The reading and the lecture are both contradicting with each other, in terms of the existence of dinosaurs as an endotherm. The author of the article states that since the dinosaurs were reptiles, they could not be an endotherm. However, the lecturer casts doubt about the claim mentioned in the article and refutes all the theories presented in the article.
First of all, according to the passage fossils of dinosaurs in the polar region is the evidence which leads to the conclusion that dinosaurs were endotherm since they must be required to maintain their body temperature in extremely cold climate similarily as other endotherm animals do. On the contrary, the speaker negates the argument presented in the passage. Furthermore, he discusses that there was a possibility that dinosaurs could be migrated to the warmer region in cold climate or used to follow hibernation, and that way, they do not need to maintain their body temperature.
Secondly, the author posits that the position of dinosaur's legs under the body is the evidence that proves that they are not like other reptiles, so their legs were made for running and therefore, they were endotherm animal. Although the lecturer refutes this by asserting that in order to support their huge weight, their legs were placed underneath their body, and it does not have any relation to the physiological activity, like running.
Finally, it is mentioned in the article that having Haversian canals in dinosaur's bone is the strong indicator which proves that they are endotherm. On the other hand, the speaker again opposes the solution and describes that it is true that dinosaurs had Haversian canal in their bone but they had some growth rings as well which indicates the period of time when their growth was stopped or they were growing slow due to protect themselves in extreme cold. However, endotherm animals always show constant and rapid growth. Thus, rapid growth pattern following the slow growth with again rapid growth was the indicator that dinosaurs were not an endotherm.