2013-02-01

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TED-Ed

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.