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I think it is quite plausible that feathers originally developed for thermoregulation. If they started as simple filaments that could be raised and lowered to adjust radiative surface area, it seems that thermoregulatory advantages alone could have driven a series of small evolutionary improvements towards flat, light-weight feather-like structures. Seeing a bird able to massively fluff up its feathers or pull them in tight against its body is like seeing a person instantly go from wearing a puffy down coat for winter to a sleek body suit for summer exercise. From there, I can imagine how these flat, controllable surfaces could be used by small animals to eventually control rapid descent from trees to escape prey and then eventually evolving to flight.

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Or even courting rituals! I like that route because, something terribly unrelated to survivability (ostentatious display can attract predators, signals mating suitability because the male can survive the cost of the display) becomes a wonderful adaptation. No evidence for this of course, but it makes a great just-so story

We can certainly explore that theory, but what can you suggest as falsifiability criteria? Flight evolved several times, presumably, including in insects and in mammals without feathers:

https://ucmp.berkeley.edu/vertebrates/flight/bats.html

Notice:

We can infer that bats gradually evolved true flight from a gliding arboreal ancestor, possibly using the gliding membrane as a sort of "net" while the flight stroke evolved.

We can infer this because we beg the question, i.e. the only way evolution can happen is random mutation and natural selection. And so, we postulate the theory as true fact and then we get the result that it must have happened some way that is consistent with the theory.

I am just generally remarking on the fact that all that seems to be required in today's scientific environment is to describe what could have happened with some arboreal ancestor gaining, say, webbed wing-like arms for some reason, and then over thousands and millions of generations for some reason, before the webbed arms could help them glide, they were accepted instead of shunned by their mates for their mutation, and the mutant population survived and genetically drifted in that direction, until finally they could glide... and then fly.

I suggest no falsifiable criteria at this time and I likely never will. I merely point out intellectually interesting plausibility. If you restrict all of your consideration to only those things you already know how to prove or disprove, I think you severely limit ultimate discovery. Sure, you want to strive for determining truth, but I think it starts with curiosity, brainstorming, and inspiration. By the way, even snakes have figured out how to fly, or at least glide pretty well (see https://en.wikipedia.org/wiki/Flying_snakes).

It could be falsified by finding fossil evidence of ancestors that had no flight yet, did have feathers, but had some other mechanism of thermoregulation sufficient for their needs.

The fossil record is incredibly limited and I'd bet against such a fossil ever being found even if the animal existed, but in principle it is a falsifiable theory.

Well in principle string theory is falsifiable too. But at least string theory has a lot of math that always seem to work out. Here we have a bunch of stories and a lot of politics.

When the stories don’t even make consistent sense (eg how do exclusively gay or asexual people exist if many theories of evolution predict such a trait would have been practically weeded out of the population by now, but it keeps coming back) people grasp at straws to say “well it HAS TO have SOME fitness advantage” because they just stick to the same basic theoretical framework no matter what the data says.

Does evolution even predict that it would have been practically weeded out? As far as I know we don't even know what causes people to be gay.

Some things can't be weeded out by evolution, e.g. we will never lose major traits that are developed in the first weeks of an embryo's development, as everything that develops in the later stages depend on the first.

Non-hereditary traits aren't obviously weeded out either, and I don't think homosexuality is (always) hereditary.

Has there really been any research by evolutionist biologists suggesting that homosexuality should have been weeded out and it's an anomaly in our theories?

> As far as I know we don't even know what causes people to be gay.

We don't know what causes people to be straight either, but that doesn't seem to stop evolutionary biologists proposing evolutionary explanations for the existence of straight sexual desire.

> eg how do exclusively gay or asexual people exist if many theories of evolution predict such a trait would have been practically weeded out of the population by now, but it keeps coming back

Evolution works on populations not individuals. Exclusively gay people are the non-breeding worker ants of humanity, they don't pass their genetics along but the do their bit for the survival of the colony. That's only if there is a genetic component to homosexuality of course, which is heavily disputed.

> Exclusively gay people are the non-breeding worker ants of humanity, they don't pass their genetics along but the do their bit for the survival of the colony

And that's a just so story. There is zero evidence that this actual reason for the continued existence of non-heterosexual humans in the population.

It's not clear to me that same gender attraction requires any more of an explanation than opposite gender attraction. It's only a particular, narrow evolutionary lens that makes homosexuality look like a puzzle to be solved, rather than a fairly obvious consequence of the fact that people of the same gender can get each other off and have feelings for each other.

Honestly, we gays seem to have the worst luck in this respect. A couple hundred years ago people didn't think we fit into "God's plan". Now they agonize over how exactly to fit us into evolutionary theory. (I think there are about as many theories of the evolutionary origins of homosexuality as there are evolutionary biologists.) Hamlet got it right: "There are more things in heaven and earth...Than are dreamt of in your philosophy".

> There is zero evidence that this actual reason for the continued existence of non-heterosexual humans in the population.

I'm not looking for evidence of their continued existence, I was correcting the parents incorrect claim that evolution would eliminate homosexuality.

> rather than a fairly obvious consequence of the fact that people of the same gender can get each other off and have feelings for each other.

The fact that we want to get each other off at all is driven by evolution, a species that doesn't have an urge to get each other off goes extinct pretty quickly.

> Honestly, we gays seem to have the worst luck in this respect. A couple hundred years ago people didn't think we fit into "God's plan". Now they agonize over how exactly to fit us into evolutionary theory.

Really, you think quest for knowledge is at all comparable to the 2000 years of active persecution?

> The fact that we want to get each other off at all is driven by evolution,

This begs the question. Gay sexual desire is a counterexample to this claim.

> a species that doesn't have an urge to get each other off goes extinct pretty quickly.

Evolutionary considerations may set boundary conditions. It doesn't follow that the sexuality that humans in fact have has an evolutionary explanation.

There's a dilemma here. If you're going to paint a picture of evolution as a ruthlessly fitness-optimizing process, then you have to take gay sexual desire seriously as a counterexample.

If, on the other hand, you accept that evolutionary theory per se only rules out extreme possibilities (e.g., a completely asexual species that reproduces sexually), then you also have to accept that the specifics of human sexuality may not have any explanation in evolutionary terms.

>Really, you think quest for knowledge is at all comparable to the 2000 years of active persecution?

The persecution of gay people continues. Non-religious bigots will often justify it on alleged evolutionary grounds ("it's not natural"), just as religious bigots will often justify it in terms of Biblical proscriptions.

We start out by acknowledging that we cannot know with certainty. That is always Step One in science -- any science -- biological, atmospheric, physical.

Pointing it out doesn't make you edgy, it just makes you a PITA. You're still on Step One while we are working on the implications of "suppose x:y:z", having ruled out "x:w" sometime back, and "x:y:v" more recently.

Could it be "a:b:c", instead? Maybe, but that would require a to overcome all the problems x satisfied, lo those many years ago, before we embarked on y and z.

Call back when z and all its other alternatives, and the other possibilities given x, have been ruled out. Unless of course you have good evidence calling x in question, that nonetheless accounts for its apparent successes.

Reflexive skepticism and gullibility are two sides of the same plug nickel.

This sounds like enthuastic and vigorous excuses for the fact that these theories are not falsifiable and even worse than phlogiston and luminiferous ether theories. Why such a full throated defense of them? I think because you want to get as far away from creationism as possible, as quickly as possible. “We are working on it! Shh!! One day I am confident we will know!”

No. I start out confident that we will never know, but can only surmise based on available evidence, and continue seeking further evidence. Further evidence can require revisiting choices -- even all the way back to the beginning, although that would need to be pretty big evidence.

The only alternative is the familiar, and very popular, self-deception; and its familiar companion, deception.

Well, Dawkins and other prominent promoters of modern evolutionary synthesis usually say the opposite: we are working on it, they say, and we BELIEVE one day we will know the answers to what right now we don’t!

They even derisively call any religious explanation a “god of the gaps” argument.

Richard Feynman says scientists are responsible to avoid self deception. Being able to admit your just-so story is currently unfalsfiable and is actually more similar to a fifth grade writing assignment than to science, is part of that responsibility.

I don't answer for Dawkins.

The difference between scientists and you is the difference between real work and hot air.

Go actually do something. Something hard, that takes real understanding, real work, and trial and error, failure and trying something else until you get somewhere no one has ever been. Something that involves more than talk.

Please don't cross into personal attack no matter how wrong someone is or you feel they are. We've had to ask you this before. We eventually ban accounts that do this, and your comments in this thread were consistently more flamewarrish and aggressive than anyone else's (that I saw). That's not cool. Would you mind reviewing https://news.ycombinator.com/newsguidelines.html and sticking to the rules from now on?

Sure thing.

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