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Re: paleontolgist, dinosaur



On Thu, 7 Nov 1996, Stan Friesen wrote:

> > 1. What is your theory about how the dinosaurs got extinct?
> 
> A combination of causes occuring in a geologically short time period
> combined to drive them to extinctions.  Some of the main contributors
> were:
>       1. The volcanic eruptions forming the Deccan Traps in India.
>       2. The lowering of sea levels to nearly as low as they now are.
>       3. The impact of a giant meteorite, perhaps in the Yucatan
>       4. Possibly (little evidence available as yet), an large
>          decrease in the oxygen content of the oceans (oceanic anoxia). 

These are events, not causes.  How did they drive all dinos (big and 
small) to extinction  while leaving many other terrestrial lineages 
unaffected.  Archibald's Montana data shows the following % species 
survivorship:
Placentals - 100%
Marsupials - < 10%
Lizards - > 25%
Turtles - > 80%
Crocs - > 75%
Champosaurs - 100%
and, of course, non-avian dinosaurs, 0%

How did your events, real though they may be, affect the other reality 
reflected in the available fossil evidence?