The Paleozoic era ended with the P-T extinction - the Great Dying - when about 80-90% of marine life died, but more marginal survival rates were found on land. Dycodont therapsids (two tusked proto-mammals with reptile body plan and leg splay) , predatory amphibians, and diapsid reptiles (reptiles with advantageous openings on the skull, all modern birds and crocs have this for example) all survived to varying degrees. Into the Mesozoic reptiles would continue to adapt to a rebounding ocean seen in species such as ichthyosaur. On land, conifer trees began to take hold and mosquitoes evolved to become a pest for the next 230 million years.
This is all to say we don’t really know what any of these guys looked like, maybe like how this comic portrays, checks don’t fossilize unfortunately.
What’s a check?
American for a cheque. Something used by dinosaurs.
One single piece from a bowl of Chex Mix? Not sure why’d you sign it though. I’m not even confident Chex Mix existed when dinosaurs were around.
People still used checks in 2017?
Maybe, maybe not. But they did in the Mesozoic.