In a shocking new discovery, scientists have determined that Dinosaurs were neither warm blooded, or cold blooded, but "lukewarm" blooded. This means our conception of dinosaurs as big lizards is completely wrong.
Modern reptiles, like snakes, are cold blodded, which means that their body temperature is determined by the air around them. Birds and mammals, however, generate their own body heat, and have a regular internal temperature. For a long time there has been a debate between paleontologists as to which one of these the dinosaurs were.
According to a new study from the University of New Mexico, dinosaurs were mesothermic, which means a medium between warm blooded and cold blooded. This was discovered by looking at rings on the thigh bones from twenty one species of dinosaur including Allosaurus and the famous Tyrannosaurus. Much like trees, these growth patterns can be used to determine the rate at which an organism grows. It is an equation of growth versus energy intake, this relation provides the upward cap for species size, and is the reason animals don't grow as big as they did in the Triassic and Jurassic eras. This same equation works differently for mammals than cold blooded animals. Cold blooded creatures grew and moved slower than warm blooded creatures, and the growth rings in the thigh bones of dinosaurs suggest they were somewhere in the middle.
Very few creatures currently alive can eat enough to sustain this kind of hybrid system. Today very few animals have this type of metabolism. Such exceptions include the echidna, the great white shark and the leatherback turtle.
You know those dinosaurs that terrified you the first time you watched Jurrassic Park as a kid? In reality the T.Rex moved just as fast as Velociraptors. Now we know that they could live in more areas, eat more, hunt more, and were much faster than we ever imagined.