Humans arrived in the Kaliko Islands about 7,000 years ago, and within 3,000 years most of the large mammal species that had lived in the forests of the Kaliko Islands were extinct. Previous archaeological findings have suggested that early humans general

The argument indicates that human beings bring the doom to the mammals in Kaliko by providing some pieces of evidence: the extinction of large mammals after the advent of human beings and people hunt the mammal to death. However, there are many other alternatives which might also cause the same result, the extinction of the mammals.

The first alternative explanation could be global climate change. The argument mentions that the giant mammals extinct after 3,000 years of humans’ arrival. 3,000 years is a so long term that the climate before might be different with the climate 3,000 years later. It is possible that within the 3,000 years, the global climate changed naturally, and the weather of Kaliko Islands does not suitable for the giant mammals anymore. Then, the giant mammals died naturally without the hazard of humans.

The second possible explanation could be the resource competition. Probably, the humans and the extinct mammals hunt for the same prey. If they compete for the same food resource, one side might lose their food resource and then gradually die. Therefore, the mammals might unfortunately be the loser in the competition of the food resource, fish. In this way, the death of huge mammals is because they lack food, but not they are prey.

The final alternate explanation could be changing of the ecosystem of Kaliko Islands. Perhaps, the people arrived in Kaliko use knives and they can cut down trees to construct their shelters. The colossal mammals might live in the forest and then lose their habitat since the trees are gone and the forests are damaged. The enormous mammals might fail to adapt to a new lifestyle without trees and forests, and as a result, they disappeared in Kaliko.

In the conclusion, the humans hunt the giant mammals so excessively that they extinct at the end might not be the sole answer. There are many different ways which could also cause the extinction, such as climate change, food resource competition, and ecosystem change.