How do animals see?

PUSH seen in animals this is made possible by the presence of the retina, which is the photosensitive organ of the eye. Although the eyes of all vertebrates are descended from a common ancestor, they have adapted to life in a myriad of different ecological niches. For this reason, Visual perception can vary enormously between species – so ours also differ from non-human animals – and these differences affect not only what everyone sees, but also how they see it.

Light contains a variety of sensory information that is essential to the daily lives of many animals, from the color of ripening fruit to the detection of an approaching predator. In other words, meaning plays a role essential role for the survival of animals and their interaction with the environment.

How mammals see it

Usually, all vertebrate eyes function somewhat like camera, with a front diaphragm that directs incident light onto a light-sensitive retina that works just like camera film. However, the visual systems of mammals have undergone significant changes during evolution, and their vision differs from that of other vertebrates not so much by the shape of the eye, but by the properties of the retina and its photoreceptorsknown as rods and cones, which are located in the outermost layer.

Rods are located on the periphery of the retina and are responsible for night vision (or scotopic). Highly sensitive to light, when it increases, it quickly becomes “saturated”. The cones are mainly located in the center of the retina and are used for daytime vision (photopic vision). They are activated under conditions high brightness: less sensitive to light, in fact they adapt well to it and allow colors and details to be distinguished.

Dogs

PUSH seeing dogs works well in different lighting conditions. In general, dogs are less good at detecting details than we are; what a person can see clearly at about twenty meters, a dog can see just as clearly at about 7 meters. However, dogs are very good at detecting moving objects, but less so at stationary objects. It is no coincidence that wagging the tail is one of the most important signals for communication, even at a distance. Dogs are somewhat astigmatic, so they focus better on stimuli that are more than 50 cm from the eyes. For the closer ones, they help each other by smell or taste.

Cats

The the sense of sight in cats he adapted well to their lifestyle. They have scotopic vision, as well as a field of view of around 200°, and excellent peripheral vision that allows them to see up to 30° to the side without having to turn their heads, compared to 20° for the human species. They can distinguish between blue, green, yellow and purple. Cats’ eyes are adapted to quickly perceive movement even in the dark, and this helps them detect potential prey and highlight it even against a dark background.

Horses

Horse’s eye it is rich in rods, more so than in humans, and this gives them excellent night vision. Thanks to the lateral position of the eyes, they have a very wide field of vision, which allows them to see more than 350 degrees around them. They can distinguish blue and red from gray, while they have some difficulty with green and yellow.

Monkey

THE primates they have photopic and trichromatic vision. So they detect details well and thanks to the presence of three types of cones, they are able to distinguish red, green and blue colors.

As the birds see

In 1943, a well-known French ophthalmologist Rochon-Duvigneaud described birds simply but effectively and defined them as “eye controlled wings”. The phrase evidently sums up the characteristic features of birds, flight and sight as the main sense. Birds are active in different light levels, so their eyes have developed specific mechanisms to cope with this, adjusting sensitivity and resolution. When an eagle hunts in broad daylight, light levels can be 10^9 times higher than those experienced by an owl hunting in the same area under starlight.

The same eagle can experience a 1000-fold change in light between sunrise and noon, while an owl can experience a 10^6-fold change between sunset and a moonless night. They are present in the bird’s eye four types of conessensitive to long, medium, short and ultraviolet wavelengths of light. As with most reptileshidden inside these cones is a particularly interesting treatment: tiny drops of colored oil that act as microlenses and light filters, greatly improving color discrimination.

How reptiles see

THE reptiles they are considered the only group of animals that includes snakes, lizards, crocodiles and turtles. In fact, it is true that they are all ectodermal and covered with scales, and that in most species, both diurnal and nocturnal, vision is important and thus the eye is relatively large. Phylogeny, however, tells us a different story.

THE dinosaurs and crocodiles they are actually much more closely related to birds than to snakes, lizards, and chelonians, with the split of pangolins (lizards and snakes) from crocodiles and turtles dating back about 200 million years. Added to this is their current adaptation to various ecological niches. These differences explain the existence of remarkable differences between different species of reptiles and between others precisely in their eyes.

snakes

Lens a “watch glass”, very globular and formed by fused transparent lids, covers the eyes of all snakes, so that they appear to be always open. But their eyes are different from those of non-snake scales such as lizards, in part due to the lack of oil droplets in the photoreceptors. That said, it is important to note that eyes vary in anatomical and physiological characteristics even among the approximately 3,500 extant species of snakes. These species inhabit almost every continent except Antarctica and have adapted to a wide variety of different ecological environments.

Among them we find burrowing species, living on trees that are completely aquatic, as well as nocturnal and diurnal species. For example, they range from dorsally located eyes in boa constrictors to laterally located in pythons; from diurnal snakes such as the garter snake, which have retinas full of cones and round pupils, to nocturnal ophidians, which are dominated by rods and slit pupils, which let in more light. At the same time, differences in the field of view are also noted. Laterally placed eyes actually offer a larger, almost panoramic field of vision.

How insects see

When the first dinosaur walked the earth and our human ancestors were crawling in the mud like Newts, insect they were already flying around here, and over the next 400 million years they diverged into at least a million species that made up more than half of all known living organisms. Basically, they are the most successful group in the animal kingdom, and the eyes are the most visible and distinctive part of their head.

Flies

The eyes of flies it differs from the human eye, which has a single lens that flattens and curves to focus objects on a set of retinal photoreceptors, which, as we said, are the camera of the eye. Flies have compound eyes made up of thousands of tiny lenses that create a distinctive mesh-like surface, and they don’t move, so ideally they don’t even adapt. However, beneath the lenses are photoreceptor cells that move quickly and automatically and adjust focus as they sample an image of the world around them.

Basically, then, the eyes of flies project and process the image to form a representation of an environment not too different from that of vertebrates. That means flies too see detailed pictures, or more detailed than once believed, and they also have an extraordinary ability to detect rapid movements, allowing them to engage in high-speed chases. Vision differs from the human species primarily in terms of field of vision and spatial resolution. If you want to know what the world looks like to a fly, imagine an extremely myopic person with myopia of say 14 diopters taking off his glasses.

Which animals see best?

Actually There are no animals that see better than others. From humans to insects, everyone has good vision, regardless of eye shape or position. If anything, there are animals that see Otherwiseand this is a reflection of the unique adaptations that have developed over the course of their evolution.