Childrens Illustrated Encyclopedia

HammerHead

The eyes and nostrils

of the hammerhead

shark are on the two

“lobes” of its head.

Hammerheads prey on

stingrays, unharmed by

the poison in their spines.

a perfecT sHape for speed, an incredible sense

of smell, and a mouth brimming with razor-sharp

teeth make sharks the most fearsome fish in the

sea. sharks have existed for 350 million years,

and their basic shape has hardly changed at

all during this time. as adults, they have no

predators and fear nothing in the ocean.

The great white shark is the largest predatory

fish, at more than 27 ft (9 m) in length and

2.7 tons in weight. dozens of huge teeth line

its jaws. The great white shark prowls the ocean,

eating any kind of meat, alive or dead, and often

swallows its prey in one gulp. sharks have to keep

moving in order to take in enough oxygen, and

the great white travels more than 300 miles

(500 km) in a day. although most fish have bony

skeletons, sharks and their relatives, the rays, have

skeletons made of a substance called cartilage.

rays are flat-bodied, with a wide mouth on

the underside and blunt teeth for

crushing clams and other

shellfish. rays live close to the

seabed and move gracefully

by flapping their huge wings.

461

THresHer sHark

This shark measures

20 ft (6 m) in length. It

lives mainly in the warm

coastal waters of the

atlantic and pacific

oceans but sometimes

strays north in summer.

fIn

a shark’s

dorsal (back)

fin cuts the sea’s

surface as the shark circles before

attacking. The dolphin’s fin is

more crescent-shaped.

Sharks’ teeth have a

serrated edge so they

can saw through flesh.

Shark

tooth

Huge

wings

Dorsal fin

Pectoral fin

Upper lobe of

caudal fin (tail)

TeeTH

sharks have many rows of

teeth. as they grow, the

teeth move from inside

the mouth to the outside

edge, where they are used

for tearing flesh. eventually

the teeth wear away or break

off, only to be replaced by the

teeth behind.

The thresher shark

lashes the water

with its tail to

sweep fish into a

group. Then, with

its mouth open,

the shark charges

through, gobbling

them up.

Stingrays have a poison

spine on the tail.

Good sense

of smell for

hunting

skIn

shark skin is covered with

toothlike scales and has

a texture like sandpaper.

Long tail used for

rounding up fish in

the water

Sharks and rays

sTIngray

There are about 100

kinds of stingrays—the

biggest measures 12 ft

(4 m) across.

Whale shark

The harmless whale shark cruises

slowly through the tropical oceans,

feeding by filtering tiny floating

animals (plankton) from the water.

It is a peaceful creature and is the

biggest fish of any kind, at 50 ft

(15 m) long. Nostrils are excellent

at detecting the smell of

blood in the water.

swImmIng macHIne

The shark’s swimming power comes from its tail. The larger upper lobe drives

it down with each stroke and helps keep the body level; otherwise the

creature’s weight would tilt its head down. a shark cannot swivel its

fins to stop quickly. It must veer to one side instead.

A human can swim safely with the gentle whale

shark, the biggest fish in the sea.

Excellent

eyesight for

spying prey

Dorsal fin

Find out more

animal senses

animals

fish

ocean wildlife

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