The shark feels cold with the face

To distinguish warm from cold, sharks, burbot and slopes seem to use their heads. According to new data, the mucus that is contained in their nose produces electric current in response to temperature changes.

Similar mucus are present in other animals. The synthetic variety of such a gel can be of interest to the microelectronic industry, reports Nature (translation on the website inopressa.ru ).

Mammals feel the temperature by means of pores in the cell membrane - ion channels. Letting out and releasing ions they produce electric flows that irritate the nerve endings. Earlier it was believed that fish also use the same system.

However, the sharks approached this matter in a completely different side, says the author of the study by physicist Brandon Braun from the University of San Francisco in California. It turns out that these are "the most sensitive to the temperatures of the creature of all known to us."

Brown selected mucus from the skin pores with muzzle. These pores are sensitive to electric fields and, as it were, "scan" the water environment in search of the victim.

It turned out that heating the mucus is only 0.1 degrees Celsius increases its electrical conductivity. Since the skin pores are lined from the inside with nerve cells sensitive to electricity, sharks can feel temperature changes without resorting to ion channels.

This explains how sharks are looking for in the ocean the zones rich in fish, which are formed when water masses of different temperatures collide. Mucus allows them to determine the temperature with an accuracy of 0.001 degrees Celsius.

From a chemical point of view, this mucus is similar to an ordinary gelatin. Perhaps its electrical properties in the case of sharks are unique, perhaps any similar gel will also behave. Brown has already outlined a preliminary experiment to find out: "I will make jelly on sea water and compare with the kakuli mucus."

Gel, similar to the properties with solid semiconductors, was discovered for the first time. Think, Brown fantasizes, such a synthetic gel can be covered with electric circuits sensitive to temperatures, which will allow them to give excess heat after passing the current.