BBC: Smaller animals have quicker reaction times than larger ones because of their ability to more quickly perceive changes in their environment, says a group of researchers from Ireland and the UK. In their paper published in the journal Animal Behaviour, Andrew Jackson of Trinity College Dublin and colleagues describe how they used a flashing light to determine the speed at which the eyes of various vertebrates could process visual information. They found that certain insects and small birds, for example, have the fastest visual systems and thus see time as passing in slow motion; the reverse is true for larger animals. That ability probably helps small creatures escape from larger predators. Similar visual acuity has been observed in humans. Accomplished athletes, such as goalkeepers or racecar drivers, are able to very quickly determine where a ball is coming from or guide a speeding car along a course. However, according to Jackson, humans are reaching their limits regarding speed—to go any faster will require either computer assistance, drugs, or visual implants.