Spiders settled on all continents except Antarctica. Now there are more than 42 thousand species. These living creatures, which appeared on the earth millions of years ago, are so peculiar that they were separated into a separate family. Each species of arachnids has its own characteristics of the structure of the body. They differ between themselves and lifestyle. Thebiggest did a little research, and the subject was amazing eyes and the eyesight of spiders.
Photos and facts about the amazing eyes of spiders:
How many pairs of eyes a spider has
During the evolutionary development of different species, a special structure of vision and the number of eyes formed. Their number depends on the way of life and the way of hunting arachnids. Animals that prefer to hunt using professionally woven cobweb networks have poor eyesight. Active hunters see better. Basically, these are 4 pairs arranged in rows. Why spider 8 eyes due to his lifestyle. All eight provide them with a magnificent horizons of 3,600.
In nature, there are species that have 12 eyes, and there are those who manage with just one pair of organs of vision. But even one couple ensures their existence in the world around them. Everything in nature is thought out to the smallest detail.
Individual individuals
The spider-cross looks at the world around him with eight eyes. He hunts at night, and therefore the work of his organs of vision resembles the work of a video camera operating in night mode. But if the camera perceives infrared light, then the eyes of the spider have polarized radiation.
A horse spider with eight eyes arranged in three rows is able to determine the distance to the subject. He measures the exact distance with the front main eyes. They consist of four photosensitive layers. During the hunt, they help him accurately aim. Arachnology has even established that horses distinguish colors.
In the photo: Araneus diadematus
Cave spiders are almost blind, and rely on other senses as much as possible. The smallest eyes are in orbiting spiders. For example, Araneus diadematus simply picks up movement when a victim falls into his net.
Types and structure of the eyes
The amazing inhabitants of the planet have three main types of eyes:
- The main pair. They are also called medial;
- Lateral additional, so to speak, secondary;
- Faceted
The main pair helps the pack track the victim. These eyes are the largest and are located in front of the rest of the visual organs. A layer of photosensitive cells is located inside the capsule of the medial eyes, and muscles are attached to the eyes themselves, whose task is to move the retina.
The lateral ocelli are smaller than the main ones, and are in a static state. They expand the viewing angle, fix the light source. They help to assess the situation around, as well as notice the danger and prey.
Not all species have faceted eyes, but it is they that help spiders to perceive colors. These organs, inherited from distant ancestors, are able to perceive and reflect light.
Benefits
The time has come to tell you what advantages spiders provide their organs of vision and their structure.
- Firstly, the number and structure of the eyes allows you to see a more detailed picture. She is even better than a person;
- Secondly, with the help of the first pair they see a close-up;
- Thirdly, they are shortsighted. Objects that are beyond the limit of 10 cm, they see worse than those that are close;
- Fourth, they have the ability to see ultraviolet light and perceive polarized light;
- Fifth, they accurately determine the distance to the object, see everything that is happening around them and with the help of their eyes can easily navigate in the grass.
Worldview Features
Spiders differ from other inhabitants of the planet in the number and location of their organs of vision.
Each optical organ sees a separate area, but for the animal, the world develops into a single picture.
They do not have to constantly turn their heads to see what is on the side or back.
The organs of vision are distinguished by their structure, and each performs its own special function, helping the spider navigate the world around it.
Associations
Looking at photos of amazing creatures, one gets the feeling that they came from other planets. Their eyes differ in functionality, size.
With the help of modern cameras, you can see the color nearby, as well as the location of the eyes on the body. Someone in one row, and someone in three, or even four.
By the way, on our site thebiggest.ru you can find out what is the largest spider in the world.
Summary
The science that studies these mysterious and slightly frightening creatures is called arachnology. Brave people study them, since most residents of cities and towns are afraid and have a negative attitude towards arachnid creatures. For some, insurmountable fear does not even cause the spider itself, but even its image. They are widely represented in culture, and their images are still found on the vases of the Sumerian kingdom and on the walls of the tombs of Ancient Egypt. The editorial board of TheBiggest.ru asks all people who care about spiders to write a comment about this article. How much do you like or dislike the eyes of spiders and do you find them unpleasant and scary? And below we will post some more beautiful photos of spider eyes.
That's all! But for those who are few, on our Zen channel we continue to publish photos of the eyes of spiders.
Article author: Valery Skiba