Life during the Permian Period was very diverse—the marine life of the period was perhaps more diverse than that of modern times. The gradual climatic warming that took place during the Early Permian (Cisuralian) Epoch (298.9 million to 272.3 million years ago) encouraged great evolutionary expansion (diversification) among both marine and terrestrial faunas that had survived the relatively cold conditions of the Carboniferous Period. Many lineages entering Early Permian times with only a few species and genera progressively diversified into new families and superfamilies as the climate warmed. Communities became increasingly complex, and generic diversity (diversity of organisms at genus level) increased through the midpoint of the Middle Permian (Guadalupian) Epoch (272.3 million to 259.9 million years ago). Within the tropical shallow-water marine communities, significant environmental changes occurring at the end of the Middle Permian Epoch were so abrupt that many groups became extinct, and only a few of the remaining groups survived into the Late Permian (Lopingian) Epoch (259.9 million to 252.2 million years ago).
Terrestrial life in Permian times was closely keyed to the evolution of terrestrial plants, which were the primary food source for land animals. The fossil plant record for the Early Permian Epoch consists predominantly of ferns, seed ferns, and lycophytes (a group of vascular plants containing club mosses and scale trees), which were adapted to marshes and swampy environments. A less abundant Middle and Late Permian fossil record of early coniferophytes (a group of vascular plants containing cycads, ginkoes, and gnetophytes) and protoangiosperms (precursors to flowering plants) suggests a broad adaptation of these plant groups to progressively drier areas.
Evidence of broad plant diversification also is found in the rapid evolution of insects, which quickly followed plants into new habitats. As these insects adapted to their new surroundings and formed very specialized associations with plants, many new species emerged. Permian insects included at least 23 orders, 11 of which are now extinct.
Terrestrial life in Permian times was closely keyed to the evolution of terrestrial plants, which were the primary food source for land animals. The fossil plant record for the Early Permian Epoch consists predominantly of ferns, seed ferns, and lycophytes (a group of vascular plants containing club mosses and scale trees), which were adapted to marshes and swampy environments. A less abundant Middle and Late Permian fossil record of early coniferophytes (a group of vascular plants containing cycads, ginkoes, and gnetophytes) and protoangiosperms (precursors to flowering plants) suggests a broad adaptation of these plant groups to progressively drier areas.
Evidence of broad plant diversification also is found in the rapid evolution of insects, which quickly followed plants into new habitats. As these insects adapted to their new surroundings and formed very specialized associations with plants, many new species emerged. Permian insects included at least 23 orders, 11 of which are now extinct.
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