Re: One problem...
My thought is that this is around the time that grass evolved. It would have been outcompeting the shrubs and ferns that predominated the food chain and would have caused major changes in the fauna that fed on it. This could only have continued with more time and put large pressures on the dinosaur populations. It is likely they would have (mostly) gone extinct anyway. The meteor just ruled a line under them.
Biting the hand that feeds IT
