Coconut Crab (image) University of California - Davis Share Print E-Mail Caption Coconut crabs show a color polymorphism, red and blue, the subject of current UC Davis research by Tim Caro and Vicky Morgan. Credit Tim Caro/UC Davis Usage Restrictions Provide credit. 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.