Pelycosaur

Cotylorhynchus (background), and Ophiacodon Varanops.

  • North America
  • Europe
  • South Africa

As Pelycosaurier ( Pelycosauria ) the primitive synapsids of the late Palaeozoic be called. From them therapsides ( Therapsida ) emerged, the ancestors of mammals ( Mammalia). The latter two groups are classically distinguished from the Pelycosauriern, so those are a Paraphylum.

The Pelycosaurier had a reptilian appearance; they possessed elongated body and moved in Spreizgang. Some of the biggest possessed among them sail back, which consisted of skin covered with spinous and gave them a dragon-like appearance. These sails were probably well supplied with blood and helped the animals as in the regulation of body temperature: When the morning the sun appeared, the cooled during the night animals would have without the sail used to take hours to become active again can; other hand, the sail could also be made with the edge to the sun and used for cooling.

The best known and largest Pelycosaurier are Dimetrodon ( " two types of teeth "), a 3.5 m large carnivores, and herbivores Edaphosaurus, of about the same size. They lived in the Early Permian, about 280 million years ago. In Erstgenanntem at least approaches to the development of various teeth are visible, but he still has a typical reptilian lower jaw, consisting of three bones. Smaller Pelycosaurier had to a large extent needed no sail and also had none, as up to about 4 m long Ophiacodon.

In any case, one can direct lineage of the Pelycosaurier on the therapsids to mammals and thus attract to us. With the much later living dinosaurs, however, the Pelycosaurier are not closely related. Later Pelycosaurier how the carnivores Wagontia from the South African Permian, are also classified among the early therapsids.

System

Carboniferous Mya (unit) Fossil
640869
de