This looks like a pretty interesting book, hot off the press (Today!) from Princeton University Press:
What Bugged the Dinosaurs? Insects, Disease and Death in the Cretaceous. 2008. George and Roberta Poinar.
From a press release:
“The authors argue that insects provide a plausible and effective explanation for the slow, inexorable decline and eventual extinction of dinosaurs over many thousands of years….“We don’t suggest that the appearance of biting insects and the spread of disease are the only things that relate to dinosaur extinction,” Poinar said. “Other geologic and catastrophic events certainly played a role. But by themselves, such events do not explain a process that in reality took a very, very long time, perhaps millions of years. Insects and diseases do provide that explanation.”
“In dinosaur feces, we found nematodes, trematodes and even protozoa that could have caused dysentery and other abdominal disturbances. The infective stages of these intestinal parasites are carried by filth-visiting insects.”
In the Late Cretaceous, Poinar said, the world was covered with warm-temperate to tropical areas that swarmed with blood-sucking insects carrying leishmania, malaria, intestinal parasites, arboviruses and other pathogens, and caused repeated epidemics that slowly-but-surely wore down dinosaur populations. Ticks, mites, lice and biting flies would have tormented and weakened them.”
I’m not sure I buy this, but it is a neat idea. I’m looking forward to seeing their evidence.
You may recognize these authors from The Amber Forest, an earlier book.