Dinosaur Communication
Paleontologists are increasingly confident that dinosaurs were probably able to communicate with each other. Some of the communication may have been "verbal" or noise, and some of this communication was probably of a "non-verbal" nature or what is called a visual display.
Some hints of the abilities for communication in dinosaurs come from their closest extant relatives: birds and the reptiles classed as crocodiles (which loosely includes alligators). The communication methods employed by these two dinosaur relatives include noise (both birds and crocodiles), and in the case of birds, plumage or body ornamentation. Everyone knows that birds can sing, warble and chirp. While crocodiles have a much smaller range of sound, than birds, they can emit deep sounds that can heard over great distances. In either case, the verbal communication is normally used to help locate mates or to warn of impending danger from predators.
Birds also communicate visually. The fossil record that has been able to be pieced together indicates that dinosaurs likely had reasonably well developed brains and very good eyesight. Recent fossil finds suggest that many dinosaurs may have had a coat of feathers. Some fossils are so well preserved it is possible to see patterns on the feathers themselves. The fact that the feathers were colored and patterned suggests that this plumage and other anatomical features were not only useful for keeping dinosaurs warm but also served some role in attracting mates. This is a characteristic of some modern birds that have very colorful and sometimes outlandish plumage that is used to impress mates. This would be an example of a visual display.
The other evidence that dinosaurs were able to communicate stems from the CT-scan analysis of various dinosaur skulls. Certain dinosaurs (like the duckbilled hadrosaurs) sported large head crests with chambers and what purpose these served was not understood. Recent studies completed with have suggested, however, that these chambers may have worked as a resonator for loud sound which would made communication quite easy when the hadrosaurs travelled in packs or groups. It is believed that warning bellows would have been emitted by the hadrosaurs when they saw a predator.
The more we find out about the behaviors and habits of these extinct creatures, the more interesting we find them!