QUOTE (WraithGod @ Apr 25 2008, 03:30 AM)

Well, it's not so much the literal size of the brain as the brain:body mass ratio. Tyrannosaurs had larger brains, but not proportionately, and proportion is what matters. If you were to add cerebral material it would only increase the size. If we're talking human-level intelligence, reptiles don't have much in terms of their brains that's dedicated to higher-level mental processing at all, so that would increase how much would have to be added. Even with sacral brains for the tail and limbs, a dragon's head would definitely not look like a crocodile's.
A croc brain is similar in proportion to a tyrannosaur's if I remember correctly, and there is a direct correlation between the brain-body ratio and intelligence. I'm going off memory here, but a human is 1:50, and though I don't have a crocodile's the closest dinosaur is Troodon at 1:500.
Can you show me some reading about the intelligence of crocodiles being greater than that of a horse? I'd definitely be excited if that were true, but I'd need to see several studies. Crocodiles may best other reptiles, but having them best mammals and birds is a huge jump. I'm sure crocodiles can learn classical conditioning cues, but what about operant? I've never seen a croc learn a trick as horses can.
Actually, Wraith, the brain:body mass ratio is important for mammals because: major motor control functions are centralized in the brain, and are linear. Larger bodies need more nerves to control them, the processing is located in the brain, and the nerves carry the information in a straight line to the muscles. This is a lot of wiring, and why intellegent mammals have to have big heads (even carnivores, cetatians, and elephants have a rounding of the cranium).
It's different for birds, reptiles, and presumably, dinosaurs. Much of the motor control processing is located in the spinal chord, freeing up space in the brain-pan (youv'e heard about chickens walking around with their heads cut off?). Reptiles typically use a motor-nerve system that is pyramidal. Essentially: a nerve for a leg fires off, then sends a cascade of signals to local leg nerves, and the whole leg moves. It is a highly efficient system, and it is no wonder that first won the size race (mammals having split off at the same time). So: more of the brain pan can be dedicated to other Functions: like sensory and analysis. And, so: the brain:body mass ratio is not a good rule of thumb for these species.
Examples: Crows are remarkably intelligent, and African Grey parrots have demonstrated in laboratory contritions the ability to differentiate number, kind, and color, simultaneously. Crocs routinely outsmart herbivorous ungulates, cooperate socially, have widely varied system of calls, and, can be taught "tricks" and recognize individuals. For all of their great memory, horses are pretty dumb when faced with a new situation, crocs are more adaptable. T-Rex may have had a big brain, but since almost all of it was devoted to massive scent processors, probably wasn't too bright. The pack hunting dinos, as well as opportunists, such as troodon, may have been far more intelligent than their brain ratios might indicate.
I'm not saying any of the species I went over approach human intelligence (something we measure poorly in ourselves), but there is a cultural tendency to dismiss the idea of any intelligence in other species.
PS: sorry for a biology heavy response in a religion topic. Prehaps we should have different threads to deal with different aspects of the subject.