At least four other early Permian creatures carried equally extraordinary display sails on their backs. (dinosaur factory)A distant relative of Dimetrodon was Edaphosaurus (“earth lizard”), a small-headed, barrel-bellied reptile, up to eight feet long, that preferred swampy habitats. Edaphosaurus evolved its fin totally independently of Dimetrodon and even featured extra ornamental devices knobby crosspieces sticking out sideways from the long spines. Edaphosaurus itself had a close relative with simple spines.
Permian amphibians were hardly upstaged by the skeletal theatrics evolved among the finback reptiles. The amphibians evolved an outstanding finback of their own. (life size dinosaur)A strong-legged, three-foot-long amphibian, Platyhystrix (“flat-spine”), evolved a dorsal display piece every bit as baroque as the edaphosaur’s. Just as with Dimetrodon, Platyhystrix had close relatives that hadn’t evolved such a crest. A single quarry at Rattlesnake Canyon, Texas, has pro duced specimens of Platyhystrix, Edaphosaurus, and Dimetrodon.(animatronic dinosaur) What was so special about Early Permian times that they should have produced so many giant dorsal displays in such profusion? No one knows.
The Golden Age of the finbacks is, however, a sobering discovery for scientists who believe in the principle of extreme uniformitarianism. This theory insists that evolutionary processes work the same way at all times. (dinosaur costume)But there has never been another age of finbacks to compete with the Early Permian. And why this episode in the evolution of body organization should have remained unique is one of the great unsolved mysteries in the history of life.