History of the Earth
Season 1, Episode 2: What Was Earth Like 4 Billion Years Ago?
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All Episodes - Season 1
Episode 1
How Did The Earth Form?
Episode 2
What Was Earth Like 4 Billion Years Ago?
Episode 3
The Mystery of the Late Heavy Bombardment
Episode 4
Where Did Earth's Water Come From?
Episode 5
How Did Life Begin?
Episode 6
What Was The Last Common Ancestor of all Life on Earth?
Episode 7
Were Volcanoes The Key To Life?
Episode 8
Did Life on Earth Come From Space?
Episode 9
What Would The Earth Have Been Like Without Life?
Episode 10
What is the Oldest Fossil on Earth?
Episode 11
How The Earth Got Its Magnetic Field (And Why It Might Not Protect Us Much Longer)
Episode 12
What Was Earth Like 3 Billion Years Ago?
Episode 13
How Bad Was The Great Oxidation Event?
Episode 14
How Did Life Recover From The First Mass Extinction?
Episode 15
What Would The Earth Be Like Without Photosynthesis?
Episode 16
What Was The First Virus?
Episode 17
What Is The Other 99.99% Of Life?
Episode 18
What Was The Earth Like 2 Billion Years Ago?
Episode 19
A Tour of Earth's Ancient Supercontinents
Episode 20
A Tour of Earth's Ancient Superoceans
Episode 21
What Was The "Boring Billion" Really Like?
Episode 22
What Was The First Complex Life on Earth?
Episode 23
What Was The Earth Like 1 Billion Years Ago?
Episode 24
What Was The First Fungus?
Episode 25
Why Did The Earth Totally Freeze For 100 Million Years?
Episode 26
Were These The First Animals?
Episode 27
How Far Back In Time Could You Have Survived On Earth?