"Without people there to destroy the vegetation in building houses and killing the animals for food,the plants would get very large and so would the animals. The larger the animals had to get to reach the top of the plants, the more the CO2, and both plants and animals put off a great amount of heat. From the large pools of oil and coal, we know that there were places where there was a lot of plants and a large number of animals - like at a watering hole. So that tells me that if you want to cut down on CO2 build up - don't let a lot of plants and a lot of animals hang out together." (link to source, currently comment #12)
The fun part is, the trolls and pundits are going hard at each other in the comments, so this might not even be the worst fail to be found there. I chose this one because it is not overtly political, and it is fails on so many levels. Where to begin? Zoology fail, Biology fail, Ecology fail, Geology fail, time-scale fail ... It's all good.
Finally, a shout out to my friend NS at Science and Math Defeated. Thanks for the link, and back at ya!
See Science Fail #1.