn't happen anymore.

I think we do. IVF, cloning and more. People choose to live in safe or risky places. etc...

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Ancalagon 1003 days ago
Natural selection sure, artificial though, definitely.

Women (on average) have preferences for taller guys (on average), where do you think the average height of people are headed? Artificial selection.

Most reproduction is monogamous in modern society. Artificial selection.

I don't mean to offend anyone with those examples by the way, apologies if I did. I also realize the irony that those examples might be opposing forces for the same phenotype I'm referencing.

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alex_young 1003 days ago
Artificial selection refers to our selective breeding of non-humans. The examples you mentioned are natural selection.
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kergonath 1003 days ago
People have a hard time understanding that humans are just animals and also part of nature.
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brabel 1003 days ago
Exactly. By the way, there's a name for human artificial selection: https://en.wikipedia.org/wiki/Eugenics
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alex_young 1003 days ago
Do you really believe that? Sexual selection is a thing of the past?
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