An interesting example of the re-evolution of features once lost, arises in the case of the pangaloon. Its body is covered in scales, but these are not the conventional reptilian scales that were possessed by its archosaurian ancestors 200 million years ago. These scales are actually plates of keratin. The original scales were retained as the archosaur evolved into the primitive coelurosaur dinosaur. Then, as the ancestral coelurosaur developed and evolved into the arbrosaur, many of its scales evolved into insulating feathers.
The pangaloon, which is evolved from an arbrosaur that has reverted to a ground-dwelling way of life, has redeveloped a scaly armor from masses of fur fused together. Its ancestor's ground-dwelling habit evolved as the ants flourished and became widespread in the Oligocene. As the ants evolved then so did the ant-eating adaptations of animals like the pangaloon. The typical, long toothy jaws of the arbrosaur have been replaced, in the pangaloon, by a tubular snout, along which lies a long sticky tongue that can be thrust out to a distance greater than the length of the head. It can push its snout down ant burrows and lap up the ants that adhere to the tongue's stickiness. The middle claw of the forelimb has developed into a strong hook that can tear into ants' nests to expose their tunnels and chambers. The nostrils are high up on the face and can be closed for protection.