▶ Your Answer :
The reading passage covers three major
points concerning the explanations of extinction of Diprotodon. The speaker,
however, clearly states why these points are debatable.
The first point made by the author is that
Diprotodon had very low birth-giving rate. However, the listening challenges
this by mentioning that Koala bears, which are close relative of Diprotodon,
could survive even though Koalas have much lower reproduction rate than
Diprotodon had. Hence, the low reproduction rate may not be an effective reason
to explain the extinction.
Another point made by the writer is that
sudden and severe shortage of meal, saltbush, which is wiped out by humans, led
the Diprotodon's extinction. On the contrary, the lecturer asserts that this is
not true due to the fact that, after people had cleared the land using fire,
nutrient content increased in saltbush. Moreover, Diprotodons were not only
able to eat saltbush but also able to consume other types of plants. Thus, the
scarcity of food might not be a persuasive reason to support the vanishing of
Diprotodon.
Lastly, the reading claims that Diprotodons
decimated by predators because such large preys were easy meals. The professor debunks
this by saying that only few species could hunt the colossal animals. In
addition, Diprotodons and their predators had coexisted for more than 100,000
years. Therefore, the fact that the predators annihilated Diprotodons is
probably not a viable explanation. |