Wouldn't it be evolutionarily disasterous for a dromie (raptor) to attack large, carnviorus prey like a healthy T.rex (like all to many people have excitedly suggested)? I mean unless they were eusocial, attacking a large carnviore like Tyrannosaurus could be extremely bad for passing on your genes. And isn't four "raptors" and unusual number of attackers to lose for attacking a single Tendontosaurus? Has the pack-attack-unfeasibly-large-prey theory been taken to its illogicla limit? (I've heard some people saying the dromies actually killed off every dinosaur around and flew away in UFOs they constructed!!!)
from Honkie Tong, age 17, ?, ?, ?; July 25, 2001

TOM: It would be disastrous for a dromaeosaur to attack a healthy adult T. rex, indeed. They may have indeed preyed on the hatchlings and juveniles, but an adult would be way out of their league. Keep in mind that the dromaeosaurs of the latest Maastrichtian Epoch (the last four million years of the Cretaceous, when T. rex was alive) were all very small: smaller than a human being.

The fact that Deinonychus lost a number of individuals in what some interpret as an attack on Tenontosaurus is intriguing. If true, it may highlight one of the more important aspects of dinosaur biology: they weren't mammals!! All the non-avian dinosaurs seem to have been able to lay a dozen or so eggs a year, giving them a much greater rate of replacement than placental mammals. In fact, while the gestation period (and hence rate of replacement) of placental mammals increases with increasing body size, the rate of replacement of dinosaurs is independent of size. Thus, dinosaur populations could (and in fact must have) had lower rates of survival of individuals and still were viable. In other words: In the Mesozoic, Life was Cheap!

Although the UFO idea is obviously not a scientific one, it reminds me of a science fiction short story from the late 1970s (maybe earliest 1980s) by Barry Longyear called "The Homecoming". In it, it turns out that the troodontids (saurornithoidids at the time) had developed technology, had been wandering the galaxy, and came home surprised to find humans here. What was nice about the story was that it wasn't a shoot-'em-up, alien invaders story, but a compassionate story for both the humans and the dinosaurs. One humorous bit was when the troodontids were asking what creatures of the Late Cretaceous humans had evolved from. The humans show them their idea of an early tree shrew-like protoprimate, and the dinosaurs said "oh yes, we remember those. They were very tasty."