An international team of researchers including zoologist Professor Rory Wilson and sports science expert Dr Iwan Griffiths from Swansea University have conducted research revealing techniques used by predators and prey – with some surprising results.
The study, published this month in the journal eLife examines what determines the outcomes of predator-prey interactions in wild animals and how both predators and prey can best increase their chances of success.
Professor Wilson, who pioneered the animal tracking device the Smart ‘Daily Diary’ Tag, said: “We all as children, rushed around the playground trying to catch a friend in a game of tag, thwarted by their speed or sudden swerves and we have all watched high level rugby and football, knowing that the speed and cornering ability of the players can decide the outcome of the match.
“But such games of tag are played daily in the wild as predators such as lions strive to catch their elusive prey. Here though, the consequences of the game are a matter of life or death.”
The team of researchers, led by Swansea University’s Professor Rory Wilson, looked first at how mass should affect an animal’s speed and cornering ability.
Although it is recognised that larger animals tend to be able to run faster, Professor Wilson, working with Dr Iwan Griffiths, highlighted how larger animals actually have to exert greater forces to turn but, perhaps surprisingly, have relatively less capacity to provide the necessary force for this than smaller animals.
Professor Wilson said: “This explains why rhinos have such a wide turning circle compared to gazelles or mice. In the predator-prey game of tag, therefore, bigger predators should face problems trying to run down smaller prey, which should be able to increase their chances of escape by jinking sharply at the right time.”
To see how this theory played out in the wild, Biologist, Dr Mike Scantlebury from the Institute for Global Food Security at Queen’s University Belfast and South African researchers Dr Johnny Wilson and Dr Gus Mills equipped nature’s fastest land animal, the cheetah, with accelerometers to look at how they dealt with variously sized prey.
The tagged cheetahs chased everything from small hares to large wildebeest and ostrich and, true to predictions, were found to turn more often and more sharply when pursuing smaller prey.
Professor Wilson said: “The cheetah study showed how prey use their greatest assets to attempt to escape, whether these assets are speed or manoeuvrability - both of which depend on prey size in relation to that of the predator.
“Ultimately, the predators have to contend with this by trying to predict when prey might swerve but can also enhance their chances of success by hunting in groups or trying to ambush the prey.
“Our study has highlighted the complexity of the chase, but also how the ground rules and solutions are dependent on simple physical principles.
“This might seem a far cry from the playground or the rugby field but perhaps both children and sportsmen could learn a trick or two by casting their eyes on the African savannahs.”
The study is to be published in the journal eLife 0n 7 August 2015.
Story by Mari Hooson
- Friday 7 August 2015 10.12 GMT
- Thursday 10 September 2015 12.26 GMT
- College of Science