Friday 27 April 2012

7th Sense

The seventh sense is the pressure sensors.
Lateral line
The lateral line system of sharks extends from the head to the caudal fin. It contains sensory cells embedded in jelly and is connected to the skin surface by small pores. The jelly conducts shock waves to the sensory cells.

Pit Organ
The pit organ consists of two oversized denticles which cover a small pocket in the skin. At the bottom of this pocket is a collection of sensory hair cells. Many sharks have these pit organs in greater numbers on their backs, sides and lower jaw. The exact function of the pit organ has not yet been determined, but most likely sharks use it to register mechanical stimuli such as water currents.

6th Sense

The sixth sense is touch. Shark skin has highly sensitive pressure and temperature sensors, some of which are so sensitive that they can register skin vibrations/movements of only 0.02mm. With these sensors sharks can feel contacts, water currents and temperature changes.

5th Sense

The fifth sense is hearing. Sound travels under water about four times faster than on land, whereby low frequencies dissipate slower than high ones. The sense of hearing is thus important to sharks. They react especially to low frequency, pulsating oscillations around 100 Hz, as produced by sick or wounded animals. Several shark species can thus accurately locate their prey over a distance of several hundred meters.

4th Sense

he forth sense is the electrosenses. Probably the most fascinating sensory performance of sharks is their ability to detect electrical fields. All living things emit electrical fields, either with the beat of the heart, muscle movement or with the brain. Animal prey can effectively hide or camouflage themselves, but they cannot conceal their electrical fields.
The shark's electrosensor are its Lorenzini ampoules. Only sharks or rays have them. They consist of the ampoule and a long canal filled with a jelly-like substance which ends in a pore. Hundreds of such pore groups are located on the shark's head, especially in the region of their snout. Since the electrical impulses of prey animals are very weak, the electrosensors only function within a range of several centimeters.

3rd Sense

The third sense is taste. The decision on whether or not to eat a prey depends on how it tastes. Sharks have a very good sense of taste so it is not astonishing to hear about their tendency to first try anything unknown to them before eating it completely.

2nd Sense

The second sense is scent. The shark can smell certain substances 10,000 times better than humans, and can locate the smell of prey accurately over hundreds of meters.

1st Sense

The first sense of a shark is vision. Sharks have excellent eye sight. A shark can see under water from an immediate range of 0-50 meters, depending on water conditions. In addition, colors are absorbed more strongly further down. Sharks have developed methods of amplifying light in their eyes which make them more efficient than such night-hunting mammals as cats, foxes or wolves.