Sharks have the ability to smell in a similar manner to other mammals; the olfactory senses of a shark are precise, allowing it to smell accurately. The shark has two nostrils, one on each side of its snout. After it picks up the scent of food, the shark swims in a side-to-side manner, which allows it to remain on the right path as its olfactory sense continually picks up the scent of its prey as it swims.
Sharks have the ability to see underwater, and they can see in the deep, dark portions of the ocean. In fact, their heightened sense of sight allows them to see well enough to maneuver through murky and sandy waters. Sharks possess the ability to consciously dilate the pupils in their eyes, which makes them naturally adept at seeing in low light. Sharks that live in the deeper sections of the ocean where natural light is not readily available have an advantage in hunting their prey.
Sharks do not typically use the sense of touch to investigate and feel objects as other mammals tend to do. The sense of touch on a shark is to help the shark sense disturbances in the surrounding water, such as vibrations that may signal danger, other predators or potential food. Canals housing the nerves relevant to the sense of touch run the length of a shark, with a higher concentration on the head. This sense of touch allows sharks to use vibrations coupled with sight and smell to help seek out food.
A shark has a sense of taste similar to other mammals, including humans. This sense of taste is what draws sharks back to feast upon certain prey over and over again, as sharks prefer the taste of certain animals over others. The interior portion of a shark's mouth is lined with taste sensors that trigger brain response to determine whether the taste is something suitable for the shark. Taste is one of the last senses used by sharks when hunting or capturing prey; sharks will bite or eat first and then determine if the taste is suitable or palatable.
One of the unique senses found in sharks is the ability to sense through electroreception, an ability that is facilitated by the large pores on the exterior of the shark. Within the pores resides a gelatinous material that is connected to nerves flowing through the body. As a shark gets close to prey, the electric currents emitted by the prey are detected by the shark; they increase in intensity as the shark draws closer. This electroreception sense tends to take over once a shark has its prey within sight.
The ability of a shark to hear is slightly different from mammals living above the water. A shark does have a sense of hearing, but scientists have yet to prove to what extent a shark can hear. Sharks have ears, and the sense of hearing is mostly used by sharks as a stabilizer for balance. The inner ear of a shark, not unlike humans, helps regulate balance and stave off imbalance. A shark's sense of hearing also works in conjunction with its sense of touch to help the shark detect vibrations and disturbances.