It's Just a Giant T-Rex With Wings

Imagine a Giraffe.  Now imagine it had 30-foot wings.  Now imagine that it has none of the faggy qualities of a giraffe, and only the terrifying size of a giraffe.  Now imagine it's got teeth a foot long and razor sharp.  I know what you're thinking.  "Maybe I can run from it."  This motherfucker can fly 10,000 miles in one fucking journey.  In fact, most flights that this horrifying creature would take burned off an average of about 160 lbs in energy.  That's a human. 
See This?

Yeah, you know - that huge bird looking thing with a grown dinosaur in its mouth?  Thats a standard Pterosaur.  I'm talking about Giant Pterosaurs.
These collosal monstrosities could chase you across multiple continents. 
Look, I don't know what it is that end up doing the dinosaurs in, but I'm fucking glad it happened.