Chapter 30.2, Problem 2MI

Summary Introduction

To write:

Two facts about the subgroups of mammals.

Introduction:

Mammals are a group of vertebrate animals that have mammary glands present in females to produce milk for feeding. They have a backbones and hair or fur on their skin which helps in maintaining body temperature. They are generally warm-blooded animals.

Explanation of Solution

Mammals are divided into three different subgroups on the basis on how their babies develop. These are marsupials, monotremes and the placental mammals. Placental mammals is the largest group.

Marsupial animal’s babies feed from the mother and continue to grow inside the pouch of mother. Example: Kangaroos, Koalas, etc.

Monotremes are different from other mammals as their body temperature is lower than the other warm-blooded animals. Example: Platypus

A placental mammal develops inside the mother's body till the body systems able to perform function on their own. Example: Humans, lion, etc.

Two facts about the subgroup of mammals are:

1. Monotremes are mammals that lay eggs.
2. Marsupial mammals give birth to babies that are premature and very small in size.