Surge in oxygen levels led to explosion of life: study

Surge in oxygen levels led to explosion of life: study

Context:

• Recently studies say that a boost in levels of oxygen may have caused a three-fold increase in biodiversity during between 445 and 485 million years ago.

Why is it in news?

• This study suggests that atmospheric oxygen levels did not reach and maintain modern levels for millions of years after the Cambrian explosion.
• In fact, the oxygenation of the atmosphere and Shallow Ocean took millions of years.
• And it was only when shallow seas became progressively oxygenated were the major pulses of diversification able to take place.

What has been found?

• Researchers were able to identify an oxygen increase during the Middle and Late Ordovician periods.
• They also found:
• 80% increase in oxygen levels where oxygen constituted about 14% of the atmosphere during the Darriwilian Stage (Middle Ordovician 460-465 million years ago) and
• Increased to as high as 24% of the atmosphere by the mid-Katian (Late Ordovician 450-455 million years ago).

The three fold increase:

• The explosion of diversity, recognised as the Great Ordovician Biodiversification Event, brought about:
• the rise of various marine life,
• tremendous change across species families and types,
• as well as changes to the Earth, starting at the bottom of the ocean floors.

Great Ordovician Biodiversification Event:

• The Ordovician radiation, or the great Ordovician biodiversification event (GOBE), was an evolutionary radiation of animal life throughout the Ordovician period, 40 million years after the Cambrian explosion.
• The distinctive Cambrian fauna fizzled out to be replaced with a Palaeozoic fauna rich in suspension feeder and pelagic animals.
• It brought about rise of various marine lives, tremendous change across species families and types, as well as changes to the Earth, starting at the bottom of the ocean floors.