Which animal has the most senses?

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totally phenomenal - senses

The concept of whiskers

  • The whisker hairs of a mouse cover an area that roughly corresponds to the cross-section of the mouse

Whiskers or whiskers, also called sinus hairs or vibrissae, support the sense of touch of many mammals, especially land predators and rodents, but also seals. The hair is mainly on the face and also on the legs and paws and is extraordinarily long and firm compared to the rest of the body hair. While the tactile sensors in the snout are responsible for direct contact, the whiskers explore the wider area.

They help with feeling because their roots, the hair follicle, are entwined with fine nerve endings. If the tip of the hair is deflected, the other end also moves according to the lever principle. The arrangement of the hair gives the animals good feedback about objects, prey or air movements in the immediate vicinity, even in the dark. In cats, the whiskers report in advance whether their body will fit through an opening. Horses and cattle use it to inspect their feed.

  • Sectional view of the skin with the hair follicle

Rats, rabbits and other rodents also use their vibrissae for orientation. Moles and naked moles, which mainly live underground, have numerous whisker hairs on their faces, paws and also the tip of their tails and feel vibrations from the earth. For the naked mole rat, the whiskers are the only body hair, but they even have some in their mouths.

In domestic cats and dogs, it is particularly easy to observe how they actively use the whiskers around the muzzle and above the eyes for exploration. If they stand wide and forward, the animal is alert, tense and ready for the unknown. If the hair is standing sideways or laid back, the animal is more relaxed or shy.

Essential hair

An unusually large area is assigned to the signals from these whiskers in the animal's brain. If they lose their vibrissae, for example through an accident, fire or thoughtless cutting off, an important part of their sensory perception is deprived of them. They move much more awkwardly, and some animals even starve to death.

In mammals, tactile organs are always either the whiskers (vibrissae) on various parts of the body or an arrangement of the various mechanoreceptors. Compared to humans, however, the touch cells are arranged much more densely in the skin. For example, the dog's snout or the pig's trunk is many times more sensitive than the human tongue. The animals receive a much more detailed picture of their environment by simply touching them than even a blind person who is optimally trained to feel.

  • Elephants explore their surroundings with the help of their trunk

Elephants

The trunk is also the most important organ of touch in elephants. Countless sensor cells at its tip reveal details of its surroundings. This is also necessary because elephants see relatively poorly.

So they not only scan their food, but also the path in front of them before they put their feet there. Elephants are very careful and would leave the china shop undamaged if they didn't panic or anger.

One myth, however, is that elephants can hear with their feet. They can communicate over long distances by emitting low humming tones in the infrasound range, which are inaudible to humans and which can also propagate as vibrations in the steppe floor. But you perceive the tones with your ears.

Vibration sensors in the feet can only be found in spiders and other articulated animals - or indirectly in cats or moles that have vibes sitting there.

The birds' sense of touch

The sense of touch is also very important for birds. The pressure information on the feathers when flying is automatically converted by the brain into the correct wing position. But many birds also use their sense of touch when ingesting food: their beaks and tongues are surprisingly sensitive, especially in worm- and maggot-eating birds. They have to feel their prey in shallow water, in muddy silt, in dark ground or behind barked bark. Birds that climb trees a lot or walk along the trunk also use tactile receptors in their feet.

Insects, spiders and other arthropods

Insects (six legs), spiders (eight legs), and other arthropods such as scorpions do not have flexible skin like mammals. Your body sits in a more or less rigid exoskeleton. This is why their tactile organs are found either on feelers, legs, claws or hair, which are distributed over the body.

  • Scorpions have tactile organs, the comb organs and comb teeth on the underside of the body

Insects such as butterflies, beetles, but also cockroaches have feelers or antennae at the tips of which various sensory organs are bundled. Mechanoreceptors sit next to sensory cells for smell or temperature and help to find food and assess the environment. Small flies e.g. B. can use it to estimate the wind strength so that they are not blown away. In water striders, however, the mechanoreceptors sit on the legs so that they can quickly perceive vibrations on the surface of the water.

In addition, there are often buttons on the mouth parts, so-called palps, which check the food again before eating. And whisker hairs on the legs ensure that no touch, shock or air flow goes unnoticed.

  • Tarantulas have a lot of whiskers on their legs

Feel shocks

While insects are usually barely hairy, spiders have much more whiskers, but also special mechanoreceptors, e.g. B. cleft sense organs, in the leg joints. In addition, the first pair of legs is often no longer used for walking, but has been converted into a button and often as a gripper. The web-building spiders in particular are designed to feel vibrations. When they sit on the edge of the net, they not only notice that a prey has gone into the net. From the vibration itself you can also deduce quite precisely what kind of fidgeting there and how big it is. The spiders also recognize when a partner approaches to mate. And if the spider has been away from the web for a while, it will wiggle it briefly when it returns in order to determine from the vibration whether it has caught any prey in the meantime.

Tarantulas are covered over and over with a fur made of whisker hair: They live in narrow caves and passages and are dependent on constantly scanning their surroundings with all their hair. She cannot see her prey or her offspring in the dark, but can feel them perfectly.