TPO 4

The passage indicates some reasons that dinosaurs were endotherms. In contrast, the professor refutes the article and provide some reasons against evidence in the passage.

First, according to the passage fossils that were found in polar regions are a considerable evidence for being endotherms.However, the professor states that polar regions were much warmer at that days. In addition, dinosaurs could migrate to warmer areas when it was cold in polar region as many reptiles do the same.

Second, while the reading illustrates the leg position and movement of dinosaurs as a good point for being endotherm, the professor rejects this point. She says that this position of legs is because of the large size of dinosaurs. This position of legs could support more weight.

Finally, professor rejects the third evidence which is mentioned by the passage about Haversian canals in endotherms bone structure. She indicates that dinosaurs bone structure has growth rings. These rings show that these creatures have slow or even stopping growing step during cold times while endotherms grow rapidly with no relationship with temperature.