Earth's mass extinction - Peter Ward

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View full lesson: http://ed.ted.com/lessons/earth-s-mass-extinction-peter-ward Asteroid strikes get all the coverage, but "Medea Hypothesis" author Peter Ward argues that most of Earth's mass extinctions were caused by lowly bacteria. The culprit, a poison called hydrogen sulfide, may have an interesting application in medicine. Talk by Peter Ward.

Published 2013-02-01 · Watch on YouTube ↗
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