Saturday, August 08, 2015 05:21 PM

THE EYES HAVE IT: WHAT PUPILS REVEAL ABOUT PREDATORS AND PREY

Have you ever wondered why your cat has long slits for pupils?

Scientists from the Universities of CaliforniaBerkeley and Durham in Britain have discovered[1] that eye shape can reveal whether a species is predator or prey. Their research appears in the current issue of Science Advances[2]. After analyzing the eyes of 214 species of land animals, they discovered that pupil shapes are directly linked to an animals ecological niche.

For instance, animals with pupils that are vertically elongated, like domestic cats and geckos, are more likely to be ambush predators hunters active day and night who use stealth, not strength or speed, to overcome their prey.

Animals with horizontally elongated pupils, such as goats and sheep, are likely to be plant-eating prey animals, the researchers found. Circular pupils, found in humans and birds, provide good all-around vision and are linked to animals that chase down their prey.

Martin Banks, professor of optometry at Berkeley, and Gordon Love, director of the Centre for Advanced Instrumentation at Durham, say that prey animals have two key visual requirements: spotting and fleeing predators.

"To detect approaching predators ...

News source: Christian Science Monitor

See also: Wake Opthalmology