This was pretty much irresistable - a pair of papers in today's Science about the evolution of maize, from the wild teosinte to the grain we know and love today:
Call it "the tortilla gene." It is a little piece of corn DNA that may have improved the way corn starch sticks together.If scientists' hypothesis about it is correct, it would have allowed early Americans thousands of years ago to mash up corn kernels to make the first tortillas.
With a handful of similarly useful changes, early Americans turned a wild Mexican grass called teosinte into the highest yielding grain crop in the world and changed human culture on this continent.Nurtured by early Native American farmers, the genes turned the bushy teosinte grass into the cornstalks we know today, and the rock-hard teosinte seeds into the tender kernels that grace modern cobs.