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Related to Jurassic period: Cretaceous period
Jurassic period a period of the MESOZOIC ERA that lasted from 200 to 135 million years ago, during which time the birds evolved. Cycads, ferns and conifers were widespread. Dinosaurs were dominant and the first fossil moth was recorded from this period. Pangea began to break up and the site of London was at 30 °N.