▶ Your Answer : The lecturer explains about the holes in the theories regarding the extinction of Diprotodon, the marsupial lived Austrailia long time ago. Specifically, he targets three well known theories that assumes the Diprotodon's extinction was based on 'low reproductive rate', 'shortage of food', and 'predators'. According to the lucture, frist and the most problematic of all, the theory of 'low reproductive rate' is not true. The theory presumes that the low number of offspring which is around eight made Diprotodon to be extint. However, the lecutre points out that similar speices like 'Koala' has survived in Australia with only five offspring rate. Thus, the number of offspring can not be the matter on adopting the environment. Secondly, with regard to the theory of 'shortage of food', the lecture disagrees that burned land by humans made food shortage. In fact, the fire made the soil to be fertile with more nutritions. Further more, Diprotodon might have alternative food source except slatbush. Lastly, the theory that predators ate all the Diprotodon also has weak points. Considering the size of Diprotodon which wieghed over 2,800 kilograms and four meters tall, there were not many predators can hunt this large herbivore. In conclusion, according to the lecutre, three theories on the reading passage have holes in their ground as noted above. |