Major world events Flashcards
When did Earth form?
4.6 billion years ago.
How did Earth form?
Gravity coused debris to clump together and from the Earth.
4.5 billion years ago, what happened?
A planet crashed into Earth and created the moon.
form 4 billion to 3.8 billion years ago, what major event occured?
The Late Heavy Bombardment, when comets rained down on Earth and gave it water.
When did life first appear?
3.8 billion year ago.
What kind of life was the first life?
Anerobic single celled organisims.
When did Earth’s surface become solid?
3 billion years ago.
When did cyanobacteria appear?
2.5 billion years ago.
What did cyanobacteria do?
They photosythezied, putting oxygen into the atmosphere, which stated the Great Oxynagation event.
After the Great oxynagation event, what evnet happened?
Snowball Earth.
How long did Snowball Earth last?
From 2.5 billion to 650 million years ago.
Multicellular life emerged when?
550 million years ago.
