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Lecture 19 Life of the Late Paleozoic Era. Historical Geology. Late Paleozoic Life. I Late Paleozoic Marine Communities II Late Paleozoic Land Communities A) Plants 1) Spore-bearing Plants 2) Gymnosperms B) Metazoans (Animals) 1) Reptiles 2) The Amniotic Egg
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Lecture 19 Life of the Late Paleozoic Era
Historical Geology Late Paleozoic Life I Late Paleozoic Marine Communities II Late Paleozoic Land Communities A) Plants 1) Spore-bearing Plants 2) Gymnosperms B) Metazoans (Animals) 1) Reptiles 2) The Amniotic Egg III The Permian Mass Extinction
Historical Geology Late Paleozoic Marine Communities
Historical Geology Late Paleozoic Marine Communities Phylum: Echinodermata Class: Crinoidea
Historical Geology Late Paleozoic Marine Communities Phylum: Echinodermata Class: Blastoidea Petremites
Historical Geology Historical Geology Late Paleozoic Marine Communities Productid Brachiopods • index fossils for the Permian period • spines were attached at raised bumps found on fossil shells
Late Paleozoic Marine Communities Fusulinids Historical Geology Kingdom: Protista
Historical Geology Late Paleozoic Life Plants
Historical Geology Late Paleozoic Land Flora
Historical Geology Late Paleozoic Land Flora Lycopsids Lepidodendron stem Lepidostrobus cone Baragwanathia Lycopodium
Historical Geology Late Paleozoic Land Flora Sphenopsids • Sphenopsids were segmented spore plants that also achieved giant sizes • Calamites, Annularia • Modern sphenopsids include “horsetails”
Historical Geology Late Paleozoic Land Flora The Advantage of Seeds
Historical Geology Late Paleozoic Land Flora Seed Ferns Glossopteris
Historical Geology Late Paleozoic Life Insects • Insects had appeared in Devonian time • Wingless forms • Insects underwent evolutionary radiation in Carboniferous time • Primitive winged forms (dragon flies) • Forms with folding wings
Historical Geology Late Paleozoic Life The Amniotic Egg
Historical Geology Late Paleozoic Life Reptile Evolution
Historical Geology Late Paleozoic Life Reptile Evolution
Historical Geology Late Paleozoic Life Reptile Evolution - Pelycosaurs • evolved from the protorothyrids during the Pennsylvanian • the dominant reptile group by the Early Permian • evolved into a diverse assemblage The herbivore Edaphosaurus The carnivore Dimetrodon
Historical Geology Late Paleozoic Life Reptile Evolution - Therapsids Moschops Dicynodon diverse, mammal-like reptiles originated in the Permian but survived into the Triassic period
Historical Geology Late Paleozoic Life Reptile Evolution - Therapsid Characteristics • small- to medium-sized animals • displaying many mammalian features • fewer bones in the skull due to fusion of many of the small skull bones • enlargement of the lower jawbone • differentiation of the teeth for various functions such as nipping, tearing, and chewing food • and a more vertical position of the legs for greater flexibility, • as opposed to the sideways sprawling legs in primitive reptiles
Historical Geology The Permian Mass Extinction Losses Species: 90-95%
Historical Geology The Permian Mass Extinction fusulinids bryozoans tabulate corals rugose corals porifera trilobites brachiopods crinoidea blastoidea gastropoda
Historical Geology The Permian Mass Extinction • Global Cooling (Glaciation • Marine anoxia began in Late Permian, extended through Early Triassic • Negative shift in d13C values at extinction level (continental and marine sections) • Age of massive Siberian flood basalts is same as extinction • Climatic warming and drying near extinction level • Rapid Sea Level Oscillations
Historical Geology The Permian Mass Extinction Deep-sea anoxic interval (Japan)
Historical Geology The Permian Mass Extinction d13C isotopic shift(Italian Alps)
Historical Geology The Permian Mass Extinction Siberian Flood Basalts Reichow et al. Science 2002
Historical Geology The Permian Mass Extinction Siberian Flood Basalts • 45 identified lava flows • 400m to 3,700m thick • Volume of 1.5 to 3 × 106 km3 • Duration of eruptions was only ~600 ky
Historical Geology The Permian Mass Extinction Climate Change • Change from meandering to braided river systems in South Africa and Urals • Reduction in bank-stabilizing vegetation • Widespread charcoal horizons, desert sedimentation, warm indicators in paleosols (China, Australia, Antarctica) • Abrupt change from Glossopteris- to Dicroidium-dominated floras (Australia)