I helped Cecil research the question.
And here I thought you only did feathers…
What about them? Bats evolved bats that could vocalise, and they in turn evolved form insectivores that could vocalise, and they in turn evolved form reotile-like ancetsors that coudl voclaise, and they evolved form amphibians that could vocalise.
I’m assuming you aren’t claiming that bats infact evolved their ability to vocalise independently of all thier non-echolocating ancestors?
That’s like saying that a caveman is going to invent the screwdriver in tandem with the wheel and the internal combustion engine in order to build a motorcar.
Evolution acts by seclection of pre-existing triats. It can’t produce fully functional traits out of nothing specualtively, much less three related traits.
Let me put it this way, does your proposed organism develop a voice first with absolutely no ability to interpret or hear the sound produced? If so then how does that provide a survival advantage? Or does it produce the necessary interpretation centres in the brain first, with absolutely no ability to hear or even produce the sounds that it might interpret with it? If so how does that provide a survival advantage? Or does it produce the recieveng apparats first, with no ability to produce or interpet the sound sthat unit might receive?
Theres no conceiveable way that it could happen. The organism needs to have a pre-existing sound production and recieving system in place for selection to work on tor produce an echoloctaion system. You don’t evolve the ability to produce echolocation noises when you have no ability to interpret those noises. What you can do is have the ability to make noises to communicate and the gradually modify it from that use into an echolocation system.
Complicated systems like the eye and echoloction systems can be poduced by evolution, but they can’t be produced ex nihilo. They can only be produced by a gradual series of modifications from pre-existing structures with other functions. If the component structures have no function in their earlier form the entire system can not be produced.
If the ability to produce sound is not useful before the echolocation system is produced then the echolocation system itself can not be produced. This is the same as the way that the ability to percieve light had to be useful before the eye evolved, in order for the eye to evolve. Organisms didn’t evolve eyes in tandem with an abiity to detect light. They evolved eyes because they could detect light. Similarly you don’t evolve the ebility to produce sound in tandem with the ability to see with it. You evolve the ability to see with it because you can produce it. If you can’t produce it you can never evolve the abiity to see with it.
Well, we can see light even though our bodies don’t produce it. But I see what you are saying.
Umm, light isn’t sound. It’s quite diferent. Light is elctromagnetic radiation. Sound is a physical virbation transmiited thorugh the air.
Good… I think.
Why is it different? Eyes see by the light in the environment. There is sound in the environment independent of any ability to cry/scream/hoot/etc. Why can’t the ability to see by sound evolve to match the way seeing by sight evolved?
Zombie thread.
And the answer is because “seeing” sound is what we call hearing. It’s not something different.
You can’t posit that an organism could evolve the ability to hear because the ability to see sound is useful. That’s a tautology. It’s like positing that an organism could evolve the ability to see light because vision is useful. It might be true, but it doesn’t tell us anything.