Timeline of the major events of the evolution of earth

Essay by lebinvasion June 2004

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408 - 360 million years ago streams. The variety of land plants increased dramatically and the first land animals appear. Tracheophyta, vascular plants, evolved along water's edge supporting a greater diversity of invertabrates like spiders and scorpions. Evidence supporting an episode of global cooling suggests that warm water marine species were the most severely affected when sea levels lowered triggered by a glaciation event on Gondwana.

360 - 286 million years ago The first reptiles evolve. Westlothiana, a tiny creature, contains many intermediate characters between primitive tetrapods and true amniotes.

286 - 245 million years ago The continental islands move together to form the massive landmass of Pangea. Ocean currents moderate temperate coastal areas, and the continental interior is dry.

245 - 200 million years ago The continental mass was warm, but cut off from rain-bearing ocean winds, inland regions formed vast deserts. In the seas ammonoids have replaced the trilobites of the Permian.

Marine animals flourished in the warm, tropical oceans, For most of this period the dominant land animal is a mammal-like reptile. Their posture was sprawling and their size was from one to three meters in length. Dinosaurs begin to evolve. In the late Triassic.

208 - 150 million years ago The rifting of the supercontinents continue. The Atlantic Ocean opens and shallow seas covered much of North America. Climates were warm and wet. The primitive dinosaurs which survived the extinctions at the end of the Triassic begin a 130 million year dominance of the planet. Primitive mammals, marsupials, and cranes have evolved.

149 - 65 million years ago Temperatures on Earth were warm. Flora and fauna thrived around polar regions. The land was covered with forests and a large inland sea divided the North American Continent. Over the next era the planet would warm again...