[attach id=319036 size="medium"]An Indian elephant calf in its enclosure at Twycross Zoo, Warwickshire, the UK. Photo: Tim Goode/PA Wire[/attach]

The big ears are not just for show.

Elephants can tell whether a human poses a threat by listening to his voice and sussing out subtle clues about his age, gender and ethnicity, according to a study.

Researchers from the University of Sussex and the Amboseli Trust for Elephants played recordings of human voices to wild elephants in Kenya and watched how they reacted.

“Our results demonstrate that elephants can reliably discriminate between two different ethnic groups that differ in the level of threat they represent,” the authors said in an article published in the Proceedings of the National Academy of Sciences.

The study said an elephant herd was more likely to bunch up in a defensive position following playbacks of voices of Maasai people, an East African ethnic group that has hunted elephants for centuries, than other groups.

“Moreover, these responses were specific to the sex and age of Maasai presented, with the voices of Maasai women and boys, subcategories that would generally pose little threat, significantly less likely to produce these behavioural responses,” according to the study.

Other animals seeking to avoid hunters may also have developed this skill

The researchers said the findings provided the first proof elephants can distinguish between human voices, and suggested that other animals seeking to avoid hunters may also have developed this skill.

“Considering the long history and often pervasive predatory threat associated with humans across the globe, it is likely (this ability) could have been selected for in other cognitively advanced animal species,” it said.