
Feathers came first, then birds - lelf
https://phys.org/news/2019-06-feathers-birds.html
======
ncmncm
Kind of obvious, of course.

For a while there was a "Birds Came First" insurgency, insisting birds were
not in Dinosauria because ... well, because they liked birds but hated
dinosaurs? The argument never made sense, and it finally died down.

People who like birds and hate dinosaurs are like people who like tetrapods
and hate fish. It's allowed, but not something for vertebrate biologists to
pay attention to.

------
Balgair
_PBS 's Eons_ is a great Youtube channel that covered the evolution of
feathers.

[https://www.youtube.com/watch?v=aOeFRg_1_Yg](https://www.youtube.com/watch?v=aOeFRg_1_Yg)

------
mikorym
I thought that this was known already? But I guess that this is the _Feathers
Could be First (2019)_ version.

------
fit2rule
So, this settles it. The egg comes first.

~~~
misnome
It's always been the egg. The egg is laid by a proto-chicken and has the
genetic mutation required to tip it into the "chicken" classification.

~~~
saalweachter
Is a chicken-egg an egg laid by a chicken or an egg that yields a chicken?

~~~
philbarr
Nice try - but the original question doesn't state the egg has to be a
chicken-egg, just "the egg".

~~~
ukz
But a bird's heavier than feathers.

~~~
sbarker
But when birds of a feather flock together, many hands make light work.

~~~
stronglikedan
And it's known that a bird in many hands is just a gross bunch of fleshy bits
with feathers sticking out.

------
EGreg
Seriously though, I have done a bunch of “wikipedia research” on how flight
evolved. It’s all a bunch of “just so” stories and theories, which struggle to
prove any evolutionary advantage to intermediate forms that can’t achieve
flight or even gliding.

I think the evolution of flight is one of the clearest examples that the
standard theories of evolution purely by mutation and natural selection are
still lacking explanatory power. I understand that the theory of Common
Descent has ample evidence but let’s not conflate that with the other theories
(about HOW genetic drift happens in macroevolution) and turn “evolution” into
a religion in our quest to replace creationist accounts. It is a catch-all
umbrella term to describe many theories, from “punctuated equilibria” to the
“modern synthesis”, which still are in their infancy as the luminiferous
aether or phlogiston as physical theories.

I find there is too much suppression of dissenting views in evolutionary and
climate science, for my taste. I am talking about universities and publishers
taking concerted _political_ action against what is perceived as going against
the current establishment.

 _A new scientific truth does not triumph by convincing its opponents and
making them see the light, but rather because its opponents eventually die,
and a new generation grows up that is familiar with it._ \- Max Planck

In many circles, publishing anything critical on scientific grounds is like
publicly criticizing capitalism in USA or Islam in Saudi Arabia. A lot of time
you get instant downvotes and hostile responses from laypeople.

If you’re curious what I’m talking about, here is probably one of the better
treatments of the mathematics behind current theories, for example:
[https://www.amazon.com/dp/1880582244/ref=cm_sw_r_cp_api_i_r....](https://www.amazon.com/dp/1880582244/ref=cm_sw_r_cp_api_i_r.M9CbRRG16AF)

~~~
1e-9
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.

~~~
EGreg
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](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.

~~~
Scarblac
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.

~~~
EGreg
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.

~~~
Scarblac
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?

~~~
foldr
> 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.

