To end this year, 2012, best animal to learn that the prehistoric Pentaceratops. It could be any other, nothing would happen, but this is a little special. Basically, the reason that I consider this animal special, not because I have three horns and call Pentaceratops (5 horns), but because it is the largest land animal with the head of the whole story.
If someone calls you "big head" is because they do not know the Pentaceratops. An animal with a head of up to 3.5 meters (12 ft). A strong neck muscles full of robust bones embedded in supporting a large skull with a bone covered with thorns wheel and 2 meters (7 ft) in diameter. This collar bone was a formidable protector and a dominant male signal.
The Pentaceratops was taller and thinner the triceratops, less heavy, but a little higher. With strong legs, almost 6 tons, as a male African elephant, and 8 meters (26 ft) long. It, like other ceratopsians, was an herbivore and gregarious. With its enormous beak similar to a parrot, tore branches and bark to eat.
The Pentaceratops lived around the Campanian, Late Cretaceous 75 million years ago. Therefore triceratops existed before and not had to face with T.Rex. However, if you had the predator to Daspletosaurus or Acrocanthosaurus.
By the way, we see its curious name: your name means five horns and really have 3 is because it had two great apophysis (build bone) protruding from their cheeks. Views with meat, muscle and skin, these bumps closely resemble the bumps of the warthog.