check this paper by Ávila-Arcos et al:

http://www.nature.com/srep/2011/110824/srep00074/full/srep00074.html?WT.ec_id=SREP-20110830

I can only offer some general remarks: The main question might be whether there is any established or suitable marker system that allows you to trace back the origin of different types of maize in modern samples. And depending on this marker system you should outline your strategy for sequencing (Saenger or NGS). Of course the age of the samples is also of importance.

I recommend you to check the thesis of Claudia Grimaldo "Investigating the Evolutionary History of Maize in South America" available online:

https://www.escholar.manchester.ac.uk/api/datastream?publicationPid=uk-ac-man-scw:156900&datastreamId=FULL-TEXT.PDF. I can put you in contact with her if you need it as she is good friend of mine.

Hope it helps.

Check with Rafael Montiel (Rafael Montiel ). His entire institute deals with this. Another person interested in the coprolite microbiome as it relates to diet is Raul Cano. You can find him on the web.

Chuck Greenblatt

Mario Aliphat from Colegio de Postgraduados in Mexico.

Mario is been working in this topic for several years, he is graduated from Calgary, University. Alberta, Canada.

Thanks Daniel for pointing out the Ávila-Arcos paper. More publications with maize aDNA should be coming the in future, but check out our blurb here: http://geogenetics.ku.dk/research_groups/gilbert_groups/maize/

I have been doing isoenzyme gels on native grass seeds though HyPure, extracting the seed proteins and running the gels with the esterase enzyme, and getting good banding patterns from 100+ year old seeds from herbarium specimens.

Thanks to everyone for their very helpful input. It seems that much of the work is looking at genetic diversity as a way to reconstruct evolutionary history, while I'm curious about the potential of genetic diversity to measure the range of maize sources at any given moment in time. I'll need to spend some time reading up on this, so thanks for the sources and contacts.

Thanks Michelle. I know Benson's work well. The problem with Sr isotopes is that there's arguably too much overlap in the geological sources, and therefore isotopic diversity is hard to interpret. I was thinking of maize aDNA as a possible alternative, although I can see it'd have analogous issues. Has there been work looking at geographically constrained haplotypes in the SW?

Hi, I am starting a thesis on similar a similar subjetc, trying to compare variabilities between archaeological maize samples, dated between 0-1000 AD. These samples come from hyperarid location in northern part of Chile, so I am also cheking if DNA sequences (microsatellites ) can say anything about variability. According to my sources we should find ADN diversity, but it all depends on the high rate mutation and how sensitive is nDNA maize to human manipulation.