How male mammoths died in ‘silly’ ways
Swallowed by a sinkhole. Washed away by a mudflow. Drowned after falling through thin ice.
These are the fates that many unlucky mammoths suffered in Siberia thousands of years ago. Their wellpreserved fossils have provided paleobiologists with insight into their prehistoric lives. Now, after performing a genetic analysis on the remains from the furry victims of natural traps, a team of scientists made a striking discovery: Most were male.
“In many species, males tend to do somewhat stupid things that end up getting them killed in silly ways, and it appears that may have been true for mammoths also,” said Love Dalén, an evolutionary biologist from the Swedish Museum of Natural History.
In a study published last Thursday in the journal Current Biology, Dalén and his colleagues analysed DNA from nearly 100 mammoth bones, teeth and tusks, and found that about two-thirds came from males. They speculate the reason for the skewed sex-ratio may have to do with the risky behaviour that young males exhibit after leaving the protection of their mothers to live on their own.
The finding was an accident, said Patrícia Pečnerová, a doctoral student at Stockholm University and lead author on the study. It came while she was entering data for a different project on mammoth genetics. “While filling this in on the spreadsheet, we were really surprised to see there were more than twice as many males as females because there was no previous research or indication that that should be the case.”
The 98 specimens that the team analysed came from the north of Siberia and had been collected over the course of four decades. They found that 66 were male and 29 were female. The oldest were more than 60,000 years old, and the youngest, a specimen known as “Lonely Boy,” was about 4,000 years old. The data did not provide insight into how old the mammoths were when they died, only their sex.
The thought is that mammoths, like today’s elephants, lived in matriarchal societies where adult females protected the young. But around the ages of 14 or 15 when puberty set in, males left their herd and either became loners or joined bachelor groups, which were often led by inexperienced males. That was when they were more likely to do something risky, and find themselves stuck in frozen muck. The natural traps buried their bodies quickly, protecting them from scavengers.