Here is one that was especially fun to draw.  The dinosaur-like creature in the third panel is inspired by the tooth fossils of Helicoprion (a prehistoric shark).  To this day, scientists are still not sure about what it looked like or how the teeth were set into the jaw even though the first fossils were studied over a century ago.  But there are a lot of imaginative artists who have come up with their own idea of how this shark was built.  Helicoprion sounds a lot like Helicopter.  The upper jaw of our illustrated monster is more similar to the one on Sarcosuchus aka the Super Crocodile.  The name means “Sarcophagus Mouth”.  Well not exactly, but anything caught in that thing’s jaws probably would be thinking something similar to that.