Monday, 21 October 2013

Does time fly for a fly?

by Thien Ho

It appears that time flies for anything but flies – and other small animals. A recent paper published in the journal Animal Behaviour found that the size and metabolic rate of an organism was directly related to its perception of time. The findings, led by Dr Andrew Jackson at Trinity College Dublin in the Republic of Ireland, indicated that smaller animals with faster metabolic rates perceive time in slow motion. Dr Jackson had measured a range of different organisms and their reaction times against individual flashes of fast-flickering light. The scientists then based the measurements on the critical flicker fusion frequency, the point at which the flashes seem to merge together until the light source looks constant, to provide an indication of the time perception in the organisms. It revealed that houseflies saw the light flickering almost seven times faster than humans can, at a rate similar to other small mammals and birds such as squirrels and pigeons. These animals perceive the world in a very different way to everything else as they absorb so much more visual and audio information per second.

“[For the fly] it feels like you are moving so slowly towards them,” Dr Luke McNally, a researcher of Edinburgh University, said. “It's the same as the famous bullet-time scene where the bullets are moving at this incredibly slow rate as far as Keanu Reeves is concerned.” This significantly fast reaction time is the difference between life and death in the wild, especially for smaller animals as their ability to process information quickly is essential in order to escape from predators. Visual systems that send information to the brain at very high frequencies are useless if the brain cannot process it all as quickly. Thus, this research only exposes the impressive abilities of even the smallest brains. “Flies might not be deep thinkers, but they can make good decisions very quickly,” said Professor Graeme Ruxton, who also participated in the research.