Sharks have lightweight skeletons made of cartilage - a kind of rubbery gristle - rather than bone. Like most other fish, sharks have gills for breathing. However, unlike bony fish, which have a flap of skin over their gills, sharks have separate gill slits or openings. All sharks possess specialized teeth that are replaced through their lifetime, and skin covered with small, interlocking, tooth-like scales called denticles.

What is a shark?

Close relatives

Inside a shark

Ancient sharks

Amazing grace

Making sense

Laying eggs

Live young

Teeth and diet

Friend or foe?

The great white shark

Gentle giants

Basking beauties

Angel sharks

Horn sharks

Head like a hammer

Weird and wonderful

Shark artefacts

Shark attack

Sharks at bay

In the cage and out

Studying sharks

Tagging sharks

Shark overkill

Use and abuse

Save the shark!

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Glossary

Index