![]() ![]() The vertical slits in cats undergo a 135-fold change in area between constricted and dilated states while humans have only about a 15-fold change. Constricting circular pupils, like humans have, use ring-shaped muscles but vertical-slit pupils have two extra side muscles that more strongly open or close the pupil, allowing a larger change of area. Like the aperture in a camera, the pupil’s function is to regulate the amount of light that enters the eye by constricting (closing) or dilating (opening) the pupil. The vertical slit has optical features that make it ideal for that. The researchers noted that these predators need to accurately judge the distance to pounce on their prey. Such animals include foxes, some reptiles and, yes, domestic cats. This shape and placement gives these animals a panoramic view so they can scan for danger in all directions while grazing.Īnd vertical-slit pupils? Animals with vertically elongated pupils were likely to be ambush predators, animals who lie in wait to kill their prey, who hunt during the day and night and, like most predators, have forward-facing eyes. Animals with horizontally elongated pupils tended to be plant-eating prey species with eyes located on the sides of their head for instance, deer, sheep, and horses. Round pupils were linked to “active foragers,” taller animals such as wolves, lions, and tigers, that chase down their prey. Martin Banks, a University of California at Berkeley professor of optometry, and co-author Gordon Love, a professor of physics at Durham University, found a striking correlation between pupil shape and ecological niche in the animal kingdom that is, their foraging mode and time of the day they are active. Pupils come in a variety of different shapes, but why? In their analysis of 214 land animals, the scientists looked at the animal’s lifestyle (foraging mode, active in the day, night, or both), eye placement on the head, and three pupil shapes–round, horizontal, and vertical. Recently a group of scientists were also curious about the significance of pupil shapes in terrestrial species. One of her questions after closely observing Blue as she sat on the chair arm was, “Why do cats have vertical pupils?” Good question, Mom. Learning to live with her new feline housemate, Mom often asks “why do cats…” questions. Mom and Blue have developed a routine and bonded in the comfort of a favorite chair. That changed three years ago when my sister rescued a tiny, tailless, longhaired black kitten who was malnourished and had broken and missing teeth. Because she has severe allergies and asthma, the last and only cat she lived with in my lifetime was nine lives ago way back when I was in high school. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |