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origin and evolution of species [1]

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] Geological period marked by the appearance of the first vertebrates and new marine invertebrates. Corals, sponges and mollusks were especially abundant. Jawless fish with a cartilaginous skeleton. Fish of this type still exist today (lamprey). Aquatic invertebrate fossil with a shell and arms equipped with suction cups; it was the ancestor of the nautilus, squid and octopus. Marine invertebrate fossil with a body protected by a bivalve shell. Geological period marked by the evolution of animals (appearance of mollusks, crustaceans) and the extinction of half of the marine invertebrates. Marine invertebrate fossil with antennae and a carapace divided lengthwise into three lobes; it disappeared in the Permian period. The oldest and longest geological era, marked by the formation of continents and the appearance of ocean life. Blue-green algae, among the first living microscopic organisms to appear on Earth. Stratified calcareous concretion formed by microscopic algae (stromatolites), testifying to the existence of the first life-forms more than 3 billion years ago.

Ordovician

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

agnathan

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

orthoceras

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

brachiopod

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

Cambrian

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

trilobite

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

Precambrian

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

cyanobacteria

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

stromatolite

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