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Artists interpretation of a Lower Permian swamp in Texas (Williston, in Shimer)

Plate Tectonic Reconstructions

The Permian* was a time of specialization for marine fauna, with major diversifications of ammonoids,  brachiopods  and bryozoans. A slab exhibiting some of the richness of this fauna is on display. Insects, amphibians, reptiles, and therapsids (the precursors of mammals) flourished during this time. The Permian is the last Period of the Paleozoic Era. It ended with the greatest mass extinction known in Earth's history. More than 95% of all species disappeared from the fossil record, with many families, orders, and even classes becoming extinct.  Among the animal groups suffering major extinctions were the trilobites, rugose and tabulate corals, blastoids, placoderms and pelycosaurs. Other animal groups suffering extensive reductions included the brachiopods, bryozoans, ammonoids, crinoids, sharks, bony fishes, euryptids, ostracodes and echinoderms.  A variety of spore-bearing plants also became extinct. The extinctions were spread equally across terrestrial and marine environments.

All of the continents remained fused together in the supercontinent Pangea during this Period, which moves to the north. The climate began cool and humid with a carboniferous type of flora. It then transitioned to a warm and arid regime favoring more modern plant types that could colonize the dry land as sea levels fell. There was a dramatic loss of coal swamps and amphibian habitats.

*The Permian was named in 1841 by Murchison in collaboration with Russian Geologists for the beds lying above Carboniferous strata in the ancient Kingdom of Permia and the city of Perm in the Ural mountains of Russia.

Permian Animal (Metazoan) Fossils
Trilobites (ToL: Trilobites<Arthropoda<Ecdysozoa<Bilateria<Metazoa<Eukaryota)
	The Permian saw the last of the trilobites: none survived the great extinction event. Specimens of individuals of two species and an assemblage of a third are displayed: Delaria sp. Ditomopygie sp. Kaskia sp. assemblage.
Vertebrates (ToL: Chordata<Deuterostomia<Bilateria<Metazoa<Eukaryota)
	Extinct amphibians are well represented in the Permian fossil record. Permian amphibians were generally large, such as the 5-6 ft. long Eryops represented by a skull cast in our display. However, there were also small species, such as the salamander-sized specimen of Branchiosaurus in this case. Eryops skull cast Side view Front view Inside roof of mouth, showing palatal teeth restoration of live animal Branchiosaurus - Apateon sp.
	Reptiles (Reptilia) have an abundant fossil record in this period. The display includes: A slab with small reptile footprints, A mounted specimen of a lizard sized Captorhinus aguti, a member of the extinct captorhinids (Captorhinidae<Romeriida<Reptilia). These primitive reptiles were a closely related sister-group to the diapsids (Diapsida<Romeriida<Reptilia), which includes birds and all modern reptiles other than turtles. A close-up image of the skull is also provided for this specimen. A cast of Permian reptile egg. Unlike amphibians, reptiles were able to move away from bodies of water due to their desiccation-resistant eggs. A small, very complete mesosaur, Mesosaurus braziliensis (Mesosauridae<Anapsida<Reptilia) Image of fossil High Res image of fossil restoration of live animal.
Brachiopods (ToL: Brachiopoda<Lophotrochozoa<Bilateria<Metazoa<Eukaryota)
	Brachiopods were an important part of the marine fauna for the last time during the Permian, bordering on extinction ever since. Multiple specimens of three species represent brachiopods in this display: Cleithytidina orbiscularis (Three specimens, each about 1/2 inch diameter, multiple views showing characteristics) top view side view valve view Hustedia mormoni (Three specimens, each about 1/2 inch diameter, multiple views showing characteristics) top view side view valve view Composita sp. (Three specimens, each about 1 inch diameter) Unidentified brachiopods (some indicated with arrows) on assemblage slab.
Moss Animals (ToL: Bryozoa<Lophotrochozoa<Bilateria<Metazoa<Eukaryota)
	The reticulated fan-shape objects (arrows) on this slab are moss animals or bryozoans.
Corals (ToL: Cnidera<Metazoa<Eukaryota)
	Cnidarians (corals): The horn (rugose) corals, such as these examples of solitary coral, and the tabulate corals disappeared forever at the end of the Permian.
Foraminiferans (ToL: <Protozoa<Eukaryota)
	The small (rice-grain size, some indicated by arrows) objects all over this slab are fusilinide foraminiferans, a colonial protozoan which make spiral, rice-grain shaped shells of calcium carbonate.
Permian Plant Fossils
Vascular Plants (ToL: Embryophytes [land plants] <Green Plants<Eukaryota)
	Pteridospermophyta (seed ferns) are represented by a slab with leaves from Glossopteris sp. and Gangmopteris sp. and a second slab with Glossopteris sp. alone.
	Conifers readily colonized dry land and increased their abundance during this time. They are characterized by their reproduction via cones. Two specimens of fossil branches and foliage are displayed: Lebachia piniformis and conifer sp.

The engravings are from Dana, James D. (1870) Manual of Geology, Le Conte, Joseph (1898) A Compend of Geology, Grabau, Amadeus (1901) Guide to the Geology and Paleontology of Niagra Falls, Shimer, Hervey Woodburn (1914) An Introduction to the Study of Fossils, or Pirson, Louis and Charles Schuchert, A Text-Book of Geology. (1920).

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Last modified 25 March 2008 | ©1998, HSU NHM