Elephants recognise human voices

http://www.bbc.com/news/science-environment-26488432

Elephants are able to differentiate between ethnicities and genders, and can tell an adult from a child - all from the sound of a human voice.

This is according to a study in which researchers played voice recordings to wild African elephants.

The animals showed more fear when they heard the voices of adult Masai men.

Livestock-herding Masai people do come into conflict with elephants, and this suggests that animals have adapted to specifically listen for and avoid them.