DEVELOPMENT OF THE PLANT AND ANIMAL KINGDOMS
The Palaeozoic era (570-230 million years ago), is divided into six periods: Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian. In the extensive oceans of this era the plant and animals kingdom developed and evolved. Many marine animals already had calcareous or silicic shells and skeletons. In the early Palaeozoic time, the first vertebrate animals evolved. By the middle of the Palaeozoic era, extensive parts of the land-mass had become colonised by plants and various species of fishes developed in the oceans. By the end of the Palaeozoic the first animals--vertebrates, began to leave the sea. These were amphibians. At the time-boundary between the Palaeozoic and Mesozoic, the single continent (land-mass) was split into two "super-continents" - Laurasia in the Northern Hemisphere and Gondwana in the Southern Hemisphere.
 
 

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The Mesozoic era (230-66 million years ago) covers three periods: Triassic, Jurassic and Cretaceous. By the end of the Cretaceous, both Gondwana and Laurasia had already begun to split up and the "plates" began to drift apart, on what are modern continental boundaries.

In the Mesozoic era, molluscs prevailed in the oceans, and bony fishes developed. Highly advanced reptiles gradually developed, among the largest of which were dinosaurs, achieving lengths of 30 m.

By the end of the Mesozoic, flowers, higher-order plants, and primitive birds and mammals began to the land. The warm, damp climate favoured the growth of tropical woods from the Equator to very high latitudes in both the Northern and the Southern hemispheres.
 
 

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The Cenozoic era (beginning 66 millions years ago and extending to the present time) covers three periods: Palaeozoic, Neogene and Anthropogene. During this era , the Atlantic and Indian Oceans expanded considerably, thus reducing the volume and area of the Pacific Ocean. The continents acquired their present-day outlines. The air temperature cooled gradually and the result was the development of mixed, deciduous forests and coniferous woods. In high latitudes, there was a zone of tundra. Mammals became the prevailing life-forms on the land. However, the most outstanding event came at the end of the Cenozoic era: the emergence of Man, the first living thing that has had an active effect on the future of life of the Earth.
 
 

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Information provided by HDNO:  http://www.oceansatlas.com/unatlas/about/ContactInfoForHDNO.html