1st Extinction
The Ordovician Era
443 million years ago 85% of all species went extinct Reasons: An ice age“ followed by a rapid warming
2nd Extinction
The Devonian Age
374 million years ago 75% of all species went extinct Reasons: Fluctuating sea levels, altering global cooling and warming, drop in Co, concentration and periods of low oxygen
3rd Extinction
The Permian Age
250 million years ago 95% of all species went extinct Reasons: An asteroid hit the planet, filling the air with pulverised particles, leading to inhabitable climate conditions
4th Extinction
The Late Triassic Age
200 million years ago 80% of all species went extinct Reasons: Some colossal geological activity in the today's Atlantic Ocean that resulted in high CO,, global warming and acidified oceans
5th Extinction
Cretaceous Period
65 million years ago 76% of all species went extinct Reasons: Meteor crash in the Yucatan peninsula in Mexico, high volcanic activity
6th Extinction
The Holocene Epoch
About 99% of the planet's species have been lost in the previous five mass extinctions
Ongoing
Reasons: Anthropogenic factors like climate change and introduction of invasive plant species
This story is from the March 16, 2022 edition of Down To Earth.
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This story is from the March 16, 2022 edition of Down To Earth.
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