Question

a) Discuss in detail the differences between marsupial and placental mammals b) Describe the Marsupial orders of mammals in detail.

Answer 1

a) Mammals are divided into three groups.They are placental,marsupial and monotreme.

1. Marsupials offspring are born in embryonic stage.They remain in the mother's pouch until they complete their development.This pouch is located on the surface of their mother's body.

Placental mammal completes embryo development inside the mother.

It is the main difference between marsupial and placental mammals.

2. Marsupials have more teeth than placental mammals.They don't have milk teeth.

Placental mammals have less teeth than marsupials and they have milk teeth and adult teeth.Milk teeth replaced by adult teeth at certain age.

3 Marsupials have 35 degree centigrades body temperature.

Placental mammals have 38 degree centigrades body temperature.

b). Marsupialia is divided into seven orders.

1. Didelphimorphia:It has only a single family.It has 87 species and 17 genera.Opossums and mouse opossums are examples of this order.

2. Paucituberculata:It is an south american marsupial.It has 60 extinct species.

3. Mircobiotheria:It encompasses two families.It has only one extant species.

4. Monte:These are small nocturnal marsupials.

5. Dasyuromorphia:It has most of the australian carnivorous marsupials.It has 23 genera and 71 species.

6. Peramelemorphia:These are known as bandicoots and bilbies.They are live in Australia,New guinea or few islands.

7. Notoryctemorphia:They live in the deserts of central australia.They have short tails and pointed heads.