Dentitions, Tooth-Replacement and Jaw Articulation

Abstract

Reptiles evolved into mammals under two separate pressures. The first was to improve hearing, so that they could become efficient nocturnal animals. This will be discussed in a later chapter (Chapter 6). The second pressure was dental: the unremitting drive to improve the efficiency of the teeth, initially for seizing and killing prey and later for cutting it up into conveniently sized pieces for swallowing. It will be noted that throughout we shall be talking about carnivores, as plant-eaters have such specialised dentitions that they have lost the capacity for further major advances. The future lay with the flesh-eater, and in particular with the insectivore with its relatively generalised dentition.