"But What About The..." arguments Re: dinosaur-centred extinction models

["David Elliott" <dalelemu@hotmail.com>]

David Marjanovic wrote:

> The problem here is, IMNSHO, that you try to explain the extinction of the 
> dinosaurs. Yeah, right. :-) Why did the ammonites die out? The rudists and 
> the inoceramids? Heaps of foraminifera and haptophytes*?

I'm not sure that's a valid counter-argument: it assumes that the original 
poster is claiming that their idea explains the extinction of mosasaurs, 
rudists, etc etc - as far as i recall he only claimed to be explaining the 
extinction of the dinosaurs.

Sure it may wall be a good assumption that they're linked, but it's an 
assumption nonetheless - wouldn't the proper counter-argument be to argue 
that they're linked, so you can *then* say "what about the foraminifera and 
so forth", or "your theory doesn't account for the link"?

But even then, in science don't we usually figure out small parts of things 
before we put them into a larger framework? Don't we often see parts of the 
puzzle before we see the larger picture? I don't see how not having a larger 
model to explain ALL the extinctions invalidates a smaller idea about one 
groups extinction specifically.

And Steve Brusette added:

> 1) As David mentioned, even if dinosaurs did spread diseases between one 
> another, this does not explain the extinction of mosasaurs, rudists, 
> ammonites, forams, etc.  I once asked Bakker about this in an interview and 
> he didn't have anything to counter the argument.

Regarding Robert Bakker, he DID actually talk about the extinction of all 
those other critters (in TDH), although in my lurking i've noticed that his 
extinction-model seems to have been inadvertently edited (in this particular 
conversation), unwittingly creating the impression that he didn't: His idea 
wasn't just "diseases spreading to places they haven't been before", which 
is kind of the impression you get from recent comments - that was one part 
intrinsically tied in with a larger model. And it's the larger model that 
accounted for the extinction of those that (we're assuming) went along with 
the dinosaurs. (unless, of course, he has since withdrawn everything about 
his model except for the dinosaur-disease bits) (pages 440-444 The Dinosaur 
Heresies)

Bringing it back to the point Steve was making in that particular paragraph 
(and btw, yes, i know you gave other reasons against Bakker's model, it's 
just this one im objecting to).

Say for a moment that Bakker didn't have a larger model worked out to 
explain everything else's extinction. Even then, the "what about the..." 
argument wouldn't apply as a counter-argument. It would be a call for some 
larger integrated model, or for some argument about wether or not the 
dinosaurs extinction *is* related to the foraminifera etc etc extinctions, 
but i don't think it invalidates the virus-idea in any way.

To a vaguely related topic that i just thought i'd raise while i was here - 
how strongly linked are the extinctions of mosasaurs, foraminifera, 
plesiosaurs, etc etc..?

Have statistical studies been done into the probability of 'everyday' rounds 
of extinctions occurring, by chance, during other larger extinctions to 
create the impression that they're related when they're not (and how sure 
are we of timing, btw? It seems to me the chance of this is increased when 
you consider that we can't always tell *exactly* when something 
dissappeared)? Im just thinking, if stegosaurs had happened to delay their 
extinction until the end of the Cretaceous, we'd assume they were part of a 
mass extinction that they might not have been. Are mosasaurs, for example, 
such a large and diverse group (i don't get the impression that they are) 
that their extinction is statistically something drastically different from 
the extinction of a group like the stegosaurs?

How regular are extinctions of groups of sizes comparable to the various 
components of the K-T extinction? Im not saying no mass extinction occured, 
i'm really just asking, how sure are we that EVERYTHING that died out at 
that time is a part of the one big thing?

Is it possible that, say 5-15% (just pulling a figure out of my sleeve for 
the sake of argument, theres no meaning in those numbers) of some mass 
extinctions are just coincidence - actually, isn't it almost *certain*?

How much of the synchronicity of the extinctions of various groups is likely 
due to regular "background" extinctions occuring at the same time, and how 
much is due to a common cause? It strikes me that we *should* expect times 
when some groups happen to go out for unrelated reasons at the same time. 
(And, maybe because we're biased towards seeing patterns, it CAN be shocking 
sometimes to see something that we thought was an obvious pattern turn out, 
when you run statistical analyses, to be not as strong as it looked. Once 
again, im not saying this'd mean there wasnt a mass extinction event of some 
kind, just that it might not have involved everyone we thought it did (Or 
maybe there were even a couple of mass extinctions simultaneous but with 
different causes?). And if it didn't, if some groups might've gone for 
unrelated reasons, then an argument like the virus-argument - i.e. about the 
extinction of one *particular* group - is quite perfectly valid and 
expected, and the "What about the foraminifera etc..." argument has an extra 
point against it.)

Anyone know of some good papers/work having been done around this issue? (It 
seems like the kind of thing there'd be heaps written about, or maybe i've 
just been studying too hard for my ecology exam and have t-tests and the 
like 'on the brain')

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