Features of therapsids that suggest this group was transitional to reptiles and mammals.

Therapsids has both characteristics that possessed by mammals and reptiles.

For example :
The skull.  Therapsids skull is the combination between the skulls of reptiles (that have many several bones) , and the skull of mammals

The teeth. All The teeth in a reptile usually has the same sizes. But the occipital condyle in many therapsids became double just like in mammals

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