Hi- Archaeologists have been using the differences in carbon isotopes of
human bone collagen to trace the spread of corn agriculture across N.
America for decades. It may be an interesting way to introduce the use of
corn and its influence on lifestyle/culture to your colleague's audience.
A classic study is:

1978 N.J. van der Merwe & J.C. Vogel. 13C content of human collagen as a
measure of prehistoric diet in Woodland North America. Nature 276:815-6.


>
> Hi Again,
>
> I forgot to mention - and you probably know this anyway, but corn
> (maize) is a C4 plant unlike most vegetables which are C3 plants -
> the C4 pathway produces a distinctive carbon isotope signature that
> is different from that of C3 plants so that animals that live mostly
> off of C4 plants can be easily identified.  So the isotopic evidence
> would be in papers referring to C4 pathways.
>
> Lola.
>
>
>
>
>
> .
>
>
>
>
> At 12:58 PM 1/22/2009, you wrote:
>>Dear Folks,
>>
>>I received this message from a colleague who is teaching students
>>about the influence of corn. Do any of you alert readers have a
>>reference at your fingertips that you could recommend for Charlie?
>>
>>"Next Tuesday Washington College is hosting a viewing of the movie "King
>>Corn," which is a critique of the use of corn products in our country
>> (see
>>description below).
>>
>>One of the most fascinating things I heard about this issue was in one of
>>your talks: The stable isotope evidence that Europeans coming to the US
>>experience a shift in their carbon isotope ratios in response to the
>>corn-heavy diet.  Does that data appear in publication anywhere? I would
>>love to bring that up at the viewing of this movie during the discussion
>>period."
>>
>>Marilyn Fogel
>>
>>
>>Dr. Marilyn L. Fogel
>>
>>Geophysical Laboratory
>>
>>Carnegie Institution of Washington
>>
>>5251 Broad Branch Rd., NW
>>
>>Washington, DC 20015
>>
>>Phone (202) 478-8981
>>
>>Main office (202) 478-8900
>>
>>FAX (202) 478-8901
>>
>>Website: <http://fogel.gl.ciw.edu/>http://fogel.gl.ciw.edu/
>