End Of The Ordovician Period

Science notes

Question: What happened in the 5 mass extinctions and how did the extinctions happen?

Ordovician-Silurian mass extinction
Third largest mass extinction
Most life was in the sea
86% of sea life went extinct
Trilobites died
Brachiopods died
Graptolites died
An ice age was blamed for this mass extinction
They think climate change was the cause for this
Fall in sea level
Messed up the chemistry of the oceans
443 Mya
End of Ordovician period
Start of Silurian period

Late Devonian mass extinction
3 quarters of all species went extinct
Reefs got a hard hit
Much of the sea bed became devoid of oxygen
Nothing could be near the sea bed except for bacteria
Could of been multiple extinction over several million years
Changes in sea level