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Re: K-T Theories

 From: rking@flir.com ("Randy King, go player and all-around swell guy!")
 > I went to Dr. Bakker's lecture last Friday here in Portland, Or.  He promotes
 > the disease theory of the K-T boundary.  ...

Neither do I.

 >  My problem with the theory is two-fold.  First, there is the
 > issue of spreading the disease.  There are three continental islands where 
 > the
 > die-off is, presumable, simultaneous with the rest of the land masses, namely
 > Australia, India, and Antartica.  How is the simultaneaty of the die-off
 > believed to have occurred.

Well, to start with, the die off is not necessarily simultaneous in
the sense you are thinking of.  A span of 50,000 years would be
indetectable in the fossil record.  Also, except where the iridium
anomoly is present, correlations between widely seperated continental
deposits is not accurate to even *that* level (more like 100,000+
years variance).  This means that the die-off could have taken as
much as, oh, 150,000 years with almost no way of finding out.

This is a *long* time, as far as individuals are concerned.
 > The second part is the vastness of Dinosauria.  I don't recall whether this
 > is a sub-class or a super-order, or what.  The point is that there are many
 > different species of dinosaur alive.  It would be hard to imagine a disease
 > that affects all mammals, even less so given that it would be fatal and 
 > spread
 > rapidly across the world (without jet travel! :-) ).

Dr. Bakker is not that naive.  He is proposing a *pattern* of
*multiple* diseases spreading around the world due to elmination
of the main barriers to spread.

In short what he is talking about is smoething like what happened
the the American Indians after Europeans arrived - numerous new
diseases for which they had low resistance compared to the Europeans.

Now, if this happened to go both ways, and in multiple species ...
 > I have a second question - easier...
 > What is the plural of archaeopterix?

Well, the singular is Archaeopteryx.
A semi-classical plural would be Archaeopteryces.
A pure English plural would be Archaeopteryxes.

swf@elsegundoca.attgis.com              sarima@netcom.com

The peace of God be with you.