Early Jurassic

What happened during this time?

• Gondwanan floras start to resemble northern continents

  • Equatorial groups became more prominent in Gondwana: Bennettitales, Conifers (e.g. Cheirolepidiaceae), Leptosporangiate ferns, such as Dipteriaceous, and Matoniaceous ferns, Ginkgoales and Czekanowskiales mostly absent from Gondwana, and Podocarp conifers prominent in Gondwana

• Cordaites, gigantopterids, and glossopterids no longer dominate

• Five distinct vegetative biomes exist by  this time (Rees et al. 1999)

  • Cool temperate

    • Low diversity of flora: 70 genera, 120 species

    • High proportion of deciduous and seasonal plants with growth rings

      • Dominated by ginkgoes

      • Macrophyllous conifers

        • woody and herbaceous members of Pinaceae and Voltziales 

      • Ferns

      • Equisetophytes

  • Warm temperate: below 60 degrees latitude and centered on 40 degrees

    • High in diversity

    • Ferns

    • Equisetophytes

    • Macrophyllous cycads

    • Macrophyllous conifers

      • woody and herbaceous members of Pinaceae, Taxodiaceae, Podocarpaceae

    • Ginkgoes were less common; first appearance of the genus Ginkgo

  • Winterwet

  • Subtropical desert

  • Summerwet tropical