Answer to Question #131871 in Evolution for uzaima gul

Question

evolution of mamalian molar dentition in triasic period?

Answer 1

evolution of mammalian molar dentition in Triassic period

The Triassic period is the geologic period between the Permian and Jurassic period. This period came into being as a result of the mass extinction at the end of the Permian around 252 million years ago which eliminated about 70% of terrestrial vertebrates and the majority of plants found on land. As a result there was enaction of new much stable ecosystem that took about 30m years to establish.

The vanishment of the gorgonopsians which were the dominant predators of the Permian period paved way for rise of new prerdators the archosaurs that were the dominant carnivores; this developement is known as the Triassic period.

The gomphodont experienced a reduction in postcanine crown complexity, by loss of extra tooth morphologies and simplification of crests, cusps and cingula, consequentially developing a more complex interlocking mechanism between postcanines, larger occlusal surfaces by means of central occlusal basins, leaf-shaped or self-sharpening incisors, and optimized craniodental features for muscles for food processing.

This was the first clear evidence of a fully formed mammalian jaw joints and middle ears, in which the jaw joint is formed by the dentary and squamosal bones while the articular and quadrate move to the middle ear, where they are known as the incus and malleus.