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

According to the evidence of the argument: the colossal mammals in the Kaliko Islands extinct after 3,000 years of human arrival, the bones of fish, and the uncovered simple tools, the author concludes that the human behavior of excessive hunting led the giant mammals to extinction. There are a few issues render the argument unconvincing.

First of all, the author indicates that most mammal species were not alive anymore within 3,000 years after the advent of the human beings. The problem with this assumption is that 3,000 years is quite a long time. There might be many other reasons cause the extinction. For instance, 3,000 years is long enough for climate change. Many areas suffered for climate change and then the animals there would face the fate of doom. Therefore, there is no obvious causation between the extinction and the human behavior.

Secondly, the writer contends that the place of fish remains was discovered so that the humans probably also hunted mammals. Nevertheless, the skills as well as tools of hunting the fish are completely different from hunting the mammals. The human beings might have the knowledge and expertise to capture the fish, but not the mammals in large size. This assumption fails to distinguish the difference between the fish and the colossal mammals.

Thirdly, the author states that the simple equipment has been discovered by researchers. The hypothesis render a doubt that how could simple equipment like stone knives capture and kill a huge mammal. Meanwhile, the humans could be attacked by enormous mammals, too. If the weapon was not advanced enough to fight with huge mammals, the humans could be the prey. Besides, it is possible that the basic equipment might be used for basic living behaviors, such as cutting down tree branches, cooking food, and making clothes, but not hunting huge mammals.

Finally, the conclusion supported by the writer that the humans hunted the giant mammals to death is plausible for previous reasons. To bolster the argument, the author needs to provide more information about the history and environment change of the 3,000 years after the appearance of the human beings in the Kaliko Islands, the causation between fish bones and mammals, and the possibility of simple tool to conquer the huge mammals.