Topi bucks frighten potential mates into staying near by pretending there is a threatening lion.

Scientists studying topi bucks observed them snorting and looking intently ahead when an available female began to stray from their territory.

The behaviour suggests there is a dangerous predator ahead, such as a lion or cheetah.

But the male topi's signals were false ones designed to fool the female into staying close by.

Keeping the frightened female secure in his territory increases the male's chances of mating.