Mouse Lemur Species Not Determined by Coat Color

Newswise — A team of researchers has found that nocturnal lemurs thought to belong to different species because of their strikingly different coat colors are not only genetically alike, but belong to the same species. The team, which includes Laurie R. Godfrey, professor of anthropology at the University of Massachusetts Amherst, and UMass graduate student Emilienne Rasoazanabary, has just published its findings in the open access journal BMC Evolutionary Biology.

Godfrey says the findings are significant because nocturnal species are often named on the basis of external coat characteristics.

The study was conducted on 70 mouse lemurs in Madagascar that were believed to belong to three different species. The team used analysis of a mitochondrial gene, cytochrome b, to test the genetic relationship of the lemurs on the basis of their coat colors.

The lemurs they tested had three different coat colors and lived in different types of forest locations in southern Madagascar — classic characteristics of separate nocturnal species. Surprisingly, the researchers found that although the lemurs appeared to be different species because they were visually distinct, they did not differ genetically. According to the sequence of this specific gene, all belong to the same previously identified species, Microcebus griseorufus.

The authors also show that lemurs with each of the three different coat colors could be found in all three geographical locations in similar proportions. They note that lemurs are nocturnal animals and tend to depend on auditory cues, or smell, more than on visual cues to recognize each other. They say that this could explain why a certain amount of variation in coat color does not affect species recognition in the mouse lemurs.

The other authors on the study are Kellie Heckman from Yale University, Anne D. Yoder at Duke University and Erica Machlin a former Yale undergraduate. The work was supported by a NSF-CAREER award Biodiversity Leadership Award from the Bay & Paul Foundations, grants from the Margot Marsh Biodiversity Foundation, Primate Conservation, Inc., the American Society of Primatologists, and the Wenner Gren Foundation for Anthropological Research.

Godfrey has spent three decades investigating fossils in Madagascar and has specialized in studying lemurs. Madagascar is a large island off the east coast of Africa, which is believed to have separated from the main continent millions of years ago. Because it was isolated, the island's animals have evolved on parallel tracks with those in Africa.

Godfrey has taught and conducted research at the university since 1977 and in 1998 received the university's Distinguished Teaching Award.