baptista
Mar 16, 2017
Writing Feedback / Discussion about if dinosaurs are endotherms [5]
@Holt
Thanks for your comment！I will try to make it better.
@Holt
Thanks for your comment！I will try to make it better.
baptista
Mar 15, 2017
Writing Feedback / Discussion about if dinosaurs are endotherms [5]
Thanks for reminding me. Here is the reading passage: (copy-pasted / removed)
Thanks for reminding me. Here is the reading passage: (copy-pasted / removed)
baptista
Mar 9, 2017
Writing Feedback / Discussion about if dinosaurs are endotherms [5]
The lecture talks about the problems with theories presented in the passage which tries to explain that dinosaurs are endotherms. It gives several facts and details, with which the theories are inconsistent.
First, the lecture does not believe that only endotherms can live in the polar regions because of their ability to maintain their own body temperature, thus dinosaurs fossil found in Polar Regions indicates they belong to endotherms. That is because the climate of the period when dinosaurs lived in Polar Regions is warmer than nowadays so that the dinosaurs would not be bothered with cold climates. What's more, even during the cold period, the dinosaurs could migrate to other regions or hibernate like other reptiles do. Therefore, living in Polar Regions could not prove that dinosaurs are endotherms.
Second, even though the reading passage suggests that endotherms have their legs under their body in order to sustain agile physical activity, so the fact that the dinosaurs' legs are positioned underneath their body suggests they are endotherms, the professor argues in the lecture that the reason why the dinosaurs' legs under their body is to add their own weight, rather than supporting activities like running. That is because the bigger a dinosaur can grow, the stronger power it would appear, which means the dinosaurs had no needs to run. Obviously, the professor's argument contradicts its counterpart in the reading.
Third, although many dinosaur bones do have Haversian canal like most of the endotherms , it doesn't prove that the dinosaurs were not always rapidly growing, whereas that fact that the growth rings which the dinosaurs have confirms the frequent fluctuating growing pace of the dinosaurs which is consistent with the characteristic of non-endotherm animals. It is claimed that dinosaurs stopped growing or grew slowly when the climates were cooler, while true endotherms keep growing rapidly a whole year-round.
Are dinosaurs endotherms or not?
The lecture talks about the problems with theories presented in the passage which tries to explain that dinosaurs are endotherms. It gives several facts and details, with which the theories are inconsistent.
First, the lecture does not believe that only endotherms can live in the polar regions because of their ability to maintain their own body temperature, thus dinosaurs fossil found in Polar Regions indicates they belong to endotherms. That is because the climate of the period when dinosaurs lived in Polar Regions is warmer than nowadays so that the dinosaurs would not be bothered with cold climates. What's more, even during the cold period, the dinosaurs could migrate to other regions or hibernate like other reptiles do. Therefore, living in Polar Regions could not prove that dinosaurs are endotherms.
Second, even though the reading passage suggests that endotherms have their legs under their body in order to sustain agile physical activity, so the fact that the dinosaurs' legs are positioned underneath their body suggests they are endotherms, the professor argues in the lecture that the reason why the dinosaurs' legs under their body is to add their own weight, rather than supporting activities like running. That is because the bigger a dinosaur can grow, the stronger power it would appear, which means the dinosaurs had no needs to run. Obviously, the professor's argument contradicts its counterpart in the reading.
Third, although many dinosaur bones do have Haversian canal like most of the endotherms , it doesn't prove that the dinosaurs were not always rapidly growing, whereas that fact that the growth rings which the dinosaurs have confirms the frequent fluctuating growing pace of the dinosaurs which is consistent with the characteristic of non-endotherm animals. It is claimed that dinosaurs stopped growing or grew slowly when the climates were cooler, while true endotherms keep growing rapidly a whole year-round.
