2. It is the slender loris found in the scrub jungles
of india.
It is a small (8 inches long) tail-less, slow
moving, nocturnal primate with a short, dense,
soft fur, large eyes and thin rounded ears.
Its color is earthy brown and it has a slender
build and lanky appearance. Its limps are thin.
The muzzle is white and nose projects beyond
the lower jaw.
3. It is omnivorous, feeding on fruits, leaves,
insects, eggs and birds.
L.malabaricus is slightly smaller and little a
darker, found in Malabar, Wynad, Coorg and
Travancore forests.
5. AQUATIC ADAPTATIONS
Various specialisations or adaptations are found in
the truly aquatic mammals. They are as follows
1. Large size
* The aquatic forms generally grow to a very huge
size. Whalebone whale grow up to 35 meters in
length and weigh about 150 tons.
*Large size reduces skin friction and heat loss.
2. Body shape
* In fish elongated head, indistinct neck, enlarged
flattened tail and tapering streamlined body offers
little resistance and swims rapidly through water.
6. 3. Paddles or flippers
Hind limp become completely reduced.
Fore-limps are transformed into paddles or flippers, in
which the skeleton fused internally and develops a skin
externally without any external indication of fingers and
toes.
The paddles serve as balancers and provides stability
during swimming.
4. Skin and its derrivatives
The skin loses its armour, hairs and glands.
In whales and sea cows, the hair is entirely lost except
for a few bristles around the mouth.
As a compensation for the loss of hair, the aquatic
mammals have developed a thick layer of fat known as
blubber in the cutaneous tissue beneath the skin.
7. FUNCTIONS OF BLUBBER
1. It act as a heat insulator i.e. it serves to maintain
the body temperature constant.
2. It also provides a ready reservoir of food and water
during emergency.
3. It reduces the specific gravity of the animals in
water.
4. It provides an elastic covering to allow changes in
blood volume during keep dividing and also
counteracts the hydrostatic pressure.
8. 5.Nostrils, pinnae and eyes
Nostrils are placed far back on top of head. So that
animal can breath air without raising head much out of
water.
Pinnae are absent.
Eyes are adapted to aquatic vision. In most cases they
are small and reduced.
6.Skeletal system
Bones are light spongy and are filled with the oil in
whales as an adaptation to reduce the weight of the
skeleton.
Cranium or brain case becomes shorter and and at
the same time higher and wider accommodate the
short and wide brain.
Ribs become arched dorsally and thoracic cavity
9. 7.Mammary glands
During lactation, ducts of mummary glands dilate to
form large reservoirs of milk which is pumped directly
into the mouth of young by the action of special
compressor muscle.
This facilitates suckling of young under water.
8.Digestive system
The jaws are useful to hold the prey and prevent its
escape. They have lost the power of mastication and
their muscle attachments are greatly reduced.
Teeth are simplified. They are monophyodont and
homodont in toothed whales.
Salivary glands are reduced but the stomach is
complicated with three or more chambers for crushing
and digesting the prey.
10. 9.Respiratory system
The external nostrils are valvular and can be closed
by valves during diving under water.
Lungs are large unlobulated and highly elastic. This
ensure taking and retaining maximum air before
submergence.
Oblique diaphragm makes thoracic cavity more larger
and provides space in the lungs for expansion.
10.Reproductive system
Testes are abdominal in position. They remain inside
abdomen.i.e they do not descend into the scrotal sacs.
Scrotal sacs are absent.
