Tpo 44

The lecture and the reading disagree on the merit of the fact that most animals species in the past were almost huge and massive in their sizes. The article states that many scientists suggest several explanations. He suggests that the abundance of the oxygen gas, also the plenty of nutrients, and the warmer atmosphere are behinds that successful massive sizes. In contrary, the listening passage casts doubt this idea. He rebuffs the three explanation of the writer and proves that they are unconvincing as the following.

First of all, the author asserts that the level of the Oxygen gas was very high in the past. He supports that the Oxygen gas plays an essential role in the good and healthy life of all animals. Therefore, it is a good reason to support why those mammals and animals were very large. However, the professor challenges this point and says that the Earth was rich with active volcanoes at that time. He claims that those volcanoes produced a high contaminated environment. Furthermore, this atmosphere was rich with poisonous and toxic gases which in fact endangered those animals. Therefore, the oxygen was not clear enough to help those extinct animals to live and grow to that magnificently massive size.

Second, the reading paragraph believes that the assortment of plants in the past provided variety of food and nutrients. He explains that those plants enabled the life to create that massive sizes of animal species. On the other hand, the lecture refutes this explanation also. He thinks that those plants were not the source of nutrients for those animals. For many, the fossils of scares plants show that they hold trivia level of nutrients. Besides, they increased the level of the carbon dioxide gas in the environment which created more contamination in the surroundings.

Least but not the last, the reading passage conducts that weather was warmer enough to encourage the animals to grow and have that larger size, he explains that this hot climate stimulated the growth of them; because those animals did not need to waste more energy to stay warm in an area rich in nutrients. So, they tended to be enormous size. Whereas the speaker rebuts this reason also. He opposes this view by claiming that the smallest animals usually live in the warmer climate, and the largest live in the coldest ones. Therefore, those huge animals in the cold area need higher energy to stay warm and maintain their body temperature.