[Summary] Chickens outnumber all other species of birds by an order of magnitude and they are humanity's single largest source of animal protein. Yet for 2 centuries, biologists have struggled to explain how the chicken became the chicken. Now, the first extensive study of the bird's full genome concludes that people in northern Southeast Asia or southern China domesticated a colorful pheasant sometime after about 7500 B.C.E. People then carried the bird across Asia and on to every continent except Antarctica. The research team also found that the modern chicken's chief ancestor is a subspecies of red jungle fowl named...