Earth's Geological time eras by Addison Roberts

Precambrian Time

addisonroberts4 — 2024-02-13 14:45:55 UTC

The Precambrian encompasses nearly 90% of the history of the Earth and around a third of the history of the Universe. The Precambrian begins with the formation of the Solar System 4.57 billion years ago (bya) and extends to the beginning of the Cambrian 540 million years ago (Mya, or 0.54 bya).

What are 5 major events that happened during this time?

addisonroberts4 — 2024-02-13 15:04:23 UTC

Consider that the Earth formed, life arose, the first tectonic plates arose and began to move, eukaryotic cells evolved, the atmosphere became enriched in oxygen -- and just before the end of the Precambrian, complex multicellular organisms, including the first animals, evolved.

Palezoic Era

addisonroberts4 — 2024-02-27 14:50:58 UTC

Paleozoic means 'ancient life. ' The oldest animals on Earth appeared just before the start of this era in the Ediacaran Period, but scientists had not yet discovered them when the geologic timescale was made.

What are the 5 periods of the Paleozoic Era?

addisonroberts4 — 2024-02-27 14:52:12 UTC

The Paleozoic is divided into six periods: the Cambrian, Ordovician, Silurian, Devonian, Carboniferous (in the U.S., this is divided into the Mississippian and Pennsylvanian Periods), and Permian. Most of these names derive from locations where rocks of these ages were first studied.

Mesozoic Era

addisonroberts4 — 2024-02-27 14:53:35 UTC

The Mesozoic Era (251.9 to 66.0 million years ago) was the "Age of Reptiles." During the Mesozoic, Pangaea began separating into the modern continents, and the modern Rocky Mountains rose. Dinosaurs, crocodiles, and pterosaurs ruled the land and air.

What is Mesozoic Era known for?

addisonroberts4 — 2024-02-27 14:54:19 UTC

The ancestors of major plant and animal groups that exist today first appeared during the Mesozoic, but this era is best known as the time of the dinosaurs.

Cenozoic Era

addisonroberts4 — 2024-02-27 14:55:12 UTC

Cenozoic (66 million years ago until today) means 'recent life. ' During this era, plants and animals look most like those on Earth today. Periods of the Cenozoic Era are split into even smaller parts known as Epochs, so you will see even more signposts in this Era.

What is Cenozoic Era known for?

addisonroberts4 — 2024-02-27 14:55:32 UTC

The Cenozoic spans only about 65 million years, from the end of the Cretaceous Period and the extinction of non-avian dinosaurs to the present. The Cenozoic is sometimes called the Age of Mammals, because the largest land animals have been mammals during that time.