November 30, 2004

WELL, WE'VE ALL RULED OUT ONE THEORY:

How the Big Freeze Killed the Buffalo (William Underhill, 12/06/04, Newsweek International)

Picture a bison. He's curly-headed, low-slung and huge. The male, the largest land animal in North America, may stand two meters high and tip the scales at one ton. Despite this formidable profile, the bison was no match for humans. In the 19th century, hunters brought ecocataclysm to the Great Plains, slashing bison numbers from around 60 million to fewer than 1,000.

Maybe Nature should share the guilt. Scientists now say that the earliest bison population in North America fell victim to a more contemporary scourge: climate change. Alan Cooper, a molecular evolutionist at Oxford University, blames a big freeze, not man, for driving the species to near extinction in prehistory.


At least we've reached this point in our discussions of Evolution: some may think Man (intelligent intervention) caused the extinctions and some may think it was a catastrophic punctuating event (most likely triggered by events from without the biosphere), but no one any longer thinks it was a long natural process of tiny changes.

Posted by Orrin Judd at November 30, 2004 3:13 PM
Comments

You are mis-applying the basic principles of Darwinism. Which may be at the heart of why you are so convinced that it is wrong, come to think of it.

For one thing, extinction events and evolution are two different, albeit related, things. For another, there may be small changes occurring in the bison population right now (there really hasn't been that much time that has passed from a geologic and evolutionary perspective), but these changes will not accumulate to a "speciation event" until thousands or hundreds of thousands of years from now.

And finally, let's just say that a hugely successful bison mutation occurred tomorrow in a small group that you didn't have under direct observation. Or, more accurately, that small changes began 100,000 years ago and have just now gotten to the point of not looking like bison any more. When you eventually come across this group, what would you see? Another static population showing no signs of evolving.

Posted by: HT at November 30, 2004 3:56 PM

HT:

So speciation takes longer than the catastrophic events that cause mass extinctions, right?

Posted by: oj at November 30, 2004 4:10 PM

Well, yes. But I do not think that means what you think it means (to paraphrase Inigo Montoya).

Not all evolution stems from extinction events, for example. An extinction event may in fact change the dynamics between competing populations, opening up ecological niches into which genera will "move". But slow changes can create the same sort of opportunity.

But it seems as if you had a point that you wanted to make after determining what I thought about your specific question, yes?

Posted by: HT at November 30, 2004 4:18 PM

Just curious...you've got these species that are stable for hundreds of thousands of years, longer in fact than they actually exist?

Posted by: oj at November 30, 2004 4:26 PM

OJ/HT -

You may want to peruse this fine essay by the combative Phillip Johnson, who discusses just this topic:

http://www.arn.org/docs/johnson/raup.htm

The short version is that Johnson agrees with OJ. Johnson's essay originally appeared in the February 1992 edition of The Atlantic magazine. It led to 3 consecutive issues of letters to the editor...and David Raup wrote Johnson privately to say that he (Raup) agreed with Johnson's reasoning!

Posted by: Bruce Cleaver at November 30, 2004 4:35 PM

Bruce:

That's perfect! There's not much left of Darwinism if you're as honest as HT or Raup.

Posted by: oj at November 30, 2004 4:51 PM

Also, don't neglect the hand of Man in getting the number up to 60 million in the first place. Fire was used as a tool to keep the plains clear of brush and timber and provide ideal rangeland for bison and other large grazers like elk.

Posted by: Raoul Ortega at November 30, 2004 5:27 PM

Raoul:

Lewis and Clark, coming from heavily forested Virginia and the Ohio River Valley, were astonished at the tree-less plains of the Missouri River region. They then discovered the cause: the Indians burned the grasslands every autumn to kill tree saplings.

Posted by: Fred Jacobsen (San Fran) at November 30, 2004 6:45 PM

OJ: I am baffled by your most recent comment. Why are you drawing the conclusion that something about evolution requires that species must be stable for "longer...than they actually exist?"

I will also go read that article as suggested by Bruce, just to get an additional insight into what you are talking about. But direct clarification would still be greatly appreciated.

Posted by: HT at November 30, 2004 7:53 PM

you

"changes will not accumulate to a "speciation event" until thousands or hundreds of thousands of years from now"

Posted by: oj at November 30, 2004 7:59 PM

A couple of books on the subject--
Shepard Krech, The Ecological Indian
Stephen Pyne, Fire in America

Posted by: Raoul Ortega at November 30, 2004 8:10 PM

All parcels of the Earth's surface have moved through all the Earth's climatic zones.

Since that movement is so slow as to be nearly imperceptible, those changes cannot have been "catastrophic."

But since virtually all animals prior to man are climate-specific, how is it there is life anywhere on land?

Posted by: Jeff Guinn at November 30, 2004 9:45 PM

Orrin is being coy again.

He very knows of, even if he remains unwilling to acknowledge, the role of 'founder events' in speciation theory.

He dare not engage with the theory as actually presented by the theorizers.

Posted by: Harry Eagar at November 30, 2004 10:09 PM

Harry:

You present the theory and I'll gladly poke the holes.

Posted by: oj at November 30, 2004 11:26 PM

Jeff:

Because climate has so little influence unless it changes drastically and suddenly.

Posted by: oj at November 30, 2004 11:33 PM

To begin with, speciation has nothing to do with the pace of extinction, or the longevity of what are called chronospecies.

For speciation to occur, a 'founder event' is needed. It need not be associated with an extinction.

Posted by: Harry Eagar at December 1, 2004 1:56 AM

Ah, so the argument you offer to prove speciation is that a speciation event must occur? Not circular at all, is it?

Posted by: oj at December 1, 2004 8:42 AM

Speciation events and climate-caused extinctions are elements of darwinist explanations of evolution.

Pointing them out doesn't score points against darwinism.

It might score points against Orrin's strawman 'darwinism' (which takes the hard line that incremental changes alone produce speciation and evolution).

But nobody argues for that version of darwinism, no matter how hard OJ argues against it.

Posted by: Brit at December 1, 2004 9:48 AM

Brit:

Yes, the problem is not that Darwinism argues that "incremental changes alone produce speciation and evolution", that's so obviously disproved that no sensible person would maintain it, but that, so far as we can tell, only Man and catastrophic climate change cause extinctions.

Posted by: oj at December 1, 2004 10:22 AM

So far as we can tell, man and climate changes can cause extinction. Don't be in such a hurry to conclude that therefore nothing else can.

Posted by: Brit at December 1, 2004 11:45 AM

There's no rush--y'all have been amusingly wrong for two hundred years, another few hundred thousand can't hurt.

Posted by: oj at December 1, 2004 12:01 PM

1) Anybody ever heard of "Punctuated Equilibrium"?

2) Anybody ever figured (with the incompatible "Die, Heretic!" explanations for mass extinctions) that what really happened might have been a combination of causes and effects occasionally coming together in a perfect storm situation?

Posted by: Ken at December 1, 2004 12:52 PM

"Because climate has so little influence unless it changes drastically and suddenly.

Plate tectonics means all parcels of land have experience climate change both drastic and slow.

So, OJ, unless terrestrial life adapted somehow, how could there be any?

Of course, there are other causes. The emergence of the Panama isthmus was neither sudden, nor catastrophic. However, once it separated the Caribbean from the Pacific, life on both sides diverged. And many, if not most, of the species left on the Caribbean side eventually became extinct.

Long before man. No meteors involved. Oh, and there are clear instances of chronospecies.

Posted by: Jeff Guinn at December 1, 2004 7:15 PM

Yes, that's the question isn't it.

Posted by: oj at December 1, 2004 7:39 PM

The question is why you say that only man or catastrophe can result in extinctions.

How about the Franklin tree?

Posted by: Harry Eagar at December 1, 2004 8:25 PM

Yeah, who ever heard of men cutting down trees.

Posted by: oj at December 1, 2004 8:36 PM

You don't know the story, do you?

Posted by: Harry Eagar at December 2, 2004 2:29 PM

I've read Bartram, I don't know why you think the franklin trees matter--they prove my point.

Posted by: oj at December 2, 2004 2:43 PM

"So, OJ, unless terrestrial life adapted somehow, how could there be any?"

Posted by: Jeff Guinn at December 2, 2004 8:19 PM

Jeff:

Life was Created (even you Darwinists acknowledge your theory is useless for the most important question it should explain--the rise of life forms in the first place). It adapts. It does not evolve via Darwinism but via some kind of punctuating interventions so far as we can tell. That's why orthodox Darwinists hated Stephen Jay Gould so much.

Posted by: oj at December 2, 2004 8:23 PM
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