The brains of many types of shark are comparable in size and complexity to those of mammals, and enable them to process a wide range of senses. Sharks have the same five senses as humans but can also sense electrical currents and pressure changes.

Taste Electroreception Pressure Changes  

Whitetip Shark nostrils © Ofer Ketter.  

SMELL – Smell is incredibly important to sharks, demonstrated by the fact that up to 2/3rds of the total weight of their brain is used to process smells.

They’re super-sensitive to smells that are important to their survival, including scents produced by potential predators, prey or a mate. Some sharks can detect the blood of a prey item from a huge distance, responding to one part of blood to one million parts of water – the equivalent to one teaspoon in an average sized swimming pool.

Blue Shark eye © Wikimedia Commons, Joxerra Aihartza.

SIGHT- As light doesn’t travel well through water, sharks need to maximise the amount available to help them see. With eyes positioned on the side of their head, they have an excellent field of vision in almost all directions. However, their vision becomes much more acute when just 15m from an object - it's not until this point that sight becomes dominant over their other senses.

Like cats, they also have a ‘tapetum lucidum’ which is a reflective layer of shiny cells that lies behind the retina and improves vision in low light conditions. This adaptation allows nocturnal and deep-water species to hunt effectively in darker, murkier waters and subsequently gives their eyes a green glow in the dark.

Catshark © Lauren Smith.  

SOUND - Sharks have a very acute sense of hearing and are particularly sensitive to low-frequency signals. In field studies scientists have noted that they can track sounds and are particularly attracted to distress sounds emitted from wounded prey.

Their ears are located on either side of their head behind the eyes, and are only visible from the outside as two small holes. These are made up of three cartilage tubes filled with fluid and lined with hair cells. Sound waves cause these tiny hairs to vibrate and the brain then interprets the sound.

Nurse Shark showing barbels © Shane Gross.  

TOUCH - Sharks have multiple nerve endings under their skin and some also have barbells around their mouth that can be used to probe the sand for prey.

They can also sense touch using their teeth, which contain numerous nerves that are pressure sensitive. Lacking hands to feel, sharks will use their teeth to try and identify an object - being inquisitive creatures this can cause a lot of problems, as a ‘test bite’ from a large shark can prove fatal to un-intended prey such as humans.

As well as direct touch, sharks also experience distant touch through the lateral line system.

Shark hunting a seal © William Buchheit.  

TASTE - The taste organs of a shark are not as highly adapted as their other senses because taste is not used to locate prey.

They will often ‘test bite’ a potential meal to see if it's palatable. If the shark doesn't like the taste then the item will be spat out. This possibly accounts for the high survival rate of shark victims, where sharks have accidentally bitten humans, released them and left without further incident.

ampullae of Lorenzini of a Tiger Shark © Wikimedia Commons, Albert Kok.  

ELECTRORECPTION (ampullae of Lorenzini) - Sharks have a complex electro-sensory system which relies on receptors positioned on the head and snout area. These unique receptors are within special jelly-filled sensory organs called the ampullae of Lorenzini. These tiny pores are extremely sensitive and enable a shark to detect even the faintest of electrical fields, such as those generated by the Earth’s geomagnetic field or muscle contractions in prey.

FUN FACT - Hammerhead sharks can locate prey that’s completely buried under the sand, making them experts at hunting stingrays.

The Earth’s geomagnetic field is thought to help sharks orientate themselves and navigate the world’s oceans, which may explain how they’re able to migrate such immense distances so accurately.

Blacktipreef Shark © Alec Connah.  

PRESSURE CHANGES (Lateral Line) – The lateral line alerts a shark to both potential prey and predators. It’s made up of a row of small pores that run all the way from the snout to the tail. Surrounding water flows through these pores and special sensory cells (neuromasts) sense any pressure differences.

The lateral line also gives a shark spatial awareness and the ability to navigate. Their own body movement creates waves that bounce off obstacles (such as reefs), enabling them to create a pressure map of their surroundings.

There is no human equivalent of this sense, because air is not dense enough to feel any pressure differences.


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