geological eras

Paleozoic

542 BCE

• At the end of this era, the seas receded, what will give rise to future deserts.
• Pangea starts to break down.
• Life existed predominantly in the sea: invertebrates, jellyfishes, worms, mollusks, snails, and corals dominated the oceans.
• The first vertebrates appeared

Precambrian

541 BCE

It started approximately 4 billion years ago when the Earth’s crust started to solidify because of the rain’s action on the hot rocks. The oceans where the habitat of the first unicellular organisms and of the first oxygen-producing organisms, which started to modify the dense atmosphere composed mainly of methane, hydrogen and carbon dioxide

Mesozoic

252 BCE

• Pangea continues breaking down and the Earth’s crust stretches.
• This causes the sinking of big land masses and the creation of basins.
• North America and Eurasia were created

cenozoic

66 BCE

• Antarctica was definitively separated from Australia.
• The expansion of the North Atlantic Ocean moves Greenland away from North America.
• Collisions among plates give rise to mountain ranges in Asia, Europe and South America, i.e. the Himalayas, the Alps and the Andes respectively.
The Pacific Plate subduction causes the rise of the Oriental and Occidental Sierra Madre.

quaternary

25 BCE

• Glacial era started at the beginning of the Quaternary period.
The subsequent thaw caused the sea level to rise between 30 or 40 meters
• The Homo sapiens has been dominating the Quaternary