Atmospheric O2 Levels and Dinosaur Growth

["Kay A Ferrari" <Kay.A.Ferrari@jpl.nasa.gov>]

Dear Dinosaur Experts,

A while ago I had a conversation with Adriana Ocampo and her husband Kevin 
Pope, who are geologists studying the Chixulub crater region for the Jet 
Propulsion Laboratory.  During the conversation, they mentioned that oxygen 
levels in the Mesozoic atmosphere fluctuated significantly, sometimes getting 
up as high as 35 percent.  This information, Kevin said, was gathered by 
analyzing air pockets in amber from different time periods.  Although, he was 
quick to state, the information was far from complete.

The discussion caused me to wonder if the higher levels of oxygen in the 
atmosphere could be a contributing factor to an increase in the size of certain 
dinosaurs.  Although Adriana lent me her notebook of reference materials, I 
found few references that indicated the Mesozoic time periods when oxygen 
levels were higher and no references to comparisons of increased oxygen levels 
and dinosaur growth.

I would appreciate any comments on these questions, and/or information about 
publications that address these subjects.  If these speculations are totally 
off the wall, I would appreciate knowing this, too.

Thanks in advance.

Kay Ferrari
Public Services Office
Jet Propulsion Laboratory
4800 Oak Grove Drive, MS 186-113
Pasadena, California 91109
Phone:  818 354-9314
Fax:  818 393-4641
Kay.A.Ferrari@jpl.nasa.gov