Sperm Shapes (image) Field Museum Share Print E-Mail Caption Sperm from three closely related species of vesper mice. While these mice look very similar and can be hard to tell apart with DNA, their sperm shapes are radically different. Credit Luis Rossi, Noé de la Sancha, et al. Usage Restrictions Please include 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.