Animals' Perception of Time Linked with Body Size and Metabolic Rate

Animals have no need for clocks or telling time in the form of hours and seconds that we are accustomed to, but new research shows that an animals' ability to perceive time is linked to the pace at which they live life.

Small animals with rapidly metabolic rates, such as some birds, perceiving more information in a unit of time, hence experiencing time more slowly than larger animals with slower metabolic rates, such as turtles.

Andrew Jackson, an assistant professor at the School of Natural Sciences at Trinity College Dublin, published the research with colleagues from University of Edinburgh and the University of St Andrews in the journal Animal Behavior.

"Ecology for an organism is all about finding a niche where you can succeed that no-one else can occupy," Jackson said. "Our results suggest that time perception offers an as yet unstudied dimension along which animals can specialize and there is considerable scope to study this system in more detail. We are beginning to understand that there is a whole world of detail out there that only some animals can perceive and it's fascinating to think of how they might perceive the world differently to us."

Lead study author Kevin Healy, a PhD student at Trinity's School of Natural Sciences, said that the results of the research add credence to the notion that time is important for animals.

"Our results lend support to the importance of time perception in animals where the ability to perceive time on very small scales may be the difference between life and death for fast moving organisms such as predators and their prey," Healy said.

The research capitalized on the same principle of perception that TV screens and computer monitors employ, wherein the screen is showing a flashing image so rapidly that our eyes cause it to appear solid and un-flickering. This principle is called critical flicker fusion frequency. What one set of eyes sees as solid, another may see as a flickering image as a result of their eyes having a higher refresh rate than the screen.

"Having eyes that send updates to the brain at much higher frequencies than our eyes do is of no value if the brain cannot process that information equally quickly. Hence, this work highlights the impressive capabilities of even the smallest animal brains. Flies might not be deep thinkers but they can make good decisions very quickly," said professor Graeme Ruxton of the University of St Andrews.