Painted Turtle (image) University of Cambridge Share Print E-Mail Caption The painted turtle, widespread across North America, is one of the turtle species that uses red pigment for external display as well as color vision. Samples from this species were used in the new study. Credit Nicole Valenzuela 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.