The First Land Animals - Footprints in the Stone
(Photo credit: Gerald MacKenzie) Earliest Carboniferous tetrapod tracks from Blue Beach (Nova Scotia, Canada) are found on more than 80 stratigraphic levels within the deposit. These 'track-bearing' layers of sandstone/siltstone/shale are exposed along several kms of shoreline, and are constantly revealed by the erosive force of twice-d aily tides in the Bay of Fundy. (photo credit: Christopher Mansky) Most of the footprints are preserved as 'undertracks', meaning they are from 'lower levels' than the ones' traversed by these creatures. Very few finds represent the 'actual track level' of the trace-maker, so most of the footprints display incomplete footmarks at best, and may be difficult to recognize until one becomes accustomed to the peculiarities of track preservation. Todays' example is an undertrack from one of the better layers, and shows nearly-complete foot morphology. (Photo credit: Christopher Mansky) The p...