Sharks and Rays – Akvarijum Boka

Fascinating Facts on the Sharks and Rays

Sharks and Rays…

… don’t have any bones! Their entire skeleton is composed of cartilage. That’s why they are called cartilaginous fish

… can fall into trance! If they’re turned upside-down, sharks fall into a state of paralysis and become perfectly still

… are among the oldest fish! The first appeared over 450 million years. They’re older than the dinosaurs!

… reproduce in different ways! Some species lay eggs, some carry eggs in their bodies until they hatch, and yet others give birth to live young, similar to mammals.

… include some species whose embryos attack one another while still in the womb! This is called interuterine cannibalism, and only the strongest young survive, while the others are eaten.

… include the largest fish species in the world — the whale shark

… don’t live exclusively in seas and oceans! Some species, such as the bull shark or several ray species can live in rivers or lakes, temporarily or indefinitely.

… can be pregnant for up to two years!

… possess a sixth sense! Sharks and rays have special organs called the Ampullae of Lorenzini, which can detect electric vibrations. Animals possessing such organs can find prey by sensing its heartbeat

… attack humans far more rarely than many other animals! Cows, hippos, mosquitos and dogs are just few among many species that attack humans far more frequently than sharks

… include some species that don’t ever sleep! Some species of sharks need to constantly keep swimming in order to breathe, and so can never sleep! They remain semi-conscious while they rest.

… can have up to 15 rows of teeth! The largest and strongest teeth are found in the first row

… do have scales! They are different from scales in other types of fish, and each consist of a tiny hook curved towards the animal’s tail. If you pass your hand over the shark’s body going from head to tail, it will feel very smooth, and very rough if you go in the opposite direction – from tail towards its head.

… can move both upper and lower jaw! In cartilaginous fish, the upper jaw is not attached to the skull, and can move independently of it

… don’t have a lot of predators, but humans present the greatest threat to sharks and rays! Over 100 million of sharks are caught each year, and that’s not including rays!

Back to Fascinating facts

(Visited 352 times, 1 visits today)