How Lions Became Social

August 6, 2015
Five female lions walk as a group on grassy ground, lit by a low sun.

Why do lions live together in prides, when leopards, cheetahs, tigers, and the neighborhood tabbies don’t? 

Led by then-graduate student Anna Mosser, a team of behavioral ecologists-cum-detectives looked at the evidence piece by piece, focusing on female lions, who form the basis of any pride.

Several hypotheses were initial suspects:

• Banding together improved hunting success

• Groups formed to defend cubs

• Groups could better defend their territories

After internationally renowned lion researcher Craig Packer and colleagues had eliminated the first two hypotheses, Mosser led a study of the third, using simulations to see whether the character of the African savanna where the lions lived could make solitary animals become social. Sure enough, the African savanna landscape, plus lions’ ability to band together to defend their piece of it, emerged as strong shapers of lion sociality.

The full story tells how the researchers deduced the long-sought answer, and its postscript points the reader to Packer’s new book detailing his decades of work with lions—and the issues surrounding hunting and other lion-human contact.