Archaeopteris

400 million years ago, there were no dinosaurs, there were no mammals, there were no birds, there were no flowering plants.

The land was colonised by the earliest forests of primitive, spore-bearing trees, Archaeopteris watiesa.

And the largest animals on land were arthropods, insects, and their relatives.

crawling through the leaf litter of a world that would be unrecognisable to any modern observer.