Our understanding of dinosaur biology is changing all the time, both with new fossil discoveries and new technologies with which to interpret them. Although some argue in favor of conspiracy theories, we are beginning to put together a solid understanding of what these massive animals probably looked like. In time, we'll learn even more, and our collective mental image will adapt once again; nonetheless, the picture is clearer than ever before.
Through clever use of comparative biology, pigment analysis, and powerful new X-rays, paleontologists have a renewed confidence about the physical appearance of dinosaurs. This includes everything from their colors to their eating behaviors to the shapes of their tongues. The results can be as impressive as they are strange.
Since soft, fleshy parts are hardly ever retained in fossil form, dinosaur tongues have generally been something of a mystery; however, paleontologists have found some insights by looking at surviving hyoid bones.
Many animals have a hyoid bone that anchors the tongue, but the shape and complexity determines how "mobile" the tongue is - how much it could actually move around on its own. The hyoid bones in dinosaurs varied by the type. Most dinosaurs - including all carnivores - had simple tongues that mostly laid flat, similar to those of a crocodile.
Despite the vegetarian nature of long-necked dinosaurs like the Brachiosaurus and Abydosaurus mcintoshi, these herbivores apparently did not chew their food. This is demonstrated by their teeth, which are not the right shape for chewing, and their body shape, which suggests they would want to feed as quickly as possible.
After decades of assuming these dinosaurs would have lived and fed in deep, watery swamps, paleontologists later realized this assumption was incorrect. Instead, they would have slowly roamed fertile floodplains. This recent reevaluation also shows the Brachiosaurus would have had its nostrils on the front of its face, not the top.
Archaeopteryx is often considered the first bird, a key moment at which dinosaurs began taking to the skies. How well the Archaeopteryx could fly has long been a subject of debate, but researchers at the European Synchrotron Radiation Facility think they may finally have an answer.
Incredibly detailed X-ray scans have revealed previously unknown aspects of the creature's anatomy, including the thinness of its bones' outer walls. By comparing the data to 55 modern birds, as well as crocodilians and pterosaurs, the ESRF researchers found that it compared best to modern quails and pheasants. Neither bird normally flies, but they do both take to the air for short bursts. The Archaeopteryx seems to have done much the same.
For a time, it was thought feathers were limited to the theropod dinosaurs, a mostly two-legged, carnivorous group. A new fossil discovery in Siberia, however, suggests feathers were found across many different groups.
It appears one of the main functions of dinosaur feathers was insulation, so those who lived in warmer climates likely had fewer feathers than did their cold-weather counterparts. Bigger animals also struggle less with keeping cool, so it's believed that large dinosaurs wouldn't have had much use for these types of feathers. Particularly large dinos living in warm weather may not have had feathers at all.