[dinosaur] Would non-avian dinosaur survive through the whole Cenozoic?

Good day,



in his book "Dinosaurs Rediscovered", professor Mike Benton states that even
if non-avian dinosaurs survived the K-Pg event, they would probably 
eventually perish some 50 or 40 million years ago (due to climatic changes 
and/or other perturbations). This is because of their limited ability to 
evolve new species in the last millions of years of the Cretaceous. What do 
you think about this? Thank you very much! Tom