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origin and evolution of species [3]click to hear

Since its formation some 4.6 billion years ago, the Earth has witnessed the genesis of continents and oceans and the appearance of animals and vegetation.
origin and evolution of species [3] Permian mesosaur dimetrodon Jurassic ichthyosaur archaeopteryx plateosaur Triassic nothosaur coelophysis megazostrodon

Permian click to hear

Geological period marked by the predominance of reptiles and amphibians. The continental mass now formed into a great protocontinent: Pangea.

mesosaur click to hear

First aquatic reptile with long sharp teeth and a powerful tail allowing it to propel itself in shallow water.

dimetrodon click to hear

Carnivorous reptile fossil with dorsal spines connected by a membrane to regulate its internal temperature; dominant in the Permian period.

Jurassic click to hear

Geological period during which the dinosaurs ruled the world. The Atlantic Ocean was formed at this time.

ichthyosaur click to hear

Swift carnivorous marine reptile; it had certain dolphin characteristics and reached 33 feet in length. It disappeared during the Cretaceous period.

archaeopteryx click to hear

Animal fossil capable of flight; it had certain characteristics of a reptile (claws, teeth, long bony tail) and others of a bird (wings, feathers).

plateosaur click to hear

One of the largest dinosaurs of the Jurassic period. This long-necked herbivore stood upright on its hind legs to reach the leaves of trees.

Triassic click to hear

Geological period marked by the breaking apart of the great protocontinent, the formation of today’s continents and the appearance of mammals.

nothosaur click to hear

Carnivorous amphibious dinosaur fossil with short finlike limbs adapted to move on land and in the water.

coelophysis click to hear

Two-legged carnivorous dinosaur, extremely agile and fleet of foot, with powerful claws.

megazostrodon click to hear

About the size of a mouse, one of the first mammals to appear on Earth was a mainly nocturnal insectivore.