Going by the idea that current global warming is man-made, we must deduce that the dinosaurs had created enormous carbon footprints from their callous industrious methods that led to the thawing of permafrost 50 million years ago. Shame on them!
It was probably while they were building the pyramids that they had need of fire. You know, so they could see inside, and after dark. They probably burned old tires, which caused the global warming.