Question

What is earth's history?

Answer 1

Wow! How to summarize 4.5 billion years of events? A lot happened.

Explanation:

Here is a pic to get you going. You can also check out this site which has a cool little sliding tool to show you events over time.
http://exploringorigins.org/timeline.html

Here are the highlights:

1) Big bang produced the universe 13.6 billion years ago
2) solar system starts to form from a gas nebulae 4.6 billion years
3) Earth forms about 4.5 billion years and is shortly thereafter struck by a giant proto-planet - causes the moon to spin off and go into permanent orbit.
4) Oceans and atmosphere form about the same time.
5) first life forms around 3.8 billion years ago in the oceans
6) first photosynthesising algae start to pump oxygen into the atmosphere. Planet becomes oxygenated 2.5 Billon years ago.
7) first multi-cellular organisms evolve around 600 million years ago.
8) explosion of bivalves and trilobites in the oceans around 550 million years ago.
9) plants and first amphibians colonize the land - around 350 million years ago Vertebrates first evolve around this time.
10) the great dying event around 250 million years ago kills off 90% of species - super greenhouse event.
11) dinosaures thrive for over 135 million years - first small mammals evolve around 100 million years ago.
12) Dinosaurs killed by giant asteroid impact - 65 million years.
13 ) Mammals take over niches previously occupied by dinos.
14) first early primates and our ancestors evolve around 10 million years ago..
15) modern humans evolve around 200,000 years ago.
16) present day - humans start to have a major impact on the planet - land, oceans and atmosphere.