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[flagged] Beauty Is Making Scientists Rethink Evolution (nytimes.com)
36 points by pdog 8 months ago | hide | past | web | favorite | 45 comments

> Although never completely forgotten, Darwin’s theory of beauty was largely abandoned.

This claim is completely unsubstantiated - even my high school biology class went over sexual selection as a form of natural selection.

Yeah, I was astonished by this claim. Everyone who knows anything about evolution has heard of sexual selection. There's no real dispute that female sexual preference is a major factor determining male sexual success. The only part that has been rejected is the idea that female preference is completely arbitrary, and I'm not sure anyone ever believed that in the first place.

I was going to say, hasn't all of this been known for a while? I suppose it's worth continuing to publish articles educating more and more of the public on the topic, but the headline is rather deceptive in presenting this as a new concept.

The writers of this piece don't even seem to know what evolution of species is. Evolution has as a premise the survival of species. To survive, reproduction is the most important consideration. Therefore, beautiful specimens (itself a subjetive notion created by evolution) have the tendency to reproduce more often and make it possible for the species to survive.

"Adaptations are meant to be useful — that’s the whole point — and the most successful creatures should be the ones best adapted to their particular environments."

No, they aren't. Adaptations aren't even meant to be viable. Statistically, what they trend towards is not the "objective" of usefulness, but of reproduction. As a consequence of that end, this tends to include traits that aid in personal survival, attracting a mate, and ability to nurture, protect and provide for the offspring. Beauty, while in the eye of the beholder, obviously fits into the role of "attracting a mate." Usefulness not required.

This is a common misconception thanks to the term "survival of the fittest". Evolution is a blind dumb statistical optimization by virtue and ONLY by virtue of creatures managing to reproduce. Anything that changes relative rates of reproduction changes relative distributions of genes and that's the end of the story.

Nature doesn't design, foxes are not "meant" to hunt hares and hares are not "meant" to evade foxes. It happens that the hares that evade foxes and the foxes that eat hares are more likely to survive to pass on genes. Creatures with an aversion to asymetrical (a proxy for unhealthy) mates are more likely in the long run to have healthy offspring...and so on and so forth.

The critical mistake is people adding "intentions" and "meaning" to a blind dumb statistical process akin to Russian roulette.

I think the notion of local minima fits into this. It might be optimal for male birds of some species to have very colorful flair to attract females. Within that species of birds, these males with the more colorful/visible/expensive plumage will be selected for. This will remain true on shorter evolutionary time scales. It will work for a while. However, if the males of the species develop flair that becomes too attractive to predators or makes them incapable of outrunning said predators, and most males get eaten, natural selection will ensure that things balance themselves out. That species of birds could go extinct, or it could be that there are very few colorful males left, and the females who are less selective win out because reproducing with the males that are left is better than not reproducing at all.

Evolution is non-stationary. What's making an individual fit depends on its current environment here and now: the food it can find, what predators are out there, things that make it more attractive to mates. However, predators, food, weather and mates change over time. In other words, what's being optimized for is constantly changing, there are local dynamics and some amount of "noise" that occurs, possibly resulting in silly looking animals like peacocks happening once in a while.

But a male who can be visible to predators and yet still survive must have something else (what?) that makes him more valuable.

I think you're overselling your argument a bit—the existence of one mechanistic explanation for a process doesn't 'crowd out' other descriptions.

Descriptions can be dual—saying foxes are "meant" to hunt hares, or predators are "meant" to hunt prey, can just be a compact way of describing their long, mutual historical co-evolution. Certainly, if you remove all prey from an environment, the foxes would die. What could be more meaningful (to the fox) than survival?

For example:

Mental thought is just a dumb statistical phenomenon that is a product of competing neural synapse electrochemical potentials, neurotransmitter levels, and ultimately subject to the dumb, unthinking hand of physical law at the subatomic level. Anything that changes the movement of particles and energy in your brain changes the neural outputs, and that's the end of the story.

Brains don't think, minds do not regard themselves, piles of dumb atoms to do not feel pain, love, or happiness. It just so happens that brains that create output patterns that, when input into other brains, cause mutual feedback loops of interaction. Creatures that mutually interact are often more likely in the long run to have healthy offspring, and thus over time we would expect to see more brains like this.

The critical mistake is people adding "meaning" and "thoughts" to a blind dumb statistical process akin to Russian roulette.

> saying foxes are "meant" to hunt hares, or predators are "meant" to hunt prey, can just be a compact way of describing their long, mutual historical co-evolution. Certainly, if you remove all prey from an environment, the foxes would die. What could be more meaningful (to the fox) than survival?

This approach uses 'meaning' / 'meant' in two very different ways:

1) the process of co-evolution over time

2) a fox's concern for its own existence

Overloading like this doesn't add clarity, in my opinion, especially when the term 'meant' implies to most people some sort of intent-driven process.

The critical mistake is ignoring irreducible complexity to extrapolate micro evolution to macro evolution.

Newspaper science writing works on much the same basis as natural selection - its role is to engage readers first and foremost and succeeds in reproducing the content in their minds and social media accounts only if it grabs their attention first!

This article is a pretty classic example of that. It starts with misconceptions about what evolution is and the cliche of the brave scientists criticised by the establishment for even raising the possibility of sexual selection. Then it moves on to acknowledging that not only had sexual selection theory has been around since Darwin but it was frequently discussed until eventually support was found for hypotheses that aesthetic preferences animals had evolved to acquire were likely correlated with traits [originally] useful for survival. Then we get to meet the brave scientist challenging the establishment and conclude that much of his lack of peer approval for his views on beauty might stem from his apparent disinterest in engaging with these theories. Then finally, we're presented with the idea that since even our standards of beauty are down to the evolution of the eye of the beholder, the scientific establishment was probably right all along. The article wouldn't have won the affections of the editor if it had started out with that argument though...

So bloody true and so bloody annoying. I started to block the media outlets that do that in my Google "swipe left on pixel home screen" feed or whatever it's called. Until I realized it's a futile struggle and just disabled the feed entirely.

I'm really at a loss of where to get my news. So far, I switched to HN comments. If you know of anything better please share!

No easy answers, but Quanta is definitely one of the better ones. It's funded by a non-profit and writes fairly deep pieces (for a lay audience) on maths, physics and biology.

Agreed. I actually forgot about it, subscribing now. Ironic that the only good publication is free and has no ads.

And like any other multi-agent self-interested system, you run into weird "market failures", where say, female lions start noticing that healthy male lions tend to have scruffy, luxurious manes, so male lions start prioritizing the growth of a scruffy, luxurious mane over other, potentially more "useful" traits.

Which, ironically, also works out for them in another way--during the current Holocene extinction, for example, "convincing the humans to spare you from their rapacious reshaping of the entire planet" is quickly becoming a key evolutionary adaptation, which may very well end up saving otherwise completely useless animals like pandas or chickens, as well as other "charismatic megafauna" like lions. It may have already saved elephants--since antiquity, there have been a fair number of human cultures that venerate elephants for one reason or another, which is a pretty good evolutionary niche if you can get it.

Household cats.

You get to exercise your ancestral proclivity to hunt mice and small birds. You get to eat what you hunt.

You don't have to stay in the humans' house, they'll make a hole in their own dwelling just for you. And they won't mind if you go out, just like their teenager.

If you don't find more food than you need, the humans will feed you.

All in exchange for... rubbing your belly now and again.

That is an evolutionary jackpot.

Although perhaps the real hero is the toxoplasma, a brain parasite that originates in the feline digestive tract that has an extraordinary adaptation to infect a mammalian host and cause compulsive cat-seeking behavior. While there’s relatively little controversy that this can infect mice and lead them to disregard their own safety to approach cats to be eaten, there are some indications that it may be the culprit in cat-loving behavior in some humans as well.

And that’s as good an explanation as any, since cats are remarkably useless otherwise. A small, trained dog can hunt mice and rats more effectively, though there is some benefit to the relative autonomy of the cat when you consider the role of barn cats or ship’s cats. Cats living in close contact with humans definitely seem to benefit from those humans developing some hard-to-explain fondness for them. Yes, they’re so cute and fluffy and precious, I recognize that, but that’s exactly what I would say if I was infected by a brain parasite that wanted me to ensure the survival of its host.

> And like any other multi-agent self-interested system, you run into weird "market failures", where say, female lions start noticing that healthy male lions tend to have scruffy, luxurious manes, so male lions start prioritizing the growth of a scruffy, luxurious mane over other, potentially more "useful" traits.

Concrete example: Peacock tails

This line switched me off too.

'Survival' means genes being present in future generations. If all the females suddenly preferred males with a certain weird beak shape - that beak shape would propagate.

The opposing pressure would be how much other aspects of life would reduce the opportunities weird beak males had to breed.

> the "objective" of usefulness, but of reproduction.

The entire article specifically emphasizes how the issue is much more subtle than this - there are traits that are 'beautiful' precisely because they signal to potential mates that this individual is healthy, and therefore well-adapted to the environment.

This is a really important point. Evolutionary psychology and associated disciplines have come to replace psychoanalysis and God in the popular imagination as a teleological force that's making rational decisions about what to do in a given moment. This makes it into a bludgeon for reinforcing the status quo (just as the other two were before that).

While I'm not necessarily 100% in agreement with this formulation, I do think a useful and simple corrective is this: "natural selection" isn't a positive choice for the "fittest"- it's the elimination of unfit adaptations before they can be passed on. This article references "sexual selection", which may well be a positive choice, but it has very little to do with utility or health, as I'm sure many of us recognize from our own lives and the studies of animal mating choices.

Why would you dismiss evolutionary psychology outright? Case in point, rabbits are typically extremely skittish, and that seems to serve a function. In chimps, overly aggressive males tend to dominate packs, but if they're compromised in any way, the other chimps tend to brutalize them. The entirety of most complicated animals' mate selection process is highly predicated on psychology...why would human psychology not be subject to similar systems?

It's easier to go with the psychology of women, as they're the "discriminate selectors," in most species, and humans are no exception. If you disagree with this, you are not aware of dating site data. A good example of a psychological trait involved in attraction is that a woman will often find a man having a good sense of humor as being sexually attractive. A reasonable cause is that a good sense of humor is often a proxy for intelligence, pattern recognition, and creativity. Finding this to be an attractive characteristic very likely assisted in the evolution of the species by serving as a basic proxy for useful survival attributes.

Unless I'm misunderstanding you, it strikes me as odd to simply dismiss an entire element of gene expression as somehow not having been subjected to similar principles as others.

Evolutionary psychology got a bad rap for writing a bunch of "just-so" stories. Without experiments or the confirmation of predictions, it is very easy to fall in to the trap of inventing a story that makes sense to people when they hear it but that isn't particularly aligned to the truth.

Inventing stories that activate the culturally and individually subjective feeling of "that makes sense," is the lowest form of knowledge-seeking. Now, I'm not judging whether or not the accusation is deserved, but that's the substance of the bad reputation.

I didn't dismiss evo psych outright in that comment- I said it's often being used in the way psychoanalysis and theology were being used to naturalize the current social order. Though you do engage in the kinds of problems that I was trying to outline in this comment. That is to say, you're looking at social phenomena and then working backwards to make unfalsifiable claims that it may be beneficial using a lot of cultural intuition rather than hard data. While I don't find the implications of your feelings about humor particularly problematic, it's the same process that leads to more harmful ones.

As others have noted in the thread, it's just as possible that a predilection for humorous mates isn't such a deleterious adaptation that it kills the people who have it before they die. It may well serve no practical function, and it doesn't need to.

I'm definitely not saying it's not interesting to look at the ways that a penchant for humor manifests itself across species and cultures and whether there are any genetic markers that determine whether somebody is more or less interested in a humorous mate. At that point, it'd be interesting to see how those markers were propagated over time, when they developed, etc. Otherwise, though, this just does the same thing as psychoanalysis and theology- it takes the current order and asks how it fits the narrative you've already assumed.

I would've thought that the traits that you are psychologically brainwashed into believing are desirable will be the traits that you see propagated... selective breeding.

This will mean that if we're brainwashed into believing that a certain model of "beauty" is the most desirable to breed with, that's what we will breed with. Over time, these traits will become predominant.

If certain adaptations are desirable, they will continue to be propagated, if they're not, they won't.

I dont really understand the point of the article

It covers all the bases and masquarades sexual selection as separate from natural selection without ever drawing a conclusion on whether that antiquated notion has merit now or not

It is well established that “beauty” is just an extreme of physiology as a preference that can only exist because it reproduced, if it is otherwise useless for survival

So it isnt new to look at these things this way so what are scientists rethinking and who are these people

Correct. As evidences by modern architecture when you aim for utility then you get neither beauty nor utility, because people do not want to inhabit an ugly place, but if you aim for beauty you will get both.

Beauty transcends the living into a state it could not achieve by mere utility.

What about blindness or deafness?

That's why I said that traits don't even have to be viable, they just don't have to prevent the propagation of genes. Those are either the result of random mutation, are the result of recessive genes that didn't manifest in the parents and therefore didn't present any bearing on their ability to reproduce, or simply just weren't problematic enough to impact reproduction. There's also the possibility that they're not related to genetics at all. It all depends.

Those traits have clearly not been selected for, though, they've simply been rare enough to be tolerated in the gene pool.

hmm I see what you are saying. Thanks.

Probably the most interesting representation anything related to this I've seen is the stalk-eyed fly[1]. Their compound eyes are at the end of long stalks, and apparently the primary reason for this is to attract a mate.

1. https://en.wikipedia.org/wiki/Stalk-eyed_fly

I think a lot of critics of the article in these comments bailed out of the article partway through.

The article is an examination of the origin of sexual selection. Are sexually selected traits linked to adaptive traits (originally, even if they later run away and become maladaptive), are they mere random chance, or is the truth more complicated than either of those theories?

There is nothing new in this article causing scientists to rethink Evolution. Sexual selection, on the basis of physical traits (weaponry or ornaments), has been known and observed since Darwin. Evolution doesn't produce the best adaptations to a given environment. Rather it produces the least worst. Reproduction of genes through generations is the name of the game.

Evolution produces random features, which remain as long as you survive and reproduce.

So you may get totally ornamental or vestigial or obsolete features simply because they were never enough hindrance to reproduction. "Enough" is a key word - even features which are hindrances but do not offset pro-survival/pro-reproduction features will remain.

One thing I don't understand is how one species can appreciate the ornamental features of another. Human aesthetic criteria may direct the development of human features, but why do our aesthetic criteria positively appraise the features of many animals that we did not influence? One example would be birds, which are very beautiful but aren't even mammals.

Ornamental features are not obsolete. Many animals are selected for their ornamental features, which may act as heuristics for fitness (both for the opposite sex in reproduction and for the same sex in combat/competitiveness). I know not all of the book is still considered wholly accurate, but Dawkins describes this at length in The Selfish Gene.

True - ornamental was the wrong choice of wording. Ornamental features absolutely aid sexual selection.

Indeed. It's alarming that such basic scientific literacy is eluding editors at the NY Times.

Yes exactly this.

There are volumes and volumes on the changing nature of sexual selection over millennia by different species. It's striking that NYT would make this sound much larger than it is.

So nothing to see here?

TFA would indicate otherwise...

> Many of Darwin’s peers and successors ridiculed his proposal. To them, the idea that animals had such cognitive sophistication — and that the preferences of “capricious” females could shape entire species — was nonsense. Although never completely forgotten, Darwin’s theory of beauty was largely abandoned.

Except that it wasn't. Sexual selection has been well-established as a process within natural selection for decades.

It's also so obvious as to not even require evidence, honestly. If evolution is the propagation of certain gene adaptations through reproduction, then it goes without saying that any discriminatory element resulting in successful or unsuccessful reproduction, wherein the gene expression has an impact on the outcome, is necessarily involved in the existence of that trait.

Indeed. Sexual selection is the principal topic of Darwin's “Descent of Man.”

A very interesting question but the article is so bloody huuuuge!

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