Nova ….climate change earth science ..Nova has several programs on the knowledge network about this very issue and how life flourished on our planet .......pretty much all the oil ,coal natural gas we now consume was created during the carbonifous era .... we the stupid people just keep cutting down the rain forests.....the lungs of the earth ....no wonder we have global warming .....i,m afraid we are doomed in the long run as we keep over populating the planet .....even a big nuclear war will not stop the over population ....oh well ...enjoy it will it lasts ......