Paleobiology is the division of paleontology that deals with fossil animals as living beings. Among other things, it is their job to determine how these prehistoric animals behaved. These scientists only have a few clues to work with, fossils being the most important, but they also have living animals to study and hopefully can fill in the blanks with logic and reasoning. Here are some of the clues that paleobiologists are using to determine dinosaur behavior.
Teeth and Jaws
Teeth are very telling because they can indicate what a dinosaur ate. Serrated or pointed teeth, that do not meet each other when the jaw is closed, indicate it was a meat eater. Flat, or rounded-off teeth set in a jaw built for grinding, indicate plant eaters. The build of the jaw suggests how muscles were attached, which indicates the power of the bite. What a creature ate determined much of its daily behavior. Plant eaters had to spend many hours eating, and digesting. Meat eaters had to find food too, but a good find could sustain them for a long time.
Most meat eaters were built for speed, designed to hunt, their heads held high to look for food. Most plant eaters were quadrupeds (with some exceptions of course). By studying the build of an animal the Paleontologist can make a guess as to how it behaved to a limited degree. The build of an animal naturally determines how it moves and what speeds can be attained.
Eggs and Nest Sites
Several fossilized nesting sites have been found, some with eggs, and youngsters. This teaches us about how the dinosaurs parented their offspring. These sites show that at least some dinosaurs did parent their young to a certain extent and lived in groups with all age ranges of animals present. Finds of this kind resulted in one Dinosaur being named “Maiasaura” or “good mother”. Unfortunately, what these sites do not tells is how the animals selected their mate. Were they monogamous, were matings random, or did one male lead a group of females?
Some fossil beds have shown a massive number of animals died and were buried at the same time (often by floods) we can see in these cases what dinosaurs lived in groups.
Many individual fossil footprints have been found. These are interesting, but it is the trails, or trackways, that are very telling. They can show which dinosaurs likely traveled together, in herds, and which ones traveled alone. They can show if the animals were moving with any speed, and tell a tale, giving us a small, but exciting, window into the past. Fossilized footprints have shown that dinosaurs very likely could swim.
Other Features in the Fossilized Bones
Some animals have large head crests, or bony growths on their back, some have spikes on their tails. What were these features used for and how did they impact behavior? Some dinosaurs have thick skulls, we can presume these were to protect their brains in head butting rituals for breeding rites, much as some animals alive today have thick skulls for this reason. There are still a slew of questions the paleobiologists are still trying to agree on answers for.
Small Brain Size
Since dinosaurs had relatively small brains for their overall size, they are considered “stupid”. Animal behaviorists suggest that stupid animals act in predictable ways. Additionally by looking at crocodiles, who seem to have limited intelligence, we also see that they form distinct social orders, it is very likely dinosaurs did the same.
By studying how current, yet primitive, animals behave, scientists can make better guesses at how these magnificent ancient animals behaved. The best providers of clues have proven to be primitive bird species and reptiles.
Putting it together and fixing mistakes
Originally the first fossil hunters thought dinosaurs were slow moving animals, we now know this is not true, many were terrifically fast. We also use to think they did not have any social skills among themselves, another fact we now have amended because of new fossil discoveries.
We know some things had to happen, dinosaurs had to mate, they had to reproduce, they had to spend a lot of time eating, or avoiding being eaten, and they did this for many, many, generations, millions of years to be sure. The tough part is filling in the blanks. With ongoing studies, and new fossil finds, paleobiologists are coming closer to determining how dinosaurs lived and behaved.