Cheetah chasing impala

Impalas are fast but cheetahs are faster. Credit: Anup Shah/Minden Pictures/Getty

Animal behaviour

An evolutionary arms race on the savannah

Nimble prey slip away during slow chases.

Mighty muscles and phenomenal speed should give powerful predators the edge. But scientists have learned that prey animals have their own winning strategy: the last-minute dodge.

Predators and prey are engaged in a constant evolutionary arms race, each striving to be faster and more nimble than the other. To investigate the animals’ interactions, Alan Wilson at the Royal Veterinary College in Hatfield, UK, and his colleagues studied lions in pursuit of zebras, and cheetahs chasing down impalas, on the savannah in Botswana.

The team found that each predator had 20% more muscle power than its prey. Data from animals wearing sensors revealed that predators were also faster and had better acceleration than their intended dinners. But in simulated hunts, prey animals had the advantage at lower speeds, when their agility enabled them to outmanoeuvre their pursuers.

Predators must be more athletic than their quarry to survive, the authors conclude.

See related News & Views: Evolutionary race as predators hunt prey