Permian period

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Permian period

the last period of the Palaeozoic era which lasted from 280 to 240 million years ago. Amphibians declined in numbers, reptiles increased, and conifers became commoner during this period. Many extinctions occurred, including that of the trilobites. Mammal-like reptiles appeared and the first beetles, caddis and bugs evolved. The site of London was at 10 °N.