Evolution by mutation question

[Percivale]

I'm wondering if studies have been done calculating how many mutations would be needed to cause changes such as from dinosaur to bird, comparing that to the rate of mutations today, and how probable those changes were based on the amount of time the fossil record allows. Do we have enough knowledge of genetics yet to determine how many mutations it takes to change a scale to a feather, etc?

As background, I think universal common descent is probably the case, but am not convinced that the major animal types came about only through random mutations and natural selection, rather than divinely guided mutations.

 

[Gracchus]

First of all, to a cladist, birds are dinosaurs, so there is no changing birds into dinosaurs.
What you might be able to narrow down, is just what sort of dinosaur was ancestral to modern dinosaurs, which we call birds. This is not a matter of calculating probabilities. This is a matter of observing just what changes have occurred. But you would have to look at many birds, comparing which mutations made birds and there are no ancestral dinosaurs around for comparison.
So the best you could do is make an "educated guess", and since creationists won't even accept verifiable facts, it would convince none of them.

 

[Gottservant]

Educated guesses amount to either forthright work, or empty promises. (selah)

 

[Gracchus]

Educated guesses amount to either forthright work, or empty promises. (selah)

That might be true except among creationists to whom their own guesses, usually uneducated, are the proper interpretation of the "Word of God", while those of actual biologists are just guesses because, after all, facts can be interpreted however they would like.

 

[sfs]

I'm wondering if studies have been done calculating how many mutations would be needed to cause changes such as from dinosaur to bird, comparing that to the rate of mutations today, and how probable those changes were based on the amount of time the fossil record allows. Do we have enough knowledge of genetics yet to determine how many mutations it takes to change a scale to a feather, etc?

As background, I think universal common descent is probably the case, but am not convinced that the major animal types came about only through random mutations and natural selection, rather than divinely guided mutations.

Since we don't generally know the number of mutations needed to change one functional form to another, that's not a calculation that can be done. We do know that observed mutation rates provide a pretty good explanation (within a factor of two, at least -- there's still lots of uncertainty in these things) for the total genetic difference between closely related species; we just can't say which specific genetic differences are functionally important.

The other thing we can do is look at evolution on different time scales. If you impose some kind of natural selection in an experiment, either in the lab or by doing something like introducing a new predator into a stream, you can see morphological change happening very fast indeed. If you look at newly introduced invasive species, they change in their new environment, somewhat slower than in experiments, but still very fast. Looking at the fossil record, change during adaptive radiations (when some group of organisms is taking over new ecological niches, as after a mass extinction, say), change is slower still. The slowest change of all occurs for ordinary evolution in fossils, like in dinosaur to bird, which is many orders of magnitude slower than change at short time scales. So there's no obvious reason why dinosaur to bird should be difficult; there's plenty of time for lots of mutation to happen.

(By the way, it turns out that dinosaurs already had feathers, so that change isn't relevant to dino/bird evolution.)

 

[Percivale]

Since we don't generally know the number of mutations needed to change one functional form to another, that's not a calculation that can be done. We do know that observed mutation rates provide a pretty good explanation (within a factor of two, at least -- there's still lots of uncertainty in these things) for the total genetic difference between closely related species; we just can't say which specific genetic differences are functionally important.

The other thing we can do is look at evolution on different time scales. If you impose some kind of natural selection in an experiment, either in the lab or by doing something like introducing a new predator into a stream, you can see morphological change happening very fast indeed. If you look at newly introduced invasive species, they change in their new environment, somewhat slower than in experiments, but still very fast. Looking at the fossil record, change during adaptive radiations (when some group of organisms is taking over new ecological niches, as after a mass extinction, say), change is slower still. The slowest change of all occurs for ordinary evolution in fossils, like in dinosaur to bird, which is many orders of magnitude slower than change at short time scales. So there's no obvious reason why dinosaur to bird should be difficult; there's plenty of time for lots of mutation to happen.

(By the way, it turns out that dinosaurs already had feathers, so that change isn't relevant to dino/bird evolution.)

(I knew that some dinosaurs have feathers, it was just a randomly chosen example)
Do you have links to those studies about invasive species changing or experiments?

 

[sfs]

(I knew that some dinosaurs have feathers, it was just a randomly chosen example)
Do you have links to those studies about invasive species changing or experiments?

This paper, although old, provides a summary of the various evolutionary rates. If you can't get access to the paper, send me an email (sfs@broadinstitute.org) and I'll send you a pdf. You might also want to look at this.

 

[SkyWriting]

As background, I think universal common descent is probably the case, but am not convinced that the major animal types came about only through random mutations and natural selection, rather than divinely guided mutations.

God is not an outsider, watching or manipulating.
Our entire future is "history" to Him.


What was the one common source for life?

 

[AV1611VET]

I'm wondering if studies have been done calculating how many mutations would be needed to cause changes such as from dinosaur to bird, comparing that to the rate of mutations today, and how probable those changes were based on the amount of time the fossil record allows. Do we have enough knowledge of genetics yet to determine how many mutations it takes to change a scale to a feather, etc?

I'm sure if they did, they could have met my daisy-chain challenge: 1

At least on paper.

Instead, biological evolution allows for "missing links," while still claiming we're all related.

That's probably why it's just a theory.

 

[Audacious]

I'm sure if they did, they could have met my daisy-chain challenge: 1

At least on paper.

Instead, biological evolution allows for "missing links," while still claiming we're all related.

That's probably why it's just a theory.

A scientific theory is the highest official level of evidence in science, requiring a great deal of substantiation. Evolution is considered a fact by 90% of biologists.

Other theories include germ theory and the theory of gravity.

 

[AV1611VET]

A scientific theory is the highest official level of evidence in science, requiring a great deal of substantiation. Evolution is considered a fact by 90% of biologists.

Other theories include germ theory and the theory of gravity.

Does that include Phlogiston theory too?

Or is Phlogiston theory exempt?

How about the seven or so theories as to how we got our moon?

Are they exempt as well?

 

[Audacious]

Does that include Phlogiston theory too?

Or is Phlogiston theory exempt?

How about the seven or so theories as to how we got our moon?

Are they exempt as well?

The colloquial definition of theory is different from the scientific one. Also, there's essentially one theory to how we got the moon.

Phlogiston is a rather outdated theory that has been disproven since the 1780s, and is not considered a theory in scientific terms.

Also: IIRC, we (probably) got the moon as part of the Giant Impact Hypothesis, when Theia (a Mars-sized object) collided with the earth.

 

[AV1611VET]

The colloquial definition of theory is different from the scientific one. Also, there's essentially one theory to how we got the moon.

Phlogiston is a rather outdated theory that has been disproven since the 1780s, and is not considered a theory in scientific terms.

Also: IIRC, we (probably) got the moon as part of the Giant Impact Hypothesis, when Theia (a Mars-sized object) collided with the earth.

I wasn't aware that Phlogiston theory was just a colloquial theory.

But for the record, I take it you're stamping EXEMPT on all these?

Or am I wrong?