How did the first life form? Flashcards
1
Q
First evidence of liquid water
A
4.4 Ga - during the Hadean eon
2
Q
Thermophiles
A
Thermophiles have a deep ancestral history, indicating that life formed/evolved while the earth was very hot
3
Q
“Organic soup” model
A
H2, CO2, CH4, NH4+, H2O, energy → life
4
Q
Pool drying model
A
molecules and structures brought close together when water evaporated, then pool filled back up
5
Q
When is the first evidence of life from?
A
Measured stable carbon isotopic composition (𝛿13C) consistent with life at 3.8 Ma but no reliable fossils until 3.5 Ma
