A great revelation swept over Robert Bakker one night dur ing his sophomore year at Yale University. As he walked through the darkened museum, faint bits of light caught the dinosaur skeletons and made them appear to move through the shadowed stillness. It occurred to Robert as he studied the familiar bones that these creatures had ruled the earth for 165 million years. They couldn't have been stupid, cold blooded and sluggish.
Intelligent mammals were around. They would have taken over unless the dinosaurs kept winning because they were fundamentally better. Robert Bakker set out, all alone, to prove that the prevailing view of dinosaurs was completely wrong. Bakker turned to four sources of information to de velop his case: comparative anatomy (comparing the size and shape of similar parts of different species), latitudinal zonation (where the animals live), the cumulative fossil record (all previously collected dinosaur bones and skeletons), and ecology (relationship of a species to its environment).
For three years Bakker exhaustively studied the bones of mam mals and found that they, as were dinosaur bones, were rich in blood vessels and lacked growth rings, just the opposite of cold blooded reptiles. He found that Cretaceous dinosaurs thrived in northern Canada where cold blooded reptiles could not have survived. Finally he studied African and North American ecosystems and found that warm blooded predators eat six to eight times as much per pound of body weight as do reptile predators. By studying the fossil record, Bakker found that the ratio of predators to herbivores in dinosaur ecosystems matched what would be expected of a warm blooded ecosystem. Dinosaurs had to have been warm blooded.Their bones, relative numbers, and locations proved it.
He studied the legs of zoo animals, comparing leg structure to how they moved. Did a chicken's leg bend differently than a zebra's? How did those differences relate to the different activity of each animal? How did form dictate function for each animal, and how did function dictate form? What did the shape of a dinosaur's joints and the size of its bones say
about how it must have moved and functioned? He tried to account for this motion and the implied probable muscle masses to control and move each bone in his drawings.
He compared leg bone size, shape, and density for hundreds of modern animals with those of dinosaurs. He found that dinosaur leg bones closely matched the bone structure of running mammals not those who sprint for 10 seconds when alarmed, but those who regularly run for 20 minutes.
Dinosaurs were runners. Their structure proved it. That also meant that they were agile. No sluggish, clumsy oaf would be a natural runner.
Bakker again turned to the fossil record and found that very few baby and juvenile dinosaur skeletons had been discovered. This meant that few died, which in turn meant that parent dinosaurs had to have been very successful at protecting, sheltering, and feeding their young. Dinosaurs were good parents.
The old myths were shat tered. Bakker published his findings while still a graduate student at Harvard. But it took another 20 years of intense data collection and analysis for the tide of belief to turn in Bakker's direction. Even after Bakker's discoveries revolutionized science's views of dinosaurs, he was still viewed with suspicion as an untrustworthy radical.
