Having read the reviews, i would like to point out a few things.
1. While there were "small dinosaurs", small is a relative term. There were no dinosaurs I am aware of as small as a mouse or rat. I haven't see any evidence for dinosaurs as small as 1 kg (2.2 lbs).
2. Unlike birds, many species of mammals, even large mammals, under go hibernation. Hibernation would allow mammals to ride out a period of ecological disaster caused by a giant meteor strike. Many reptiles and amphibians can also under go extended period of inactivity. (Definition of hibernation was revised to include bears.)
Birds, with very few exceptions, do not undergo extended periods of inactivity (hibernation). If dinosaurs were like birds they too might not have been able to hibernate, so even small dinosaurs could be be hit hard by the massive meteorite strike. After a few months, plants might recovery, but dinosaurs it appear had high bird like metabolisms, but possibly no ability to undergo hibernation, and would starve to death, even small dinosaurs.
3. Birds greater mobility would allow them to find the few spots where the environment might have been spared, a sheltered valley or such, which allow them to survive. Even so, birds did not survive as well as mammals - only a few families of birds survived, some of them based on aquatic or seabird bird families.
4. Mammals survived better. The groups of mammals that survived were from much more widely diverse groups, Placental, Marsupial, Monotremes, and Multitubulars. The bird survival is more as if one family of mammals had survived, say Primates, and only certain branches of it at that.
5. Crocodiles are large, but aquatic, and in any case they can "aestivate" (their equivalent of hibernation).
6.Even if the absolute number of dinosaur species decline fore the K-T extinction, dinosaurs were a long, long way from becoming extinct. if not as common as they once were (and that is highly debatable), dinosaurs were still common and numerous overall up to the time of the extinction. Had the K-T extinction not occurred, presumably due the giant meteorite impact, there is no indication that the dinosaurs would have disappeared anyways in the next few million years, the fossil record doesn't support that.
