Asian Diver – March 2018

Anal fin

Second

Dorsal Fin

PROMINENT DORSAL FIN
Most sharks have a prominent dorsal fin
that is located on top of the animal behind
the head. This fin is often seen breaking
the surface and it plays a vital role in
propulsion, buoyancy and direction

LARGE LIVER
Most fish have a swim bladder that they fill with air to help control
their buoyancy but sharks rely instead on a large, oil-filled liver
to reduce their overall density and provide some measure of
hydrostatic lift

PECTORAL FIN
Like most fish, sharks have two pelvic fins
behind the head, but these are rigid,
not flexible, often elongated and are used
for buoyancy and steering

Stomach

Liver

Pancreas

CARTILAGINOUS SKELETON

Unlike other fish, sharks’ bodies contain

no bones and their skeleton is made of

cartilage. This material is considerably less

dense and more flexible than bone, making

sharks lighter and more agile. Sharks

use forward movement to control vertical

position. In most species, the tail acts as the

shark’s propeller while the pectoral fins are

used for balance and direction

LATERAL LINE
A visible line along the side of the shark’s
body consisting of sensory organs that
help to detect movement and vibration in
the surrounding water, providing spatial
awareness and the ability to navigate