LEC 1 - Earth's time scales

Question 1

Biological clock

Answer 1

Way to show and think about how much has developed in such little time
-> Humans enter barely before midnight

Question 2

When were the 5 extinctions?

Answer 2

all in phanerozoic
[palizoic(2)]
transition from permian to tarassic (96% life died)
[metazoic(trassic to jurasic)]
Transition from cretatious to Paleogene (dinos dead)

Question 3

When did the first life appear?

Answer 3

Archean

Question 4

When did o2 atmosphere appear?

Answer 4

Protezoiz (beginning)

Question 5

RNA World

Answer 5

The hypothesis of life origins

• > compounds of h2o combined to make a self-replicating RNA
• > YES this can happen, but how did cell membrane?

Question 6

Types of Earth’s atmospheres?

Answer 6

Primary -> First 0.5 billion years, made of He and H2
Secondary -> Volcanos formed, (archean), added h2s, created a reducing atmosphere, chemotrophs and anaerobes lived (proterzoic)
Tertiary -> photosynthetic cyanobacteria appear adding O2, aerobes dominate life

Question 7

species

Answer 7

go back to ecology notes LOL
Biological
ecological
phylogenetic species (DNA)