[dinosaur] Agressive behavior of the T. rex

Good day to all listmembers!



Just a short question - given the apparent agresivity of the Tyrannosaurus 
rex (adult individual), but also the fact, that human would be too small a 
prey for it - would it be perhaps "safe" for us to stand near it? In other 
words, if T. rex had a choice of attacking human some 20 yards away and a 
subadult 1 tonne Edmontosaurus 100 yards away, which one would it choose? 
Was there some size/mass limit for an animal, at which it would be not 
interesting as a prey item for an adult T. rex (or any other large theropod,
for that matter)? Thank you in advance! Tom