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Sharks and rays

Sharks and rays are a unique group of marine vertebrates. Dr. Kathy Townsend explains more.

It is now time to introduce you to each of the different classes of marine vertebrates, starting with the sharks and rays.

Sharks and rays are in the class Chondrichthyes and include the Subclasses: Elasmobranchii (sharks and rays) and Holocepali (elephant or rat fish).

They are cartilaginous fish that contain over 1150 spp., and they can be found in marine and fresh water habitats.

Characteristics of Chondrichthyes include: jaws with teeth, a cartilaginous skeleton with paired fins, skin covered with denticles which are the same origin and composition as teeth, they have a large oily liver for buoyancy (instead of a swim bladder), and a heterocercal tail, which is long at the top and shorter bottom – which helps generate lift.

Having evolved millions of years ago, they are very well adapted for life below water.

Can you think of a famous shark or ray – other than Jaws? If so, pop your answer in the chat below.

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Life Below Water: Conservation, Current Issues, Possible Solutions

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