Spiders have so many eyes because they can’t turn their heads, so these eyes assist them to assess the environment around them and allow them to better see their surroundings.
Evolutionary speaking, these eyes play an important role for some spider species, while for others, they’re not as important. Tarantulas, for example, have eight eyes but they can’t see very well. Hunting spiders, on the other hand, will be able to see much better using their eyes – for example, wolf spiders.
Why Do Spiders Have so Many Eyes?
The primary reason is that spiders can’t turn their heads and can’t turn sharply very quickly, so they have eyes on all locations of their cephalothorax.
The vast majority of spiders have eight eyes, while others also have four or six. Some spiders have up to 12 eyes, while other spider species don’t have eyes at all, using other senses to survive.
Most spiders with eight eyes have their eyes positioned strategically. Most have two rows of four eyes, with each eye enabling them to see in one specific direction.
If you combine all the eyes, the spiders get a picture of their surroundings. Because spiders also have eyes on the sides of their cephalothorax, they can see much wider than the eyes of humans allow us to do, for instance.
Another reason why spiders have so many eyes is evolution.
Some spider species grow up in denser habitats with a lot of vegetation, while others get used to open areas much more. Likely, those who live in denser habitats will not use their eyesight as prominently as those who live in more open habitats. Tarantulas, for instance, rely on their hair more than their eyes because of this.
Hunting spiders, on the other hand, will use their eyes more prominently. Wolf spiders or jumping spiders are two good examples of this.
Can Spiders See?
Yes, spiders can see, but not all spiders can see equally. Some spiders like the tarantula will depend on other senses because their eyesight is not very good. Hunting spiders, on the other hand, will depend on their eyesight more.
Not all spiders have the same levels of eyesight quality. Some spiders have their eyes positioned differently than others, and they also have different types of eyes.
The most common types of eyes include:
- Reflective eyes – these are used by most predators. These eyes have a tapetum, which allows these spiders to see in the dark. As a result, these eyes will shine when they are exposed to light, which you might be able to observe with some hunting spider species.
- Searchlight eyes – some spiders have two larger eyes positioned on their backs, as they act as searchlights. These will allow the spider to spot motions and other animals behind them, which gives them an important edge over potential predators and other animals.
The quality of spider eyesight will also depend on the habitat of the spider, and its hunting techniques.
Hunting spiders like wolf spiders or jumping spiders are likely to have better eyesight than spiders that rely on their webs for hunting. They need to use their eyes when they’re chasing down their targets, giving them a better idea of where they have to run to catch their prey.
On the other hand, web-making spiders often live in more dense vegetations, so they don’t have to rely on their sight as much. They’ll use their hairs or even their webs to detect their surroundings, which is crucial for their survival.
Can Spiders See You?
Some spider species will be able to see you, while others might not. The vast majority of spiders will only be able to recognize your shape and they will be intimidated by you, while others will be able to see more detail.
Most pet spiders like tarantulas, for example, will sadly not be able to recognize you. This is mainly because their eyesight is not very good, and they’re only able to recognize larger shapes and distinguish light from the darkness.
Other hunting spiders like wolf spiders, might be able to see your face in a bit more detail, though.
If you own of these hunting spiders, you might have a bit more luck in getting them to recognize you, which might create a better relationship between you and the spider. However, this will not always be the case.
Most spiders use their eyes to recognize larger objects and shapes. However, their eyes are not good enough for them to help them see details such as your face or the features of your face.
Do All Spiders Have 8 Eyes?
Not all spiders have eight eyes. The vast majority of the spider species have eight eyes, but some spiders have no eyes, while others might have up to 12 eyes.
Very few of the spiders that have eight eyes also have good eyesight, though. Some of these spiders like to rely on other senses like their vibrations for survival. Some will also rely on touch and other senses instead of using their eyesight.
Some spiders have no eyes at all. A good example of this is a special type of huntsman spider which lives in caves and other dark areas. This spider relies on other senses for survival like vibrations and touch. It uses these senses to hunt other animals and their prey.
On the other hand, there are also some spider species that have 10 eyes or even 12 eyes. These spiders have their eyes scattered proportionally throughout their entire bodies, and they assist them with everyday tasks like hunting and escaping predators.
Most spiders have eight eyes, and these assist the spider in seeing in all directions. They can’t turn their heads around which means they have to rely on their eyes to see in different directions. The eyesight of most spiders is not that good and it’s usually not the primary type of sense they use to feel the world around them.