Department of Zoology at ANDC/Zoology Museum/Museum specimens/Mammalia

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Class Mammalia

Date & Time : 17, October 2017 04:14



General Characteristics of Mammalia

  • Warm blooded animal.
  • skin is covered by hairs.
  • external ears (pinnae) are  present.
  • teeeth are heterodont.
  • skull with two occipital condyles, and no prefrontals, postfrontals and quadrato-jugal.
  • The lower jaw is composed of single bone on each side.
  • the digits are not more than five digits.
  • Heart is 4- chambered
  • Red blood cells are non - nucleated.
  • viviparous.

Classification of Mammalia

A Few Examples

1. Sorex

Common name-Shrew.

Distribution-found in Asia, Europe and North America.

Habit and habitat-lives in tunnel

Food- insects, worms and mice.

IDENTIFYING CHARACTERS-

  • Body- Rat like, and is covering with fur.
  • Body length-12.5 cm including the tail.
  • Body color- brown and pale.
  • elongated snout while eyes and ears are small.
  • Teeth-red in color, lower canines are absent and first pair of insisors is long.

      Dental formula is 

                                      i      3/2

                                      c     1/0                                 =32

                                     pm  3/1

                                      m   3/3

  • Limbs- limbs are consist of 5 clawed-digits.
  • It eat food twice as much as food as their weight. Shrew can not live withoout food more than ten hours.                           

2. Erinaceus

Common name- Hedge hog

Distribution- found in North India.

Habit and habitat- nocturnal in habitat, lives in holes.

Food- insects, worms, slugs, fruits and roots etc.

IDENTIFYING CHARACTERS-

  • Body-  back and sides are covered with spines but the ventral surface is covered with soft fur. 
  • Mouth- tubular.
  • Eyes and ear- small, but pinna is present which is also very small.
  • Teeth- 36 in number.

           Dental formula is 

                                       i     3/2

                                      c     1/1

                                     pm   3/2

                                     m     3/3         

  • Ribs- fourteen or fifteen.
  • Tail- it is very short. twelve rib is present in the tail.
  • The animal has the habit of rolling itself into a ball when it seems to be in danger.

3. Scotophilus

Bat.jpg

Common name- bat

Distribution -cosmopolitan in distribution

Habit and habitat- nocturnal in habit.i.e. sleep in day and comes out in night in search of their food.

Food- blood of other animals.

IDENTIFYING CHARACTERS-

  • Body- short in size.
  • integument- covered with  soft fur.
  • Snout- short and no nose leaf.
  • Ear- ear with large pinna providing with flags. high power of hearing.
  • Eyes-small, rods are not properly developed therefore, vision is very weak.
  • Teeth- molars have transverse groove.
  • Limbs-in the forelimbs , only thumb is clawed. but in hindlimbs, all digits are clawed.
  • Tail- it is included in the inter femoral membrane consistinfg of  a flap.
  • It likes to livein colonies.
  • When it strike to any object, it produce ultra sonic sound waves.

4. Talpa

Common Name- short tailed mole.

Distribution- found in the central and western Himalayas and Assam hills.

Habit and Habitat-burrowing animal, lives underground in burrows.

Food- earthworms etc.

IDENTIFYING CHARACTERS

Body-cylindrical.

Integument- covered with silky fur.

Head- short and conical.

Eyes- very small.

Teeth- 40 in number.

Limbs-fore-limbs are well developed, consisting of claws.

Ear- pinnae are absent.