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Animal senses 25-
All AnimAls Are AwAre of their surroundings. Touch, smell,
taste, sight, and hearing are the five senses that animals and humans
use to detect what is happening around them. some animals,
however, have an array of senses very different from ours. A
dog’s nose is so sensitive to odors that it “sees” the world as a
pattern of scents and smells, in the same way that we see light
and color with our eyes. many creatures, particularly fish,
can determine where they are by picking up the tiny
amounts of bioelectricity produced by other living
things around them. A fish also detects vibrations
in the water using a row of sense organs down
each side of its body, called the lateral line.An animal’s senses, like its body shape,
are a result of evolution and suit the
animal’s needs. eyes would be of little
use to a creature such as the cave
fish, which lives in endless darkness.
instead, these creatures rely
on other senses such as smell
and touch. some senses
are extremely specialized.
long, feathery antennae
enable a male emperor
moth to “smell” the
odor of a female moth
3 miles (5 km) away.Dog follows a
scent with its
nose very
close to
the ground.Bloodhound
Bloodhounds have been
specially bred as tracker dogs.
Their sense of smell may
be as much as one million times
sharper than a human’s
sense of smell. Bloodhounds
can even detect the microscopic
pieces of skin that are shed
from a person’s body.The Bloodhound’s sense
of smell is so sharp
that it can even pick
up scent that is
several days old.The otter’s scenting organs
can detect many scents in
the air. These special organs
lie inside the nose in the
roof of the nasal cavity.Whiskers are sensitive
to touch. They also
respond to vibrations,
so they are useful in
murky water.The skin and hair roots
bear sensors that detect
vibrations, light touch,
heavy pressure, and
heat and cold.The otter hears
by sensing vibrations
when they strike its
eardrums. To help the
otter balance, tiny
fluid-filled canals
inside the ear work
like miniature levels
to register gravity.oTTer
while the sea otter floats on its back in the water, eating a shellfish,
its sense organs continuously send information about its surroundings
to its brain. The organs include the eyes, ears, nose, tongue, whiskers,
fur, skin, and balance sensors. stretch receptors in the joints and
muscles also convey information about the otter’s body position. The
smell of a poisoned shellfish or the ripples from a shark’s fin instantly
alert the otter to possible danger.Claws and soles of feet
are sensitive to touch.hunTing
senses
A shark can smell
blood in the water
hundreds of yards away.
As this shark closes in for the attack, it makes use
of its sharp eyesight and electricity-sensing organs.Lips detect sharp pieces of shell
in food and then spit them out.Sensitive forepaws
manipulate food.
The otter also uses
a stone to crack
open shellfish.A clear lens at the front
of the eye focuses rays
of light into the back of
the eye to produce a
sharp image.US_025_Animal_Senses_1.indd 25 20/01/16 4:32 pm