Chapter 27, Problem 10TY

Summary Introduction

Introduction:

Prototherian is derived from the Greek word ‘Protos’ means ‘first’, and ‘therios’ means ‘beast’.

Prototherians are very ancestral forms in the Mammalia (Class) and Prototheria (Subclass). The animals of prototherians are only egg-laying that’s why they are oviparous. Most of the prototherian mammals are extinct. They are reptile-like and highly primitive mammals.