To big, Too old, Have you ever meet one. If so then send a pic otherwise you are lying and just being fooled by the government into thinking they are real like the rest of the sheep the truth is out there you just need to look for it, Man.
What are your reasons. They were very real. If they were not how could animals like the blue whale exist as there body plan paved the way for future animals. Also birds are dinosaurs they evolved from them and if you manipulate a birds genes it would look like a dinosaur.