Greater Antillean Bullfinch (image) Harvard University Share Print E-Mail Caption Greater Antillean bullfinches (Loxigilla violacea) use their deep and wide beaks to crush seeds and hard fruits. Harvard researchers have found that the molecular signals that produce a range of beak shapes in birds show even more variation than is apparent on the surface. Credit Photo by José M. Pantaleón 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.