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Peter Ward: Earth's mass extinctions (TED)

submitted by notarobot

1 decade 5 years 9 months 3 weeks ago

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.

www.ted.com