How Does Biological Evolution Deal With This?

Thanks, @Giltil, for asking a question which prompted others to provide me with a lot of new things I didn’t know. I hope you enjoyed it as much as I have!


Says who???


Seems like an open question is if the fly image on those wings was atypically accurate, not reflecting genetics, just phenotypic variability in this particular fly.

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I think that this is a great example of how things can seem to be quite intuitive, but really are not. I remember when I first visited here some time ago, that’s one of the things that @swamidass and @T_aquaticus said. These patterns that look like flies, for instance, seem to us to clearly be images of flies, but they are just adaptations that have occurred over time. They may serve to look like flies, and, as such, protect or offer some other advantage to the animal who displays them. But, this is also what I was speaking of (or asking about) in the OP… The bug that looks like a torn leaf seems to have been designed to look like a torn leaf. In actuality, its pattern merely developed over time and ended up to look like a torn leaf.

And furthermore, will this pattern end up to be a huge advantage over time and become more prevalent among this species?

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The first word of the title is “Origin.” Do you not understand that English word?

They aren’t that new. You’re also ignoring the primary mechanism for light/dark changes. Why is that?

How much variation is already present in the population? You aren’t assuming that there is no existing variation between individuals, are you? That would be ridiculous.

You are making that false assumption. Why?

No, we don’t.

False. They hypothesize that it evolved from a transposon and tested the hypothesis. That’s science. You should consider trying it.

Why are you ignoring existing variation?

Why would we assume that?

I’m not seeing any interest in science from you.


I am too. I would hypothesize that it was only mostly Darwinian. I’m confident there would have been plenty of neutral evolution involved.

Have you forgotten about that?


Yes, I enjoyed it. What a fascinating topic!

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IIRC this has actually been observed w.r.t. the eye-spots on butterfly and moth wings.


i think that its a generous assumption that base on what we see in the real world. for instance: we have billions of people in the wrold. and we never seen someone who evolved say a new organ part like a part of a wing or a new part of an eye etc. so the chance to get a new anatomical part is probably lower than few billions. at least from what we can see in the real wrold. do you agree or disagree?

sorry but im not sure what is your argument here. maybe i miss something so please explain again your point.

we never observed a complex biological system evolving in front of our eyes of course.

i think that you are mixing between genetic similarity and genetic identity. as far as i remember if the sequence (between two people) is a bit different then you cant use it at court anymore. even that all people share a common descent. also: have you forgot about convergent genetic evolution?

that is the problem: you cant do that if the new mutation is neutral. in the dice case you choose your goal and ignore all the other results. this cant happen in nature.

i do talking about that. how such a system that can control color change evolved?

You did not understand the analogy. It is merely to demonstrate that the odds of any particular combination of numbers is much more easily arrived at if the process can be cumulative rather than simultaneous.

I would like you to try explain why this could not work if the mutation was neutral.

There are times when conclusions are intuitive, but are still wrong. The point being, human intuition is fallible. As I often say, we have the scientific method because human intuition can’t always be trusted.

The analogy I often use is water. Rain lands randomly across the landscape, but it consistently finds flows to the lowest elevation without needing guiding from an intelligence. Evolution is much the same where species move towards a more fit phenotype. Every landscape will have a different water drainage pattern, and each species will find a different route towards better fitness. Camouflage is such a powerful adaptation that we see a lot of different paths, and given the gravitational pull towards better fitness it is inevitable that some paths will lead to the adaptations we see.


A new anatomical part is not a new protein. Chimps and humans differ by 40 million or so mutations, and it is obvious that most of those mutations are not going to affect fitness in any meaningful way. This means that the number of mutations that explains the differences between our species is in the 10’s of millions, and perhaps fewer than that. It didn’t take billions of mutations to produce the differences between us.

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We have observed HGT between organisms resulting in a sequence in one organism resembling the sequence in another organism, which is what is being claimed happened here.

No, I haven’t forgotten about convergence, what makes you think that? There are exceptions to just about every rule in biology, but generally speaking (especially when dealing with large sets of sequences), we can take sequence similarity as an indicator of relatedness.
When we find a symbiotic prokaryote living in very close association with cephalopods, and this prokaryote has a transposon in its genome that has a high sequence similarity to parts of a cephalopod-specific gene, it’s perfectly reasonable to conclude that this sequence was transferred from the prokaryote to the cephalopod.
Creationists would probably be fine with this scenario if it wasn’t for the fact that the sequence in cephalopods is functional, as you have an a priori belief that natural processes can’t create new functions, therefore you have no choice but to deny a reasonable inference.

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No one person has ever observed a mature redwood tree grow all the way from a seed. Does that mean redwood trees were POOFED into existence?

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That moment when you realize the person you thought understands next to nothing about a topic actually understand even less.


Much as stochastic gradient descent fits a neural network prediction model over numerous training epochs.

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How does the octopus make light/dark changes?

Do you really not realize, after all you’ve posted (and possibly read) here, that evolution never happens to individual organisms, that it can only happen to populations?

If you don’t realize something this basic, would realizing it change your position on evolution?

[dad dumb joke]

Did you hear about the family who sent their young son off to bording school?

When the boy returned in two years he had grown another foot!

[/dad dumb joke]



of course. the problem is that it cant happen if we need at least several mutations.

so if we assume that one in billion sequences is functional and say that the first mutation is now in the population. what next? we need the second mutation and it will take about billion more mutations. but till we will get the second mutation i think that the neutral mutation will be lost since it will get many mutations that will remove\change it.

maybe. but in this case its irrelevant since we might not dealing with complex system. im talking about new anatomical part.

if the sequence is different and has a different complex function then it might not be the result of HGT.

it just was a rhetorical question.

maybe it is the result of HGT but it depend in many factors (for instance how much the function is different). but i dont want to get into this now. my main point is that some systems need at least several genes and thus probably cant evolve stepwise. so a single gene that evolved from a transposon will not give us a complex biological system.

how is this relevant to the number of mutations?

how is this relevant to the number of mutation that we need to a new anatomical part? and by the way evolution in a population need to start first in individual organism after all.