Hey, what a fantastic question!
Everyone knows that animals experience time to some extent—I know my dog always seem to know when it’s time for dinner—but it’s thought that animals’ memories aren’t tied to the passing of time like human memories are. Humans live life linearly, and our ability to remember the order of past events and predict future events plays a large role in our perception of time. Animals, on the other hand, are believed to have a less “episodic” view of time, and live more in the moment.
Human time doesn’t have a lot of significance to animals, because they have no needs for clocks and hours and seconds, so it’s important to think about time in a different way. Perception of time isn’t only about remembering what events happened when, but it’s also linked to how quickly we can process the world around us.
There was a recent study (September 2013) published in Animal Behaviour that suggests that the speed at which creatures perceive time is linked to their metabolic rate. (See: how metabolic rate is linked to life span.) The researchers used a technique called “critical flicker fusion frequency”—basically, measuring the speed at which the eye can process light—and found a strong relationship between body size and how quickly the eye responds to changing visual information.
Small animals with fast metabolisms, like birds and insects, take in more information per unit of time. This means they experience time slower than larger animals with slower metabolisms, like turtles and elephants. They can actually perceive time as if it’s passing in slow motion, meaning they can observe movements and events on a finer timescale. This would definitely be an advantage in some situations, increasing their reaction times and allowing them to escape—like dodging bullets in The Matrix—from larger creatures who perceive time slower, and so might miss things smaller animals can spot rapidly.
Some of the fastest visual systems recorded by the researchers included golden mantled ground squirrels, starlings and pigeons.
As the lead author of the study, Kevin Healy, remarked: “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.”
So there’s still a significant amount of study to be done, but it’s a really intriguing question, and it seems so far that differently-sized animals experience time—i.e., perceive events—on different time scales!