Diagram of Taxonomy, Development, and Beak Shape (image) Harvard University Share Print E-Mail Caption A comparison of beak developmental programs and eventual beak shapes reveals a high degree of flexibility in their relationship. Darwin's finches (Geospiza, bottom left) and the Lesser Antillean Bullfinch ("small bullfinch") employ similar cell populations and genes to establish very distinct beak shapes, while the larger species of Caribbean bullfinches use a novel combination of two signaling molecules to build a beak identical in shape to the smaller bullfinch. Credit Image courtesy of Ricardo Mallarino Usage Restrictions None Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.