Another sketch I did for the Mesozoic graphic novel idea a long time ago, featuring Cynognathus (intended to be the main characters) and Kannemeyeria. This was meant to help establish the environment, although I never ended up colouring it.
The sketch is meant to show the arrival of the polar winter heralding the end of the prime feeding season. The herds of large herbivores are fleeing north, while smaller burrowing animals are preparing to hunker down in preparation for the long darkness ahead, and ginkgo trees begin to shed their leaves and go dormant.