The phytoplankton that brought Earth to life

Aired: 3/5/2014 | 0:04:43 | Clip
Without the "billion billion billion" Prochlorococcus, a plant-like bacteria in the ocean, Earth would not have the oxygen we breathe today. But the more scientists study about these diverse organisms, the less they know, says Penny Chisholm, an oceanographer at MIT.