Radio Ecoshock on "Catastrophism"

From Radio Ecoshock we hear Peter Ward, scientist, author, and the expert on past mass extinctions, and maybe the present one, who discusses "Catastrophism", the theory that extreme events determine the course of life more than the uniform process of evolution.

We are now in the 6th great extinction event. All previous ones, except an asteroid hit, were driven by climate change. Peter Ward has written the best theory so far on how these extinctions proceed -starting with a change in ocean life that produces a poisonous gas instead of oxygen.

With that in mind, we look at threats to plankton, with Canadian scientist Paul Beckwith. Some studies show plankton down by 40% world-wide, since 1950. Is it true?

Up to 70% of the oxygen you breath right now came from plankton. It is also the basis of all life in the ocean. We need to know.