In fact, it is not only flies that have the same ability to perceive time as we do. Recent studies have shown that in many species, the perception of time is directly related to body size: the smaller the body size and the higher the metabolic rate, the slower time passes.

So how do you measure the ability of various animals to perceive time? This brings us to a value called the "flash fusion critical frequency" (flash frequency value for short). When the flickering frequency of the light source reaches a certain value, the flashes seem to be fused and appear to be continuous, and this frequency is the flash frequency value, which can reflect the ability to perceive time. The images of TV, computer, and cinema screens that we usually watch are actually flickering, but because of their high frequency, we have the illusion of continuous pictures.

"A lot of researchers have studied this phenomenon in different animals by measuring their perception of flickering lights," said Dr. Andre Jackson of Trinity College Dublin, Ireland, who led the study. Flies perceive flashes of light up to four times faster than we do, so it's conceivable that flies basically look at everything in slow motion. ”

Their article, published in the journal Ethology, states that small, agile animals have the best ability to perceive information per unit of time.

Dr. Jackson thinks this may also explain why time seems to pass faster as people get older.

"The idea that children's time passes more slowly than adults' time is appealing, and there is some evidence that it may be so." "Studies have found that for humans, the flicker value is related to a person's subjective perception of time and changes with age, and this value is significantly higher in children," he said. ”

Scientists believe that the perception of time is only one other aspect of evolution and survival.

"The animal's perception of time is important. The ability to perceive time on very small scales can be the difference between life and death for some agile creatures, and our conclusions support this idea," said Kevin Healy, a PhD student at Trinity College Dublin's Institute of Natural Sciences, one of the study's collaborators.

Graeme Ruxton, a professor at the University of St Andrews in Scotland who was also involved in the study, said: "Their eyes can send new information to their brains at a much higher frequency than our eyes, but if the brain can't process it at the same high rate, it's worthless." So this study also tells us that even the smallest animals have amazing abilities in their brains. ”

"Flies may not be deep thinkers, but they make informed choices quickly."

Another member of the team, Dr Luke McNally of the University of Edinburgh, said that some animals can use this differentiation in their ability to perceive time to their advantage: "For example, many species use flickering light as a signal, such as fireflies and many deep-sea animals. The visual system of larger, slower-moving predators may not be able to decipher these signals if they are not fast enough, giving the sender a secret channel of communication. ”

The study covered more than 30 species, including rodents, eels, lizards, chickens, pigeons, dogs, cats, and leatherback turtles, for which time passes relatively quickly because of their larger bodies and slower metabolisms.