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Re: Dollodon status questioned

Forwarded for Liz Freedman 

On Fri, Mar 25, 2011 at 1:36 AM, Jaime Headden <qi_leong@hotmail.com> wrote:

>   I wonder if McDonald uses some more substantive reasoning (optimistically, 
> I 
>assume he does) than in the abstract -- which is, let's face it, an abstract. 
>haven't the paper, but will soon.

Not really - he runs a PCA on a mere 3 measurements for each specimen
(which would give any statistician a heart attack), and those 3
measurements are all known to vary with the size of the specimen
(i.e., likely ontogenetically). Axis 1 (80% of variance) is probably
based entirely on the size of the specimen, with no real taxonomic

-Liz Freedman