A great white ” nose” best

Have you ever wondered how a shark is so accurate and can smell something miles away? Maybe its because it smelled something fishy? Who nose? But let’s take a look at the tip of the issue. Did you know touching a shark’s nose sends them into a trance-like state? Please DO NOT EVER try and touch a shark’s nose – EVER (including in a cage!). Ten fingers, ten toes and smiles are what we want the most.

Since we are at Blog number 5 I thought I’d switch it up and talk about the big FIVE senses starting with the smell or nose. Actually, sharks have seven senses – which includes the Ampullae of Lorenzini and the Lateral Line

A shark is able to detect scents from far away – up to 1ml of blood in 100l of water. This is done through the use of nares, two nostril-like short duct holes on the underside of the snout. These two openings are divided by a nasal flap. These are meant for smelling and not breathing.

great white nose

Nostrils

Water enters the two forward facing nostrils through the incurrent aperture (they suck in water) and travels through the olfactory sac and exits through the excurrent aperture (flows out).

great white sense of smell

great white nose radar

Close up of the Ampullae of Lorenzini of a Porbeagle Shark Lamna nasus. A series of jelly filled sacks around the snout that sense weak electric signals in the sharks surroundings. Used to locate prey.

Inside the nostril are folds of skin called sensory cells. These folds have a larger area which allows for a more accurate smell. These folds are made up of finger-like cells called cilia which are stimulated by the water and sends a chemosensory message to the brain about the dissolved molecules in the water.

These cilia endings pick-up the scent when a shark “smells” prey or pheromones in nearby deaths of other sharks and during the mating season, which gives the shark a more accurate direction of the scent.

A shark picks up the scent by moving its head sideways. This allows the snout to pass through the scent to determine a trail and direction. If the scent is too wide the shark swims in a large S-shape until it is easier to narrow the trail direction.

Some sharks have barbels (near the nostrils). They are whiskers that work as “feelers.”

Ampullae of Lorenzini

The snout of a shark is covered with many tiny jelly-like electroreceptors called the Ampullae of Lorenzi. These pores, gelatinous canals, that cover the shark’s head connects to a membranous sac (ampulla) and are an intricate sensory network that detects weak bio-electrical signals, of up to 25Hz frequency, within a short range. It is speculated to detect temperature, salinity, mechanical stimuli and magnetic fields. This is how they are able to detect the movements of an animal splashing nearby in the water.

Did You Know? Sharks can navigate the globe by tracking earth’s electromagnetic field

Lateral Line

great white

The lateral line is a sense system consisting of hairy-like tubes under the skin of the shark’s head and sides of the body. These pores are small sensory cells that are sensitive to electrical fields which allow them to detect low frequency sounds, distance perception, currents and turbulence in water such as a seal swimming in the water.

I smell a bad pun coming… Who nose what it’ll be like?

 

J