Both the reading and the lecture discuss whether dinosaurs are endotherms or not.

Both the reading and the lecture discuss whether dinosaurs are endotherms or not. The author thinks that dinosaurs are endotherms, the speaker, however, disagree with the author`s the point of view. The first reason the author says that, in polar regions some dinosaur fossils have been found, which shows that just endotherms keep their body temperatures constantly, so the dinosaurs are endotherms. The speaker, on the other hand, says that the discovery of the dinosaurs fossils does not indicate that they are endotherms. She goes on to say that, the dinosaurs may migrate or hybernate when the climate is cold, so they can not be considered as endotherms. The author says that the leg position and the movements of dinosaurs, which are under the body, show that they are endotherms. But, according to the speaker, having legs under their body does not mean that they would use their legs for running, actually legs help dinosaurs to grow up larger and larger. The author concludes that the canals in the bones of dinosaurs, which the haversian canal is one of the structure that endothermy have, shows that dinosaurs are not reptiles but endotherms. The speaker, though, has a different point of view. She says that, although dinosaurs have this special types of cannals, they also have `growth rings` which are the indicators of reptiles. These growth rings tells us that dinosaurs grow too slowly in colder periods, and at normal pace in normal seasons. In contrast to this, endotherms` growth is more rapid.