Black Rhino (IMAGE) American Institute of Biological Sciences Caption This photograph was created in the South African bush, by a public health field investigator, and depicts a young grazing black rhinoceros, a species studied using conservation endocrinology, with its two-horned snout, and leathery, wrinkled skin. Overall, the black rhino, Diceros bicornis, is classified as critically endangered, with three of the subspecies having been declared extinct in 2011, by the International Union for Conservation of Nature (IUCN). Credit CDC/ Jessie Blount Usage Restrictions None License Licensed content 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.