Archaeothyris
Archaeothyris lived in what is now Nova Scotia, about 306 million years ago in the Carboniferous Period (Pennsylvanian). Nova Scotia was at this time a swamp, similar to today's Everglades in Florida. The 'trees' (actually giant clubmosses) were very tall. Some, such as Lepidodendron, were up to  tall. Archaeothyris and the other early amniotes lived on the forest floor.