LIFE has a photo gallery of Brent Stirton's photos of tribal groups in Ethiopia's Omo River Valley.
Brent Stirton is a senior staff photographer for Getty Images and a LIFE.com contributor who routinely spends nine months of the year on assignment, all over the world, covering everything from narco-wars in Afghanistan to "fog harvesting" in Nepal. In 2007, Stirton spent two weeks in Ethiopia's Omo River Valley, documenting tribal groups that still live largely as they have for centuries. "This is a woman of the Mursi tribe, wearing boar's tusks, which traditionally would be considered men's decoration. The Mursi women are famous for their clay lip plates, a symbol of beauty. A woman would literally have a little hand bag with three or four of them featuring different designs. Sort of their own version of Prada."