In the set of the reading and the lecture, the author and the professor both discuss dinosaurs.

In the set of the reading and the lecture, the author and the professor both discuss dinosaurs. On the one hand, the reading argues that dinosaurs, which were the ancestors of modern reptiles, were varied from their contemporary generations and were endotherms by pointing out 3 reasons of supporting: polar dinosaurs, dinosaurs’ leg position and movement, and bones structure. On the other hand, the lecture opposes the author by stating that those evidences in the reading are not correct and dinosaurs were not endotherms. First of all, the reading states that living in polar areas is a firm proof regarding this issue that dinosaurs were endotherms. Just creatures that can keep up a temperature well over that of the encompassing condition could be dynamic in such chilly atmospheres. However, the lecture disagrees by stating that the Polar Regions were significantly hotter than today so that dinosaurs could easily live there in part of the year. Furthermore, another viable reason is that dinosaurs could immigrate or hibernate in cold periods of the years. Therefore, being in pole would not be adequate proof that proves this feature in dinosaurs. In addition, the reading goes on to state that the dinosaurs' leg placed underneath their body instead of at their body side, so they can run easily, unlike crocodiles and lizard. On the contrary, the professor refuses to accept writer’s idea by insisting that if their legs were located at the sides of the animal's body, they would not have been capable of supporting the huge weight of their body. Consequently, they actually needed such tools since they were growing in a large size. So dinosaurs' leg position was under their body, but it was not due to the running purposes nonetheless. Last but not least, the reading indicates that the bone structure of the fossils, which were contained Haversian canals, as the last point for supporting the claims that dinosaurs were endotherms. In contrast, the professor contradicts the writer’s opinion by asserting that the dinosaurs did have the Haversian canals, but there are further indicators that revealed they did not have constant and regular growth. Indeed, in cooled periods they slow down or stop their growing trend, though endotherms animals have rapidly and contentiously growing trend.