Male Mouse Lemur (image) University of Cambridge Share Print E-Mail Caption The testes of male mouse lemurs swell 5-10 times larger during the breeding season. Credit Cornelia Kraus Usage Restrictions Please 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.