Much more from the chicken's egg than breakfast--a wonderful model system.

The chick embryo has played a major role in the advance of our understanding of embryonic development. It has been particularly helpful in relation to amniotes like the mouse, for unlike the mouse in the early embryo the epiblast is beautifully flat, while in the mouse it is all curled up. Here I briefly describe some history and a few of the major achievements that came from the chick embryo.