There are two forces at work in evolution. Natural selection (survival of the fittest) and sexual selection (reproduction of the sexiest). Out of the two, natural selection is by far the weaker force.
> Intelligence and other positive characteristics don't seem to get involved in whether they have surviving offspring today the way I imagine it did a few thousand years ago.
You're thinking very narrowly in the "survival of the fittest" mode.
You're ignoring sexual selection entirely.
It doesn't matter how hot, strong, or brilliant you are, if you have zero kids, from an evolutionary perspective ... it's the same as if you were killed and eaten by some wild animal.
And, of course, the quality of your offspring matters as well and is determined by mate choice.
There's plenty of evolutionary pressure around today. Actually, I would say it's far more extreme today than ever before, especially in our urban areas.
I can't stress this enough, but there is simply no goal for evolution. Up until relatively recently, it just so happened that larger brains and other features we consider 'human' have been beneficial. Even if it may not be a big factor now, don't decry it as evolution being 'dead', or even worse, that people are devolving.
If certain genetic traits allow certain people to pass their genes down to more offspring then you have all you need. It's a very simple concept with major consequences.
I don't agree with that 100% (the same as just dying part), solely because of the technology and globalization that we currently live with. Even if you don't have children, by simply starting a business where you employ many people, you're essentially providing a means to life for others. If your business is successful, you will have brought life to others via work for possibly generations(which essentially means others can provide a life for themselves and their families). I know that's a bit of a reach, but it's probably true to a small extent, at least in first world countries. Hundreds of years ago, I completely agree with you.
We live in a world where your work can potentially impact billions of people. Sure, you may not reproduce, but you may have enabled many others to do so.
As the article discusses, the major characteristics of human populations in the recent past centre around demographic changes i.e. small populations where drift dominates, giving way to massive population expansion, where mutation and drift likely play a much more powerful role than selection does (for nearly neutral variation, which is the vast majority of variation).
This could potentially change if the human population ceases its expansion, stabilizing at a greatly increased level for a long period and with high levels of gene flow. In this case, selection could have more of an impact on nearly neutral variation than it previously has.
I.e. smarter individuals have less (or no) kids.
If "having what it takes to climb the corporate ladder" is what gives your offspring a better chance of survival, then that is what is being selected for.
I don't think it's a stretch to say that, even in the least developed areas of the world, this is no longer the general case.
Humans are no longer subject to natural selection, since nearly everyone survives to breed.
Selection is always active.
First, there is sexual selection, not just natural selection, and there is no reason to assume that is not important today.
Second, as the article says, there is more genetic variety than before - we accumulated a lot of variation in recent millenia. That's the necessary foundation for selection.
Finally, a quick look around shows that some people have more children than others. You mention "Intelligence and other positive characteristics", but the fact is, it isn't clear intelligence was ever more important than say brute strength/social skills/etc. in our evolutionary history, so the fact it isn't the main factor now says little. But there definitely are factors that do contribute to having more (thriving) children today, and we are selecting heavily for them, for better or for worse.
The juxtaposition of intelligence vs. social skills is amusing given the Machiavellian Intelligence Hypothesis, which suggests that our general intelligence basically evolved precisely as a means to get ahead in the social games that are relevant for sexual selection.
If you can reason abstractly about what some rival is going to do and examine the "game tree" of potential actions, that is surely an advantage both for sexual selection and, say, debugging or proving theorems.
So while people are saying that evolution is "selecting for less intelligence", this may be a short-term effect in which we are first as a species shifting to stronger reproductive urges at the expense of general intelligence, and only then increasing intelligence in a way which doesn't allow philosophical objections to having children.
But evolution is pretty complicated, and difficult to reason about. Other people have also mentioned the "selfish gene" effect, in which altruistic / kinship behavior can be good for a gene, but suboptimal for an individual. It's possible some weird effect like that is going on also.
Also I am not sure you understand what "mortal coil" means:
You don't think that, say, genetic engineering will change the genome? I'm betting we'll be primarily artificially designed by the end of the century.
I did not know that - I really thought "mortal coil" meant the human body. Now that I know I'm wrong, nevertheless I must point out that qualifying "coil" with the word "mortal" is not only misleading but empty of meaning.
The Wikipedia article says that "mortal coil" = "the bustle and turmoil of this mortal life" but I do not believe that "mortal" fits well as an adjective for "coil" just because it refers to a "mortal life".
It seems like a very tenuous connection. Not one of Shakespeare's best poetic terms by far.
EDIT: Thanks for teaching me something interesting today, hnriot.
I'd like to think it is a poetic reference to our DNA.
To stay on topic, I agree with the parent. I think we have reached a point where our genetic makeup is no longer the primary factor determining our destiny as a species.
One could say that intelligent design now trumps evolution, as it were.
Depends. I can envision a lot of scenarios where infectious disease wreaks havoc on our species. Random mutation might have a significant impact on who would survive such a scenario and I don't think we (as a species) are anywhere near being able to circumvent natural selection of a sufficiently dire infectious disease. jmho
It's not only our own biological evolution that deeply affects us.
> Artificial interference is going to kick in long
> before that
This classification of variations into "rare variations" and "common variation" is interesting (and new to me).
Any one knows resources that explain more about this?
Popular science depictions of "mutations" make them sound like "one lucky shot" kind of thing. This model never made sense to me. I figured these variations must be occurring constantly across the population.
It's interesting to me that even the variations which are considered "rare" actually occur at a rate that's around 1 in 100. Hell, even if it was 1 in a 1000, that's still quite a lot.
I need more resources about this topic!
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