▶ Your Answer :
In this set of materials, the reading passage states that Tyrannosaurus rex cannot run, whereas the listening casts doubt on it.
To begin with, the author claims that T.rex would not be able to run around in the jungle environment since jungle is dense with vegetation. Running within the jungle would be very dangerous for T.rex. The professor, however, argues this point by insisting that T.rex do not just run around in the jungle since they are smart enough. They stock their preys without being noticed and catch their preys by surprise. This is not dangerous at all for T.rex.
Moreover, the text declares that T.rex's long and thin legs prevented T.rex to move quickly. Usually animals with long and thin legs and heavy bodies move slowly because running will cause tremendous stress to their legs. Likewise, with this reason, T.rex is most likely to move slowly. The speaker challenges this point saying that each foot T.rex touches the ground is very brief which will not be very stressful to T.rex's legs. He also lists some other animals that have long and thin legs but can move fast, such as horse, giraff, and chicken.
Lastly, the writer demonstrates that T.rex's body mass distribution was not capable of running. In order for an animal to run, it needs about 85 percent of body mass to be leg muscle. However, T.rex's leg muscle was small fraction of their body mass which would be difficult for them to run. The lecturer refutes, saying that we do not know exact body mass distribution of T.rex. Since we only have the skeleton of T.rex, we do not have complete picture of T.rex which it may be not true that T.rex has little leg muscles.
|