Quetzal

Camaban:

No, you probably read it correctly. I would personally have just challenged the assertion about kangaroos, etc in North America.

Actually, it appears that marsupials originally evolved (during the Cretaceous - ex: Peradectes) in North America, then radiated everywhere else, including what became Antarctica, during the Paleocene. By the start of the Oligocene (37 mya) the last North American marsupial was extinct - and they never resembled anything like the modern fauna in Australia. Modern NA marsupials like the opossum (Didelphus) are immigrants from South America when the Panama land bridge re-opened.

I didn't mean to detract from your post. Like I said, I'm merely an evil pedant who thinks if we're gonna bash creationists on their abysmal science, we'd better have OURS right. No offense intended and no apology necessary.

Returning you now to your regularly scheduled rant.

[Edited to add: <a href="http://www.paleocene-mammals.de/marsupials.htm" target="_blank">Here's</a> a good link on marsupial evolution and radiation for those interested. Enjoy.]

[ June 10, 2002: Message edited by: Morpho ]</p>

Oolon Colluphid

Erm, there�s hundreds of blind and near-blind species with eye remnants: salamanders, fish, insects, marsupial moles, naked mole rats... to name a few.

Ye-esss... your point?

So, uh, if a salamander or mole rat has things recognisable as eyes, but which cannot function as eyes, it�s natural selection at work, they weren�t created like that, yeah?

You are saying that if something has the correct morphology -- ie it is in the right place and made from the right components -- then even if these components are reduced, and/or some of them are absent (eg the marsupial mole�s lens and retina), it was indeed formerly a functioning eye, and it has �devolved� by natural selection. Am I right so far?

What then do you make of the guinea pig�s tail, which doesn�t extend outside its body? Made that way, or �devolution� from a tailed ancestor?



And what then do you make of the human coccyx (see my post to you in <a href="http://iidb.org/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=58&t=000889" target="_blank">this thread</a>? Made that way, or �devolution� from a tailed ancestor? And how do you know which?

What about the sort of devolution by natural selection that reduced the toes on horses� feet?

What of the sort of devolution that gave birds only a tiny splint for a fibula... yet left them with inoperative genes which, when reactivated by simple surgery, make a full fibula?

<a href="http://www.mun.ca/biology/scarr/Hampe_experiment.htm" target="_blank">www.mun.ca/biology/scarr/Hampe_experiment.htm</a>



Or the <a href="http://www.devbio.com/chap06/link0601.shtml" target="_blank">inoperative genes birds have for making teeth</a>?

But if things can reduce gradually, they can also gradually lengthen or increase. How about the sort of devolution by natural selection that could lengthen a pentadactyl limb�s digits into something like this:



You have one thing right: nature builds on what has gone before. But it is not �devolution�. It is simply evolution.

TTFN, Oolon

Baidarka

Mad Mike:

Please try to answer the first 3 questions.
I'll respond in more detail when I get a chance.

Oolon Colluphid:

The bat Xray is really incredible

Duvenoy

I'm curious here (never heard of any marsupials outside Australia) Wouldn't have any sources, would you?

The Viginia Opossum is a very common marsupial found mostly in the Southeast US.

References: Every highway in North Carolina.



d

RufusAtticus

Last one I hit got suck under my car and was there for a few days.

Interesting fact: the scientific name for opossums means "the (thing) from virginia with two wombs."

~~RvFvS~~

wildernesse

The scientific name for the Virginia Opossum is Didelphis virginianus. Here is a link about them: <a href="http://www.cfr.msstate.edu/predator/opossum.html" target="_blank">possums</a>

--tiba