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origin and evolution of species [1]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 [1] Ordovician agnathan orthoceras brachiopod Cambrian trilobite Precambrian cyanobacteria stromatolite

Ordovician click to hear

Geological period marked by the appearance of the first vertebrates and new marine invertebrates. Corals, sponges and mollusks were especially abundant.

agnathan click to hear

Jawless fish with a cartilaginous skeleton. Fish of this type still exist today (lamprey).

orthoceras click to hear

Aquatic invertebrate fossil with a shell and arms equipped with suction cups; it was the ancestor of the nautilus, squid and octopus.

brachiopod click to hear

Marine invertebrate fossil with a body protected by a bivalve shell.

Cambrian click to hear

Geological period marked by the evolution of animals (appearance of mollusks, crustaceans) and the extinction of half of the marine invertebrates.

trilobite click to hear

Marine invertebrate fossil with antennae and a carapace divided lengthwise into three lobes; it disappeared in the Permian period.

Precambrian click to hear

The oldest and longest geological era, marked by the formation of continents and the appearance of ocean life.

cyanobacteria click to hear

Blue-green algae, among the first living microscopic organisms to appear on Earth.

stromatolite click to hear

Stratified calcareous concretion formed by microscopic algae (stromatolites), testifying to the existence of the first life-forms more than 3 billion years ago.