Biostratigraphic dating

According to Smith and Keyser 1995, Gorgonops is known from the Tropidostoma and most of the Cistecephalus Assemblage Zones. The holotype is an incomplete and flattened skull found at Mildenhalls, Fort Beaufort, South Africa.

A number of other specimens have been found since, all from the Tropidostoma and/or Cistecephalus Assemblage Zone(s).

This was a medium-sized therapsid, with a skull about 22 cm in length.

It is distinguished from other species by a longer snout, and other details of the bones of the skull.

Aside from the teeth, one of the key predatory advantages that Gorgonops had over prey were that the legs supported the body from below rather than sprawling out to the sides like in most prey animals of the time.

Aside from allowing for more energy efficient locomotion, the legs would have also allowed for a much faster pace.

This gelogical time scale is based upon Harland et al., 1990, but with the Precambrian/Cambrian boundary modified according to the most recently-published radiometric dates on that interval, revising the boundary from 570 /- 15 million years to 543 /- 1 million years ago (Grotzinger et al., 1995).

Absolute time measurements can be used to calibrate the relative time scale, producing an integrated geologic or "geochronologic" time scale. [One of the earlier attempts at an integrated geochronologic time scale.] Obradovich, J.

It is important to realize that with new information about subdivision or correlation of relative time, or new measurements of absolute time, the dates applied to the time scale can and do change. ISBN 0-521-38765-5 [One of the more recent compilations of the entire geologic time scale.] Holmes, A., 1937.

Revisions to the relative time scale have occurred since the late 1700s.

earlier than the other species, most probably Pristerognathus Assemblage Zone) Synonyms: Pachyrhinos kaiseri (Broili & Schroeder, 1934) The holotype of the type species, Gorgonops torvus, was in 1876 one of the first therapsids described, by Richard Owen, who also coined the name "Dinosauria" on the basis of the first known dinosaur fossils.

It was also used as the type for which Richard Lydekker described the family in 1890.

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Perhaps the most distinctive features were two enlarged canine teeth that were so big (12-cm long) they almost protruded beyond the lower jaw.

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