Animals like Seymouria are thought to be a midway between a amphibian and a reptile. Seymouria was small about 2 ft (60 cm) long.
The dry climate of the Permian suited reptiles better than amphibians and other more primitive tetrapods, but Seymouria had many reptilian features that helped it in this harsh environment. It had long and muscular legs, and may have had dry skin and the ability to conserve water.
Seymouria ate insects, small amphibians, and possibly eggs of reptiles.