Late Triassicearly Jurassic

Mammals are known from a number of Upper Triassic and Lower Jurassic sites, mainly in Western Europe, but also in Greenland, China, Africa, India, and North America (possible mammals ofthis age are represented in South America only by footprints). Collectively, these sites span the Carnian through the Liassic or possibly later. Although the faunas differ in composition, they share broad points of taxonomic similarity. Owing to this similarity and to the fact that they are collectively separated from well-known Middle Jurassic (Bathonian) assemblages by a substantial hiatus, it is convenient to treat them together. During the Late Triassic-Early Jurassic, the continental landmasses were largely united into the supercontinent Pangaea. Faunal continuity among regions that are now geographically disparate is indicated by the fact that many of Earth's terrestrial vertebrates—therapsids, mammals, dinosaurs, and others—are remarkably similar, often at the level of genus.

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