Do you know why sheep have rectangular irises?
Sheep have rectangular (or, more accurately, slit-shaped) irises as part of their evolutionary adaptation to being prey animals. This unique shape provides them with an extended field of vision, allowing them to detect predators from various angles. Here’s how it works:
Wide Field of View: The Sheep’s rectangular pupils can expand horizontally, giving them a panoramic field of view of around 270 to 320 degrees. This allows them to see nearly all around themselves without moving their heads, which is crucial for spotting predators.
Better Peripheral Vision: The rectangular shape helps them focus on the horizon, where threats are most likely to appear. This adaptation aids in spotting movement in their surroundings.
Depth Perception and Stability: When sheep lower their heads to graze, their pupils rotate to maintain a horizontal alignment with the ground. This helps them keep a stable image of the terrain and makes them more aware of their environment while eating.
In short, the rectangular shape enhances their survival by improving their ability to detect and respond to potential environmental threats.
