Many elephants at the Gorongosa National Park in Mozambique, Africa, are lacking one distinguishable feature that elephants usually have: tusks. Researchers believe the heavy presence of poaching has led elephants here to evolve without tusks, so their human predators have no reason to kill them and steal their tusks for ivory.

“There’s multiple things that could produce that sort of thing in elephant populations, but the leading hypothesis … is that there’s been a substantial amount of pressure placed on those populations by poachers,” Long told CBS News.

Long, an assistant professor of wildlife sciences University of Idaho, said tusks are usually a necessity, especially for male elephants. Males use their tusks for combat and for breeding rights, among other things. However, in an environment where poachers are a mortal threat, “tusks suddenly become a liability,” Long explained. “And […]