Weaning infants late led to woolly mammoth's end?

By studying the mammoth's teeth, researchers from the University of Western Ontario Earth determined that woolly mammoths in Old Crow, Yukon (Canada) didn't begin eating plants and other solid food before the age of two and perhaps three, according to a Western Ontario statement.

Sciences doctoral student Jessica Metcalfe, with professor Fred Longstaffe at Western Ontario, also consider predatory mammals like saber-toothed cats and a lack of sufficient vegetation to be the secondary reasons for delayed weaning, the Palaeogeography, Palaeoclimatology, Palaeoecology journal reports.

"In modern Africa, lions can hunt baby elephants but not adults. They can't kill adults. But they can kill babies and by and large, they tend to be successful when they hunt at night because they have adapted night vision," Metcalfe explains.

She examined fossil specimens alongside Grant Zazula of the Yukon Paleontology Programme. "In Old Crow, where you have long, long hours of darkness, the infants are going to be more vulnerable, so the mothers nursed longer to keep them close."Metcalfe says delayed weaning by Old Crow mammoths may have further significance for understanding mammoth life histories and extinction.

"Today, a leading cause of infant elephant deaths in Myanmar is insufficient maternal milk production," she adds.