Quick shark facts
- Sharks have been around for 400 million years
- Pre-dating dinosaurs and even trees!
- They have had little need to evolve
- A testament to just how effective their anatomical make-up is.
- There are over 400 types of shark
- 500 known species if you include those that are extinct.
- Sharks vary widely in size
- From the 8 inch pygmy lantern shark, right up to the 60ft whale shark.
- Despite their negative portrayal in media and film, shark attacks are extremely rare
- You’re more likely to be crushed by a falling vending machine, or be struck by lightning.
- Shark anatomy is fairly consistent across the species
- But each have their own unique features.
- Sharks have skeletons made up of cartilage rather than bone
- Cartilage is more durable and lighter than bone, helping the shark save energy.
- Unlike most fish, sharks don’t have a gas-filled swim bladder
- Instead, they have an oil filled liver that offers buoyancy, using this in conjunction with forward movement to control vertical position.
- The jaws of sharks are not attached to their skull
- They move separately , allowing them to thrust forward and latch onto prey.
- The surface of a shark’s jaws have extra support called ‘tesserae’
- These tiny hexagonal plates are made up of calcium salt deposits, giving cartilage more strength.
- Shark’s may have up to 3,000 teeth at one time
- They are fully embedded into the gums, with shape and size varying depending on their purpose.
- Sharks continuously grow multiple rows of teeth
- When a shark breaks or loses a tooth, a new one moves forward to replace it, much like a conveyor belt.
- It’s estimated that some sharks may lose 30,000 or more teeth in their lifetime!
- Tooth replacement rates vary from several days to several months.
- Most sharks have 8 rigid fins
- A pair of pectoral fins, a pair of pelvic fins, one or two dorsal fins, an anal fin and a caudal fin (tail).
- All sharks are carnivorous
- Ranging from small bivalves and crustaceans, to seals and even other sharks.
- Sharks can be found in all seas
- They generally avoid fresh water with the exception of some species, and are commonly found to a depth of 2,000 meters.
- Not all sharks are solitary
- Many sharks a very social, hunting in packs or congregating in large numbers during breeding.
- Sharks need to keep moving in order to breathe
- Some species have evolved to remain stationary, resting on the sea bed and pumping water over their gills.
- Sharks never enter a true state of sleep
- Some species are able to ‘sleep swim’, as their swimming is coordinated by their spinal cord as opposed to their brain.
- Sharks can detect blood at one part per million
- They can even determine the direction of a particular scent based on the time it takes to reach one nostril compared to the other.
- Sharks have keen eyesight
- As well as their acute smell, sharks have great eyesight even in dimly lit environments. This is due to a mirror like layer in the back of the eye called the tapetum lucidum (the same found in cats).
- Sharks have ears
- Located within a small opening on each side of their head. Sound travels faster in water, and sharks rely on sound heavily.
- Sharks can detect electricity
- Sharks have electroreceptor organs called ‘ampullae of Lorenzini’, and they use this to detect electromagnetic fields which all living creatures emit.
- Most sharks live 20-30 years
- Maturing slowly and reaching a reproductive age anywhere from 12 to 15 years
- Sharks are a k-selected species
- This means they produce a small number of larger, more developed young, as opposed to a mass number of under developed young.
Experience the world of sharks for yourself!
our shark expeditions
