When sexual selection can lead to a decline in the capacity for survival
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Re: When sexual selection can lead to a decline in the capacity for survival
#2> But the evolutionary mechanism behind this novelty is not adaptation by natural selection, in which only those who survive pass on their genes, allowing the species to become better adapted to its environment over time. Rather, it is sexual selection by mate choice, in which individuals pass on their genes only if they’re chosen as mates.
TFA has a weird definition for natural selection.
Evolution has no preferences and sexual selection is natural selection.
Re: When sexual selection can lead to a decline in the capacity for survival
#3The puzzlement over the apparent reproductive disadvantages of wing-singing is simply a reflection of a misunderstanding of how evolution works. Evolution does not select for the reproductive fitness of species, it selects for the reproductive fitness of genes. And it does not select for the absolute fitness of genes, but rather for their fitness relative to competing alleles with respect to a particular environment. The genes for wing-singing are better at reproducing themselves in an environment where manakins already exist than the genes for alternative strategies for finding mates. That this might hurt the reproductive fitness of the other genes that go into making club-wing manakins matters not at all to the wing-singing genes. Genes don't think these things through. Genes don't think at all. Some genes build things that think, and some of those things that think end up being puzzled by the behavior of genes, including the very genes that built them.
Re: When sexual selection can lead to a decline in the capacity for survival
#4> But the evolutionary mechanism behind this novelty is not adaptation by natural selection, in which only those who survive pass on their genes, allowing the species to become better adapted to its environment over time. Rather, it is sexual selection by mate choice, in which individuals pass on their genes only if they’re chosen as mates. TFA has a weird definition for natural selection. Evolution has no preference…
Agreed. This is more akin to evolution being stuck in a suboptimal (and perhaps a dead-end) local minima - but it is still natural selection as more pleasing features = survival on an individual scale.
Re: When sexual selection can lead to a decline in the capacity for survival
#5The puzzlement over the apparent reproductive disadvantages of wing-singing is simply a reflection of a misunderstanding of how evolution works. Evolution does not select for the reproductive fitness of species, it selects for the reproductive fitness of genes . And it does not select for the absolute fitness of genes, but rather for their fitness relative to competing alleles with respect to a particular environment…
You're describing this viewpoint: https://en.wikipedia.org/wiki/Gene-centered_view_of_evolutio...
however I don't think it's really an accepted (in terms of evidence) theory that explains all evolution. I think most biologists think that evolution selects at multiple levels (although likely the underlying processes are much more complex than just that).
After all, no real visible phenotype is truly based on a single gene, but rather the dynamic interplay of hundreds of gene products over the course of the organism's development.
Re: When sexual selection can lead to a decline in the capacity for survival
#6> But the evolutionary mechanism behind this novelty is not adaptation by natural selection, in which only those who survive pass on their genes, allowing the species to become better adapted to its environment over time. Rather, it is sexual selection by mate choice, in which individuals pass on their genes only if they’re chosen as mates. TFA has a weird definition for natural selection. Evolution has no preference…
Agreed. This is more akin to evolution being stuck in a suboptimal (and perhaps a dead-end) local minima - but it is still natural selection as more pleasing features = survival on an individual scale.
Small aside: local minimum. Minima is plural (like datum/data).
Re: When sexual selection can lead to a decline in the capacity for survival
#7The puzzlement over the apparent reproductive disadvantages of wing-singing is simply a reflection of a misunderstanding of how evolution works. Evolution does not select for the reproductive fitness of species, it selects for the reproductive fitness of genes . And it does not select for the absolute fitness of genes, but rather for their fitness relative to competing alleles with respect to a particular environment…
You're describing this viewpoint: https://en.wikipedia.org/wiki/Gene-centered_view_of_evolutio... however I don't think it's really an accepted (in terms of evidence) theory that explains all evolution. I think most biologists think that evolution selects at multiple levels (although likely the underlying processes are much more complex than just that). After all, no real visible phenotype is truly based on a single…
> You're describing this viewpoint
Yes.
> evolution selects at multiple levels
That's just another way of saying that evolution selects for reproductive fitness with respect to a particular environment. If a gene is part of an organism, then the other genes in that organism are part of that gene's environment.
The aggregation of genes into organisms is itself an evolutionary adaptation (as is the aggregation of organisms into more complex organisms like eukaryotic cells and multi-cellular creatures). This aggregation provides reproductive fitness by enforcing a certain level of cooperation among the aggregated genes (see https://en.wikipedia.org/wiki/The_Evolution_of_Cooperation). But this is not the fundamental mechanism of evolution, and every now an then a gene "defects" and does what is best for it at the time. Cancer is an example of this.
Re: When sexual selection can lead to a decline in the capacity for survival
#8I will just echo the other posts here that the author of this article or his sources severely misunderstand natural selection and the special case of sexual selection. The most important thing to understand about evolution is that natural selection can only work with the existing traits of an organism, the current environment in which the organism exists, and what random changes happen. Furthermore, every change in the phenotype of an organism has a number of sometimes disparate impacts on its likelihood of reproductive success within its own environment. Given all of that, we should _expect_ to see seeming contradictions like this example.
Most birds can fly because their parents could fly. The genes for flying stick around because so many other traits of birds have evolved to benefit or rely on the ability to fly. But that doesn't mean flying itself is some magical end goal. Flying is only useful for natural selection insasmuch as it grants the organism a better likelihood of reproducing.
Why would natural selection necessarily prefer birds that are ideally designed for flying in what we perceive as a graceful manner? In fact, we know that it doesn't. Ostriches, emus, and penguins can't fly, though their ancestors were able to. That is not evidence that they are evolutionary dead ends. The huge variety of penguin species that have evolved since the ancestor of penguins lost the ability to fly proves the opposite, in fact.
This bird clearly flies well enough to continue to survive. If the traits that work against it flying gracefully grant it more reproductive success than flying slightly better would, then natural selection will favor those traits.
Natural selection is often treated far too preciously. Sure, it took a genius in Darwin to identify and clearly describe the phenomenon, but the process itself is tautological. It comes down to, "the things that reproduce better reproduce better". This bird exists, therefore natural selection favored its traits. If we don't understand why, the failure is ours, not natural selection.
Re: When sexual selection can lead to a decline in the capacity for survival
#9Earlier quoted context omitted.
You're describing this viewpoint: https://en.wikipedia.org/wiki/Gene-centered_view_of_evolutio... however I don't think it's really an accepted (in terms of evidence) theory that explains all evolution. I think most biologists think that evolution selects at multiple levels (although likely the underlying processes are much more complex than just that). After all, no real visible phenotype is truly based on a single…
> You're describing this viewpoint Yes. > evolution selects at multiple levels That's just another way of saying that evolution selects for reproductive fitness with respect to a particular environment. If a gene is part of an organism, then the other genes in that organism are part of that gene's environment. The aggregation of genes into organisms is itself an evolutionary adaptation (as is the aggregation of organ…
I think you're trying very hard to fit the real world into a hypothesis that doesn't make any sense.
Re: When sexual selection can lead to a decline in the capacity for survival
#10I will just echo the other posts here that the author of this article or his sources severely misunderstand natural selection and the special case of sexual selection. The most important thing to understand about evolution is that natural selection can only work with the existing traits of an organism, the current environment in which the organism exists, and what random changes happen. Furthermore, every change in t…
> the author of this article or his sources severely misunderstand natural selection and the special case of sexual selection.
The author of this article is an Evolutionary Biology researcher at Yale. It would be really weird if he severely misunderstood natural selection.