Triassic period


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Triassic period

the first period of the MESOZOIC ERA, immediately following the PERMIAN PERIOD. It lasted from 239 million years BP to 200 million years BP and was the age of reptiles in which the DINOSAURS emerged. Horsetails, cycads, Gingko and conifers were common, ammonites reached their peak and the first primitive mammals and flies appeared. The site of present-day London was at 20 °N and Britain was moving northwards.