4 ms·

Unless your species is smart enough to prevent pre-reproduction death and cure infertility.

whatshisface 8y ago
I'm not sure what you mean by that, if you're talking about animals then reproduction death is pretty rare (compared to people), and if you're talking about people then reproduction death and infertility have not been cured. Even if they were that would just reduce two selection pressures, leaving every other pressure in place.
- treerock 8y ago
  pre-reproduction death. And in humans that is not something that necessarily needs a cure :)
anonnyj 8y ago
There's sexual selection to account for too.
mbel 8y ago
Being alive and fertile does not imply that you will reproduce. There are other genetic factors that may lower chances of reproducing, like having any kind of flaw that makes given specimen "unattractive" for other specimens.
marcosdumay 8y ago
No, none of that stops evolution. If an species keeps reproducing, it keeps evolving.
jerf 8y ago
If you are snarkily trying to imply that humans have stopped evolving, the genetic evidence points in the utterly opposite direction. Here's a pop science take on the matter but you can dig "human rapid evolution" into Google and read plenty of takes on the matter from many different papers: https://www.wired.com/2007/12/humans-evolving/ https://www.wired.com/2007/12/humans-evolving/
- simonh 8y ago
  And of course even if you could avoid all selection pressures, the species would continue to evolve to take advantage of that change. We will simply evolve out of the adaptions we developed to cope with the threats we have mitigated technologically, and it seems likely to me those changes could be far more profound.
  - InitialLastName 8y ago
    Right, the lack of selection pressure is in itself a selection pressure, in that those individuals more inclined to devote energy to breeding that might have been devoted to survival will out-reproduce the others.
- fpoling 8y ago
  Rapid changes are expected after a selection bottleneck. There is less genome diversity between native European and native Australians than between apes in one herd.
rjf72 8y ago
Evolution is only guided by survival alone in situations where as survival approaches 100%, so does fertility. In humans this is very much not the case for an immense number of reasons even beyond sexual selection. One of the biggest is simply social decisions. For instance there are ever more people that are fully capable of reproducing are 'responsibly' choosing not to. At the same time other populations, including in developed areas, are recklessly reproducing without much concern for anything at all other than themselves. This means the genetic pool of the future will begin to select against the 'responsible' group. Outside of genetic evolution this also has a major effect on cultural evolution. There are strong correlations between fertility and low income, low education, and high religiosity. 'Responsible fertility' means children from these groups will make up an ever larger percent of all new births. Makes one question the notion of 'responsibility' in this regard. There are also survival factors that are not so in your face as e.g. being eaten alive by a predator or starving to death. For instance obesity is becoming ubiquitous, yet it is strongly connected with a wide array of factors leading to infant death - including neonatal. Having a child means nothing if that child is not ultimately able to, in turn, also able to procreate. Another example of this issue would have been in olden times when royalty would sometimes inbreed to the point of committing genetic suicide. See, for instance, the Habsburgs.
- astazangasta 8y ago
  >This means the genetic pool of the future will begin to select against the 'responsible' group. This idea, called "devolution", is dead wrong. First, it presumes some sort of genetic basis for being "responsible", which is hardly in evidence. Second, it presumes no gene flow between these groups, decidedly false as class mobility is nonzero. Finally and most egregiously it posits some form of group selection, whereas selection acts on individual variants.
  - radford-neal 8y ago
    There's every reason to think that personality traits such as religiosity, and indeed simple desire to have children, are genetically influenced. (Not that it's been proven, but that's where one should bet.) There's no need to assume there's no gene flow between sub-populations. Indeed, the existence of gene flow would be why some genetic variants favouring desire to have children could become dominant. There's also no need to assume group selection - individual selection is obviously quite sufficient. And there's no call for describing this as "devolution". You're maybe confusing the original poster with one of the replies...

I'm not sure what you mean by that, if you're talking about animals then reproduction death is pretty rare (compared to people), and if you're talking about people then reproduction death and infertility have not been cured. Even if they were that would just reduce two selection pressures, leaving every other pressure in place.

treerock 8y ago
pre-reproduction death. And in humans that is not something that necessarily needs a cure :)

anonnyj 8y ago

There's sexual selection to account for too.

mbel 8y ago

Being alive and fertile does not imply that you will reproduce. There are other genetic factors that may lower chances of reproducing, like having any kind of flaw that makes given specimen "unattractive" for other specimens.

marcosdumay 8y ago

No, none of that stops evolution. If an species keeps reproducing, it keeps evolving.

jerf 8y ago

If you are snarkily trying to imply that humans have stopped evolving, the genetic evidence points in the utterly opposite direction. Here's a pop science take on the matter but you can dig "human rapid evolution" into Google and read plenty of takes on the matter from many different papers: https://www.wired.com/2007/12/humans-evolving/ https://www.wired.com/2007/12/humans-evolving/

simonh 8y ago
And of course even if you could avoid all selection pressures, the species would continue to evolve to take advantage of that change. We will simply evolve out of the adaptions we developed to cope with the threats we have mitigated technologically, and it seems likely to me those changes could be far more profound.
- InitialLastName 8y ago
  Right, the lack of selection pressure is in itself a selection pressure, in that those individuals more inclined to devote energy to breeding that might have been devoted to survival will out-reproduce the others.
fpoling 8y ago
Rapid changes are expected after a selection bottleneck. There is less genome diversity between native European and native Australians than between apes in one herd.

rjf72 8y ago

Evolution is only guided by survival alone in situations where as survival approaches 100%, so does fertility. In humans this is very much not the case for an immense number of reasons even beyond sexual selection. One of the biggest is simply social decisions. For instance there are ever more people that are fully capable of reproducing are 'responsibly' choosing not to. At the same time other populations, including in developed areas, are recklessly reproducing without much concern for anything at all other than themselves. This means the genetic pool of the future will begin to select against the 'responsible' group. Outside of genetic evolution this also has a major effect on cultural evolution. There are strong correlations between fertility and low income, low education, and high religiosity. 'Responsible fertility' means children from these groups will make up an ever larger percent of all new births. Makes one question the notion of 'responsibility' in this regard. There are also survival factors that are not so in your face as e.g. being eaten alive by a predator or starving to death. For instance obesity is becoming ubiquitous, yet it is strongly connected with a wide array of factors leading to infant death - including neonatal. Having a child means nothing if that child is not ultimately able to, in turn, also able to procreate. Another example of this issue would have been in olden times when royalty would sometimes inbreed to the point of committing genetic suicide. See, for instance, the Habsburgs.

astazangasta 8y ago
>This means the genetic pool of the future will begin to select against the 'responsible' group. This idea, called "devolution", is dead wrong. First, it presumes some sort of genetic basis for being "responsible", which is hardly in evidence. Second, it presumes no gene flow between these groups, decidedly false as class mobility is nonzero. Finally and most egregiously it posits some form of group selection, whereas selection acts on individual variants.
- radford-neal 8y ago
  There's every reason to think that personality traits such as religiosity, and indeed simple desire to have children, are genetically influenced. (Not that it's been proven, but that's where one should bet.) There's no need to assume there's no gene flow between sub-populations. Indeed, the existence of gene flow would be why some genetic variants favouring desire to have children could become dominant. There's also no need to assume group selection - individual selection is obviously quite sufficient. And there's no call for describing this as "devolution". You're maybe confusing the original poster with one of the replies...