Even scientists differ on the exact nature of time, yet they agree on Einstein’s relativity: time is relative. Research shows that different species, including humans, perceive time’s passage in distinct ways. Some animals with faster internal clocks operate on a quicker tempo, while others, especially those that fly or hunt in the sea, experience time differently.
All creatures, humans included, sense the flow of time through their biological rhythms. The internal clock sits in the brain, with key roles played by the hypothalamus, the pineal gland, and the suprachiasmatic nucleus. It is tuned by external cues such as daylight, temperature, seasons, and moon phases.
This internal clock guides behaviors like mating, hibernation, and migration, and scientists have found that similar mechanisms exist in plants, fungi, yeast, and bacteria as well.
The largest study to date examined how quickly samples from more than 100 animal species detect changes in their surroundings. The aim was to understand their temporary perception—how fast or slow changes are perceived over time.
Researchers observed that animals living fast-paced lives tend to have visual systems that detect environmental changes at a higher rate.
Take flies and dragonflies as an example. These species process visual information incredibly rapidly. Their eyes can detect changes up to about 300 hertz, meaning they perceive up to 300 changes per second. For them, time appears to move more slowly than it does for humans, who perceive roughly 65 hertz.
A flycatcher and a starfish
The fastest eyes among vertebrates belong to the pied flycatcher, a songbird capable of perceiving around 146 hertz. Salmon and dogs follow closely, with perceptual rates near 96 and 75 hertz respectively.
“Having fast vision helps a species detect rapid environmental changes. When an animal is moving swiftly or needs to track prey, precise detection of changes proves highly useful,” notes a researcher from the University of Galway in Ireland, one of the study’s authors.
The slowest visual systems were found in the crown-of-thorns starfish, which sees about 0.7 hertz. Time for this species passes quickly, though its average lifespan reaches around 16 years.
When examining a wide range of life—from dragonflies to starfish—researchers concluded that a species’ time perception relates to how swiftly its environment can change, Healy explains.
Such findings enhance understanding of predator-prey interactions and even how light pollution might affect certain species more than others.
One surprising result is that many land predators exhibit relatively slower time perception compared with aquatic predators. The difference is thought to arise because aquatic predators can continually adjust their position as they approach prey, whereas terrestrial predators may rely on brief, decisive bursts once they strike.
Status of football goalkeepers
Fast time perception comes with higher energy costs, linked to how quickly retinal neurons recharge. Species that do not require rapid vision may allocate that energy to growth or reproduction instead.
They are among the most agile animals, moving fast to dodge threats or catch swift prey. A trait that pairs high-speed perception with small body size and rapid metabolism explains why time seems to pass more slowly for these creatures.
Variation in time perception also exists within the same species. For example, some studies suggest that football goalkeepers perceive rapid changes more quickly than their teammates, and caffeine can momentarily influence this perception, though the effect is modest.
How was time perception measured across species? Researchers relied on dozens of prior studies using flashing lights to gauge response. When the light is activated, the speed at which the optic nerve transmits information to the brain is recorded with devices known as electroretinograms, a measure researchers describe as frequency, indicating how fast a flash is detected.
These methods shed light on the remarkable diversity of temporal perception across life in different environments.