istory of life on earth - text breakdown
- History Of Life On Earth - Revision
- Archean
- Single celled organisms
- Lots of CO₂
- The sun was very faint
- Cambrian Period
- Explosion of Species
- Animals swam, crawled, burrowed and hunted
- The sea was the centre of living activity
- Ordovician
- Things started to explore the margins of land, but nothing got far
- There was a 500 000 year ice age in this period
- Everything was still confined to the seas
- Silurian
- The reefs got their act together
- They were not made of the same material as todays reefs, however
- Plants became more established on land
- Bony fish started appearing
- Devonian
- This is known as the age of fishes
- This is because we see many new fishes start appearing over here
- Seas were around 30º celsius
- There were more than 365 days in a year
- Carboniferous
- The highest oxygen levels the Earth has every seen
- Plants grew and died at such a rate, they eventually became coal
- The first reptiles appeared here
- There was an ice age at the end of this period
- Permian
- The largest mass extinction happened in this period
- There one large continent called Pangea
- Pangea was arid
- Oxygen plummeted too
- Triassic
- Heat, vast deserts, warm seas
- Life took a while to recover
- The first mammals and dinosaurs are seen here
- Jurassic
- The first birds and some dinosaurs
- Breaking up of the continents
- Cretaceous
- The most famous mass extinction happened here
- Sea levels were very high
- India began its journey North, forming the Indian Ocean=
- Paleocene
- Evolutionary experiments
- Mammals and birds became more distinguished
- Dense forests
- India collided with Asia
- The climate was much wetter and sea levels rose
- Eocene
- This was a time of global warming
- Forests thrived everywhere, even at the poles
- India pushing against Asia formed the Himalayas
- Africa began its journey upwards an collided with Europe to form the Alps
- Oligocene
- This was a time of global cooling
- Grasslands became larger and forests shrank correspondingly
- This allowed for the development of fast running prey and predators
- Miocene
- The apes arose and diversified during this epoch
- Human ancestors and the ancestors of the chimps had split up
- Kelp forests made their first appearance
- Grasslands carried on to grow
- Pliocene
- The human lineage had split away and formed over here
- Ice at the North Pole became permanent
- Pleistocene
- This was a period with punctuated Ice Ages
- Our species evolved here
- Holocene
- This is the current epoch
- All of these time periods fall under larger time blocks
- Eon
- Phanerozoic
- Cenozoic
- Mesozoic
- Paleozoic
- Proterozoic
- Archean
