Scientists Just Found the Cause of Earth’S First Global Warming That Triggered Mass Extinctions (Download PDF)

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When some of 1st worm-like creatures evolved at bottom of sea, they triggered wave of global warming that would lead to mass extinction. Based on limited fossil evidence available, that in following 100 million years mass extinctions would repeatedly strike Earth & its primitive inhabitants.

Image of Mass Extinctions

Image of Mass Extinctions

Image of Mass Extinctions

Process of First Global Warming

  • Around 500 million years ago, these animals began to burrow into sea floor, leaving fossilized burrows that are now only evidence we have for their existence.

  • Their wriggling movements mixed layers of organic material that was allowed to accumulate gradually w/o properly breaking down.

  • These tiny actions had big consequences, as disturbance of underwater sediments boosted breakdown of organic matter & brought about major environmental shifts.

  • As side effect it started using much more oxygen & producing much more carbon dioxide.

  • There was sharp decrease in oxygen levels at this point in planet’s distant past.

Use of Mathematical Model

  • After realizing role played by tiny creatures mixing up sediments, Scientists had found “missing piece of puzzle”. To investigate this idea, research team constructed mathematical model of Earth around that time.
Image of Use of Mathematical Model

Image of Use of Mathematical Model

Image of Use of Mathematical Model

  • Model showed that evolution of these small animals did indeed decrease oxygen in ocean & atmosphere, but increased atmospheric carbon dioxide levels to such extent that it caused global warming event. Results were published in Journal Nature Communication.

Significance to Modern World

  • As modern world gets warmer due to carbon dioxide being pumped into atmosphere, & areas of ocean lose their oxygen, scientists have warned we are currently living thru another mass extinction.

  • There is interesting parallel b/w earliest animals changing their world in way that was bad for them, & what human animals are doing to planet now.

  • While environmental changes are comparable, key difference is timescale over which they are taking place.

6Th Mass Extinction Underway

  • Many scientists think evidence indicates 6th mass extinction is under way.

  • Blame for this one, fastest in Earth’s history, falls firmly on shoulders of humans.

  • By year 2100, human activities such as pollution, land clearing, & overfishing may drive more than half of world’s marine & land species to extinction.

- Published/Last Modified on: September 17, 2018

Science/Technology, Geography

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