The great lemur mystery

Natural History, Feb, 2002 by Kirsten L. Weir

One of the biggest puzzles in primate evolution is how and when lemurs first arrived on the island of Madagascar, the only place they're found today. Though ancient remains of their close relatives, the lorises, have been found throughout Africa and Asia, fossil evidence for lemurs hasn't extended beyond Madagascar--until now.

Digging in Pakistan's Bugti Hills, Laurent Marivaux, of the Universite Montpellier II in France, and colleagues discovered the remains of a 30-million-year-old lemur, the oldest such fossil ever unearthed. The researchers believe that the creature, named Bugtilemur mathesoni, was most closely related to the modern genus Cheirogaleus (dwarf lemurs) and was similar in size to today's hairy-eared dwarf lemur, which weighs in at about three ounces.

Till now, scientists thought the common ancestor of lemurs and lorises was a native of Africa, but the discovery in Pakistan suggests alternative scenarios. According to the team that found the fossil, Bugtilemur and Cheirogaleus share enough features to preclude their divergence from a common ancestor before Madagascar broke away from India 88 million years ago. Instead, lemurs may have migrated later on a route between the drifting landmasses. But which direction were they headed?

Bugtilemur's ancestor could have migrated from Africa to Madagascar and then toward Pakistan. But it may be just as reasonable to suggest that the group originated in Asia. Whatever the timing and direction of the migrations, the researchers agree that South Asia was "an important theater" of early lemur evolution. ("A Fossil Lemur From the Oligocene of Pakistan," Science 294, 2001)