ERAS

4 Billion- 570 Milion years ago

250 Million- 66 Million years ago

541 Million- 252 Million years ago

Began approximately 2.58 million years ago and continues to the present day.

Began approximately 66 million years ago and continues to the present day.

Precambrian Time

TIMELINE: GEOLOGICAL ERAS

Paleozoic Era

QUATERNARY

Mesozoic Era

• Formation of Earth.
• First simple life forms (bacteria and algae).
• Formation of the tectonic plates and primitive oceans.
• Earth’s crust solidification.

• Cambrian Explosion (rapid diversification of life).
• Development of marine life, first fish, and land plants.
• Formation of Pangaea supercontinent.
• Mass extinction at the end of the era.
• Recession of the seas.

CENOZOIC ERA

• Age of Reptiles (dominance of dinosaurs).
• First birds and mammals.
• Breakup of Pangaea.
• Mass extinction at the end of the era (including dinosaurs).
• Sinking of big land masses creates basins.
• Earth's crust streches.

• Age of Mammals (dominance of mammals).
• Evolution of primates and humans.
• Formation of modern continents and climate.
• Collisions among plates give rise to mountain ranges.
• Subduction causes the rise of the Oriental and Occidental Sierra Madre.

• Homo Sapiens evolution period and dominance.
• Evidences of a great glacial era.
• The subsequent thaw caused the sea level to rise between 30 or 40 meters.
• Widening of the continental shelf and creation of shallow seas.