Jeepers, Peepers: Why Spiders Have So Many Eyes
Is it their eight creepy-crawly legs or their eight beady eyes that make spiders a spooky Halloween staple? Either way, new research suggests all those extra pairs of spider peepers have their own roles to play in keeping the arachnids safe.
Jumping spiders, a group of spiders that actively hunts its prey rather than trapping it in webs, have four pairs of eyes (as do most spiders). A new study finds that while the center, or principal, pair of eyes is good at picking out details, one of the side pairs is crucial for warning spiders when something is coming their way.
This “looming response” is the equivalent of a human ducking and covering when a baseball flies toward his or her face. But humans rely on just one pair of eyes to both avoid the baseball and see the details of its stitching. Jumping spiders use four eyes for the same tasks.