Archaeopteryx suggested that "Archaeopteryx" was a dinosaur that was no more closely related to birds than were other dinosaur groups. Kurzanov (1987) suggested that "Avimimus" was more likely to be the ancestor of all birds than "Archaeopteryx". Barsbold (1983) and Zweers and Van den Berge (1997) noted that many maniraptoran lineages are extremely birdlike, and they suggested that different groups of birds may have descended from different dinosaur ancestors. The discovery of the closely related "Xiaotingia" in 2011 led to new phylogenetic analyses that suggested that "Archaeopteryx" is a deinonychosaur rather than an avialan, and therefore, not a "bird" under most
Dinosaur tooth data that has been collected through dinosaur dental histological studies are typically unavailable through other means and has provided us with a more in-depth understanding on their biology. One of the most significant findings is that despite differences in their appearance, dinosaur teeth are essentially composed of the same dental tissues found in modern mammals, crocodilians and other amniotes, suggesting that these tissues first evolved in a common ancestor and has been retained ever since. Another finding is that the lines of von Ebner can be counted similar to tree rings to determine the age of a tooth. Furthermore, as