Dog Coat Patterns Have Ancient Origin (IMAGE) University of California - Davis Caption Jiff the collie represents 'shaded yellow,' one of five coat color patterns in domestic dogs identified by Danika Bannasch at the UC Davis School of Medicine and collaborators in the U.S. and Switzerland. The genes for these coat types originated about two million years ago in an extinct relative of dogs and wolves. Credit Susan Larson Usage Restrictions May be used with acknowledgement. License Original 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.