New research shows that elephants can differentiate between human languages, and act accordingly. Being able to distinguish different human languages may serve as an important survival technique for elephants, which have a long history of being hunted by humans.

"It is typically the case that different human subgroups pose radically different levels of danger to animals living around them," the authors write in a study recently published in the Proceedings of the National Academy of the Sciences.

The researchers used camouflaged speakers to play recordings of humans speaking in different languages to groups of free-ranging African elephants in Kenya. They also played the voices of people of different ages and genders, all saying "Look, look over there: a group of elephants is coming.” The researchers observed the elephants from a distance and recorded their actions on video.

When researchers played the voices of adult men speaking Maasai, a language spoken by a nomadic people known for traditionally hunting with spears, the elephants acted defensively. They pulled close together, protected calves and raised their trunks to smell for danger.

However, that was not the case for all human voices. When the elephants heard men speaking the language of the Kamba, a farming people who come into less frequent contact with elephants, the elephants were unperturbed. The elephants were also undisturbed by the voices of women and children.

The research was conducted over course of two years. Graeme Shannon, a behavioral ecologist at Colorado State University who co-led the study, told the L.A. Times that the experiments had to be spread out over time, so that the elephants wouldn't get used to the study.

It's important to note that the Maasai people should not be equated with ivory poachers. "The Maasai are a pastoral people who live around and interact with wild animals on a day-to-day basis in a way that most Western readers can probably not fully comprehend," writes Justin Boisvert for The Escapist. "Although they do spear and kill elephants on an individual basis, the Maasai should not be confused with larger scale commercial poachers, who indiscriminately slaughter entire herds of elephants using machine guns and grenades."