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Triassic

Triassic. Plants.

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Triassic

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  1. Triassic

  2. Plants Seed ferns like Glossopteris, ferns and early species of gymnosperms (seed plants, such as the evergreens, in which the seeds are not enclosed) dominate the Triassic terrain. Cycads , with tufts of tough, palm-like leaves and a woody trunk, appeared in the late Carboniferous and were abundant in the Triassic. Laurasia was dominated by conifers, other seed plants and ferns; Gondwanaland was dominated by

  3. Jurassic

  4. Animals It lived about 22 to 215 million years ago in the Late Triassic period. Its name means 'Flat lizard'.Plateosaurus belonged to a group of dinosaurs known as prosauropods which was related to the sauropods of the Jurassic and Cretaceous periods. Plateosaurus was a 9 metre long herbivore weighing about 4 tonnes. It was about 4 metres tall. It evolved in the Late Triassic period and lived up till the Early Jurassic period. It was the first of the giant dinosaurs to feed only on plants and the first to be able to feed on vegetation in trees by evolving a long neck. It had long back legs and a long tail. Its mouth was like a beak but had teeth. It walked on four legs but probably stood on its back legs and grabbed branches with the claws on its front legs as it fed on leaves. Palaeontologists believe that they may have lived in herds.

  5. Jurassic animalsThe dominant land animals were the huge dinosaurs, the largest land animals ever. They were the gigantic herbivore (plant-eaters) sauropods such as Diplodocus and Brachiosaurus. Other herbivores included Stegosaursaurus. Carnivorous (meat-eating) dinosaurs included Allosaurus and Dilophosaurus. The dinosaurs of the Jurassic were much more different from each other than in other periods: there was a greater variety. Because of the different climate, the forests grew, and the herbivores became huge in order to feed on the tall trees. The carnivores then had to become larger and more fierce to deal with such huge prey.The first birds appeared, such as Archaeopteryx. The seas were full of marine reptiles such as the plesiosaurs, crocodiles, ichthyosaurs, sharks and rays.

  6. Cretaceous

  7. Plants Imagine the time before the evolution of flowering plants, the time of the dinosaurs,  200 million years ago. The air is damp and smells of moist earth. The raucous cries of strange creatures reverberate through the jungle, and all around you are strange plants.  What kind of plants?  Jurassic plants -- Cycads.   Cycads, (pronounced si'kads), formed an extensive portion of the flora of that time, and no doubt the herbivorous dinosaurs grazed contentedly on the abundance. However, the dinosaurs disappeared, and so did most of the cycads -- except for a few incredibly resilient species that still cling tenaciously to existence today.  Now they are referred to as living fossils, for they have remained virtually unchanged, and give us a glimpse into a long-distant past.   Cycads are commonly mistaken for ferns, palms or bamboo but they are actually conifers, bearing conspicuous naked cones.  Comprising only 11 genera (Bowenia, Ceratozamia, Chigua, Cycas, Dioon, Encephalartos, Lepidozamia, Macrozamia, Microcycas, Stangeria and Zamia) and approximately 300 species, they are the rarest plants on Earth.  Cycads display a remarkable diversity.  Leaf size ranges from 8 inches in the diminutive Zamia pygmaea, to 23 feet in the gigantic Encephalartos laurentianus.  Leaflet colour varies from yellow-green, lime green, dark green, purple-green, to silver and even blue.  There are cycads with  arborescent (tree-like) trunks, and cycads with subterranean trunks.  Longevity and growth rate also varies by species; Zamias can mature and reach coning age in only three to five years, while other, larger species such as the Dioons can take decades to cone and may live to be 1,000 years old.

  8. . The Cretaceous period marks the end of The Age of the Dinosaurs.Big and small dinosaurs lived in great forests of cycads, conifers and ferns. There were great marine reptiles in the seas and great flying reptiles in the skies.Some things happened in the Cretaceous period that were important to life on earth. One of these was the development of flowering plants. By the end of the period, there were many that we would recognise today, such as magnolias and waterlilies. Animals

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