Freethought & Rationalism Archive

Duvenoy · 08-17-2003, 08:07 AM

Aha! Found it! I'm re-posting it here mainly for the links, which I think are very good.

Quote:

Originally posted by DMB
"Charles Darwin" seems to be arguing the irreducible complexity of bats' echo location here.

I was hoping.....

The fact is that not all bats echolocate. The old world fruit bats don't use it. Rather, they have evolved enhanced eyesight. I think there is a single species that echolocates, but it is with tongue-clicking, rather than through the larynx.

Echolocation ain't all that rare. Toothed whales do it, the tenrecs of Madagascar and some species of shrew, non-fliers all, also do it.

One wonders how many times it evolved, in one form or another, over the ages.

Interesting sites:

http://www.tenrec.org/fieldolson.htm

http://www.pubmedcentral.nih.gov/art...gi?artid=33452

doov

Charles Darwin · 08-17-2003, 04:42 PM

Quote:

Originally posted by Duvenoy
The point is that the extinct bat was very old -- are you YEC?

I don't see how evolution is a fact no matter how much time you have. In other words, I don't think the age of the earth has much of a bearing. My point here is that the fact that a bat, with echolocation, is now extinct doesn't add credence to the theory that the bat (or echolocation) evolved.

Quote:

Originally posted by Duvenoy
Also, not all bats echolocate, and, with one exception, those that do use the larynx to produce the sound. The other, one of the fruit bats, uses tongue clicks.

Yes, it now looks like echolocation must have evolved several times. Just like so many other designs.

Quote:

Originally posted by Duvenoy
Further, echolocation ain't all that big of a deal. Many animals have evolved the trait, notably toothed whales, the tenrecs of Madagascar, and some species of shrew. Oddly, bats are the only fliers known to have done so.

Why does the fact that many species make use of echolocation make it no big deal? It sounds like you are presupposing evolution to be true. That is fine if you want to talk to other evolutionists, but it doesn't work if you want to promote evolution.

Quote:

Originally posted by Duvenoy
Seems to me that if echolocation was bestowed upon these animals by some sort of deity, that deity would have also given it to many other creatures, who could use it to advantage.

I thought you just made the point that echolocation is no big deal because it is bestowed upon many different creatures. Looks like you're having it both ways. Apparently what you are saying is that it occurs sufficiently often for it to be no big deal, and yet not often enough to satisfy your opinion of what a deity would do. So now we're about as scientific as yesterday's astrology column. You're making some sort of vague claim that echolocation is no big deal because it is in multiple species (last time I checked echolocation had the US military's systems beat hands down), and then you're telling us about God.

As far as I can tell both these claims are unsupported. Can you help and explain how you found these things out?

Quote:

Originally posted by Duvenoy
On a side note, there are species of moth that take wild, evasive action the instant they hear a bat echolocating. Sound (bad pun! )evidence of natural selection, no?

Yes, indeed, that is evidence for natural selection. By the way, yesterday's astrology column had it right. More evidence for astrology, no?

Quote:

Originally posted by Duvenoy
The fact is that not all bats echolocate. The old world fruit bats don't use it. Rather, they have evolved enhanced eyesight. I think there is a single species that echolocates, but it is with tongue-clicking, rather than through the larynx.

Echolocation ain't all that rare. Toothed whales do it, the tenrecs of Madagascar and some species of shrew, non-fliers all, also do it.

One wonders how many times it evolved, in one form or another, over the ages.

doov

Well, I guess evolution must be true! {/sarcasm off}. Thank you for the links.

Charles Darwin · 08-17-2003, 04:50 PM

Quote from Data: You answered your own question there.

Quote:

Originally posted by Wounded King
The direct observational evidence of evolution, the 'small amounts' of evolution are the changes in allele frequency which secular mentioned.

As a paleontologist rather than a geneticst Gould preffered to discuss the fossil record, but the first tier of evidence he mentions is exactly what Secular described.

You must be kidding me. Don't tell me I'm going to have to suffer through equivocating on evolution and spend a dozen posts clearing that up? If you think evolution is a fact, then explain why. Gould said it is a fact because there are fossils, similarities, and small levels of evolution. Is that really your reasoning too?

Wounded King · 08-17-2003, 05:12 PM

Are you saying that we don't observe microevolution? If so there are a couple of hundred pieces of primary literature I can refer you to.

Why not tell us what you understand by evolution and then maybe we can tell you if it is a fact, you obviously don't like the definition Secular Pinoy gave.

Where does the equivocation come in? In trying to dismiss the evidence as only microevolution.

I personally think that evolution is a fact because of the various microevolutionary experiments that have been performed, the radical changes in morphology associated with highly specific mutations seen in developmental biology, the highly conserved nature of developmental programs and developmental signalling pathways, the fossil record, numerous studies on isolated population which have diversified and speciated (such as the cichlid fish in Lake Victoria) and a whole lot of other stuff that doesn't come to mind at the moment.

Doubting Didymus · 08-17-2003, 05:25 PM

Endogenous retroviral insertions confirming phylogenetic trees constructed on independant data prove that species descend from a common ancestor.

Doubting Didymus · 08-17-2003, 05:32 PM

On the same note, the phylogenetic trees formed by standard genome comparisons confirm the trees built by morphological comparisons. There's no reason to expect that to happen if species aren't related.

RRoman · 08-17-2003, 06:32 PM

I always thought that dogs are among the better examples of evolution. But I think Charles Darwin should first tell us what he thinks evolution is.

Doubting Didymus · 08-17-2003, 06:33 PM

Oh yeah... and the widely accepted endosymbiont theory of chloroplast and mitochondria origin is independant evidence that all multicellular species were unicellular at some point in the past. You probably don't buy the aforementioned endosymbiont theory, but if it's not true, then the similarities between mitochondria and bacteria are slightly mysterious, as is the possession of said organelle of its own genetic material.

Charles Darwin · 08-17-2003, 07:40 PM

Quote:

Originally posted by RRoman
I always thought that dogs are among the better examples of evolution. But I think Charles Darwin should first tell us what he thinks evolution is.

The theory that the origin of the species can be explained as the result of natural forces and laws at work.

Charles Darwin · 08-17-2003, 07:41 PM

Quote:

Originally posted by Doubting Didymus
On the same note, the phylogenetic trees formed by standard genome comparisons confirm the trees built by morphological comparisons. There's no reason to expect that to happen if species aren't related.

I need a bit of help on this one. Why "no reason"? And what do you mean by related? For instance, why does a relationship prove evolution to be a fact?

Thread Tools	Search this Thread
Show Printable Version	Search this Thread: Advanced Search

08-17-2003, 05:12 PM	#24
Wounded King Veteran Member Join Date: Mar 2003 Location: Edinburgh Posts: 1,211	Are you saying that we don't observe microevolution? If so there are a couple of hundred pieces of primary literature I can refer you to. Why not tell us what you understand by evolution and then maybe we can tell you if it is a fact, you obviously don't like the definition Secular Pinoy gave. Where does the equivocation come in? In trying to dismiss the evidence as only microevolution. I personally think that evolution is a fact because of the various microevolutionary experiments that have been performed, the radical changes in morphology associated with highly specific mutations seen in developmental biology, the highly conserved nature of developmental programs and developmental signalling pathways, the fossil record, numerous studies on isolated population which have diversified and speciated (such as the cichlid fish in Lake Victoria) and a whole lot of other stuff that doesn't come to mind at the moment.

08-17-2003, 05:25 PM	#25
Doubting Didymus Veteran Member Join Date: Jul 2002 Location: East Coast. Australia. Posts: 5,455	Endogenous retroviral insertions confirming phylogenetic trees constructed on independant data prove that species descend from a common ancestor.

08-17-2003, 05:32 PM	#26
Doubting Didymus Veteran Member Join Date: Jul 2002 Location: East Coast. Australia. Posts: 5,455	On the same note, the phylogenetic trees formed by standard genome comparisons confirm the trees built by morphological comparisons. There's no reason to expect that to happen if species aren't related.

08-17-2003, 06:32 PM	#27
RRoman Regular Member Join Date: Apr 2003 Location: Durham, UK / Frankfurt, Germany Posts: 345	I always thought that dogs are among the better examples of evolution. But I think Charles Darwin should first tell us what he thinks evolution is.

08-17-2003, 06:33 PM	#28
Doubting Didymus Veteran Member Join Date: Jul 2002 Location: East Coast. Australia. Posts: 5,455	Oh yeah... and the widely accepted endosymbiont theory of chloroplast and mitochondria origin is independant evidence that all multicellular species were unicellular at some point in the past. You probably don't buy the aforementioned endosymbiont theory, but if it's not true, then the similarities between mitochondria and bacteria are slightly mysterious, as is the possession of said organelle of its own genetic material.

Freethought & Rationalism Archive

The archives are read only.