Wednesday, 3 July 2019


Fossil Field Trip / Ankylosaur Trackway
After an exciting hike in the dark through the woods and down a steep incline, we reached the river. The tracks in this photo are from a type of armoured dinosaur that dates from around 97 million years ago in the Late Cretaceous.

Imagine a meandering armoured tank munching on ferns, shrubs and low-growing vegetation as the grasses we picture in fields today had yet to evolve en masse. Their time would come about 30 million years later. We've found grass-like phytoliths (related to modern rice and bamboo) in the poop (coprolites) from Cretaceous dinosaurs.

There are three types of footprints at the Wolverine River site, the meat-eating theropods (at least four different sizes), the slow, lumbering plant-eating ankylosaurs and duck-billed dinosaurs. Bones from an Acrocanthosaurus, a meat-eating theropod have also been found in the area. These bad boys lived in the Aptian, in the Early Cretaceous and known from a single species, A. atokensis.

The trackway you see here was made by one of those armoured lumbering ankylosaurs and a few of the prints carry skin impressions. Filling the prints with water and using lamplight was genius for viewing tracks as they are all but invisible in the bright sunlight by day.