How Far Can Spiders See?
WouterIf you are an arachnophobe, you may wonder how far can spiders see. Typically, spiders are only able to see a small area, but some species have very good vision. Some species can even distinguish colors.
Scientists have studied the eyes of jumping spiders. They are similar to those of larger animals. The central pair of eyes has a smaller inner lens that projects an image onto the retina. This is like a tiny binocular. A reflective membrane in the eyes allows the spider to see in low light conditions.
Researchers found that the jumping spiders were able to distinguish color and motion. Their acuity was five to 10 times better than humans. Interestingly, they were also able to see a moon at night.
Another eye was located on the side of the spider’s head. Scientists believe that these are motion detectors. While spiders’ hazy vision is not as accurate as humans’, it can help them pick up movements and changes in air pressure.
These lenses are not able to swivel like human eyes, but they can pivot in order to scan an area. It is this ability that allows the jumping spider to change direction without moving its head.
In fact, the jumping spiders are able to see up to 20 millimeters with clarity. Spiders can also move their retinas up and down. With the aid of muscles attached to their retinas, they are able to rotate their heads to face an object they’re interested in.
