Never underestimate moss. When the simple plants first arrived on land, almost half a billion years ago, they triggered both an ice age and a mass extinction of ocean life. So...get out of the garden now and call Al 'Global Warming' Gore!
(New Scientist). The first land plants appeared around 470 million years ago, during the Ordovician period, when life was diversifying rapidly. They were non-vascular plants, like mosses and liverworts, that didn't have deep roots. About 35 million years later, ice sheets briefly covered much of the planet and a mass extinction ensued. Carbon dioxide levels probably fell sharply just before the ice arrived – but nobody knew why.
Now Tim Lenton of the University of Exeter, UK, and colleagues point the finger at mosses and liverworts as the culprits!
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| You see all you Save Planet Earthers: Planting more green things will get you this! |

