The nervous system of hairy crabs is also quite peculiar, and it can even be said to subvert our common sense. Because hairy crabs have a central nervous system on the back and abdomen. It is made up of nerves emitted by ganglia.
The ganglia of the brain emit nerves made up of antennae, optic nerves, and cutaneous nerves, among others. So the brain nerves control the hairy crab's visual signals, tactile signals and skin sensations, growing.
The thoracic nerve in the chest is unusually larger than the cranial nerve. The ganglion-derived nerves of the chest are distributed to the individual thoracic feet and extend backwards to the abdominal nerves. There are particularly many branches, and the thoracic nerve is close to the abdomen, so hairy crabs are compared to the shell. Its abdomen will feel more sensitive, which makes people wonder whether the hairy crab controls the body by the brain or by the ganglia of the chest.
However, it is clear that the hairy crab must be controlled by the ganglia of the head. But surely people will be curious, since it is two ganglia, then the hairy crab is not the upper body can not control the lower body?
Of course, there will be no such problem because the brain nerve and thoracic nerve of the hairy crab are linked to a pair of peropharyngeal nerves, and because of this peropharyngeal nerve, the hairy crab can coordinate the two ganglia and complement each other.
The sensory organs of hairy crabs are very developed, not only have a very dreamy visual touch, but even the sense of taste and smell are very developed.
The eyes of hairy crabs are composed of many small eyes, which are not only very sensitive to changes in light and shade, but also have a much stronger visual ability than we humans. Moreover, the hairy crabs are all over the body's antennae and bristles, which are the sensory organs of hairy crabs, which can be described as pulling a hair and moving the whole body.
And the first antennae of the hairy crab have a sensory hair specifically responsible for the sense of smell, which can analyze the smell dissolved in the water. Not only hairy crabs, but it can also analyze the quality of water. So hairy crabs can always find places with clean water.
The first antennae of the hairy crab and the sensory hair above the second jaw foot also have this taste sensing function, so any changes around the hairy crab cannot escape the observation of the hairy crab.
Therefore, every time there is any change, the hairy crab can judge according to the information felt by its own sensory organs, and then react quickly after analysis. It is precisely because of these skills of hairy crabs. Therefore, hairy crabs can repeatedly escape from danger.