The answer to this question is really not what the OP suspects , but the fact is there are creatures living on the Earth that predate homosapien and have existed unchanged since the time of the dinosaurs. If these creatures had not survived, they would definitely have been classified as 'dinosaurs' ;crocodiles and komodo dragons are two examples, So the answer is simple, men and dinosaurs do coexist and have since men have been on this planet.