Richmond Hill Pest Control: Why Do Spiders Need Eight Eyes?

Why Do Spiders Need Eight Eyes

While spiders prefer to live in dark, quiet corners away from humans, they can make nuisances of themselves by building elaborate webs. Ultimately, they may require spider pest control in Richmond Hill. Some people are afraid of spiders, and part of the reason may be that their anatomy and physiology are so different from ours.

For example, humans and most other animals, including mammals, birds, reptiles, and fish, have only two eyes. Most spiders have eight eyes, and even that number is not constant. Across the 34,000 species of spiders on Planet Earth, some have six eyes, some have as many as 12, and some need none at all.

Why Do Spiders Need So Many Eyes?

Human eyes are much more complex than spider eyes. They are equipped to perform many more tasks so that people only need two eyes. Spider eyes are less complex and each is only equipped to do certain things. Therefore, spiders often need more eyes to carry out multiple visual functions.

How Do Spider Eyes Work?

In spiders with eight eyes, two are often very large and face forward, as human eyes do. These eyes function similarly to the ways that human eyes do to perceive colour and judge distance. This is especially important for jumping spiders that pounce on their prey rather than catching it in a web.

Spiders are unable to turn their heads because they don’t have necks. If they didn’t have a way to see behind them, they would be easy prey. Therefore, in addition to the two big eyes upfront, many spiders also have a row of eyes along either side of their heads. These are smaller and less complex than the two eyes in front. Their job is to detect motion from behind the spider that could be a predator. When perceiving motion with these eyes, spiders can react instinctively to get out of the way. If you have ever noticed a spider skittering away when you get too close, it may be because the eyes along the side of its head saw you moving.

Different species of spiders have different ocular adaptations based on their lifestyle. For example, wolf spiders have evolved the ability to detect movement in the dark. Their eyes are similar to that of a cat or dog in that when you shine a light on them, they appear to glow because of the reflection off the back of their eyes. Wolf spiders are nocturnal, and this eye adaptation helps them make the most out of the dim light available to help them catch their prey.

Why Do Some Spiders Have No Eyes?

The rule of evolution is “use it or lose it.” Traits that are not advantageous to a species eventually disappear. For example, there are some spiders that live all their lives in complete darkness because they live in caves. Even if they had eyes, it wouldn’t do them any good because it is impossible to see without light. These spiders developed other ways of finding food, and the eyes eventually evolved away completely.

Do More Eyes Mean That Spiders See Better?

Some spiders have better eyesight than others, at least according to human standards. Spiders that need to judge the distance to catch food, such as jumping spiders and net-casting spiders, have more acute vision than others. Spiders that do not have good vision rely primarily on other senses, such as taste, touch, and vibration. For example, a spider that spins a web is sensitive enough to know immediately when it is disturbed and goes immediately to catch its prey.

Spider Pest Control in Richmond Hill From Truly Nolen

Spiders aren’t necessarily the worst pests, but if you see a lot of them around, you may need indoor spider control. We offer preventative services as well as helping you deal with a full-blown infestation. Find out more about our comprehensive, pet-friendly services.