Random World Idea. Old West, Post-Apocalypse with Dinosaurs

[noob]

I do not think it is too odd to say that the temperature did raise to comparable values to the temperatures that existed during the varied dinosaur eras or that the modern dinosaurs were meant to handle the current climate(it is unlikely that the ones who made them had all the genetic code so completing it would have happened and changes like making them slower so that they use less food or making them able to handle the current climate would probably be good candidates).