Interval of geologic time, 206–144 million years ago, that is one of the three major divisions of the Mesozoic Era , preceded by the Triassic Period and followed by the
During the Jurassic, Pangea began to break up into the present-day continents. Marine invertebrates flourished, and large reptiles dominated many marine habitats. On land, fern s, moss es, cycad s, and conifer s thrived, some developing flowerlike structures in place of cones. The dinosaur s rose to supremacy on land, and by the end of the Jurassic the largest species had evolved. {{link=archaeopteryx">Archaeopteryx , the first primitive bird, appeared before the end of the period. Early mammals, tiny shrewlike creatures that appeared near the close of the preceding Triassic, managed to survive and evolve.