how can i devolp an thesis statement for an dbq essay comaring modern mongolians and their ancestors.

First you have to do the research. Make a list of the differences and similarities between the modern and ancient Mongolians.

Then study these sites for advice in developing a thesis statement.

http://www.unc.edu/depts/wcweb/handouts/thesis.html

http://owl.english.purdue.edu/owl/resource/545/01/

http://www.indiana.edu/~wts/pamphlets/thesis_statement.shtml