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 generally relied on both fishing and hunting for food; since archaeologists have discovered numerous sites in the Kaliko Islands where the bones of fish were discarded, it is likely that the humans also hunted the mammals. Furthermore, researchers have uncovered simple tools, such as stone knives, that could be used for hunting. The only clear explanation is that humans caused the extinction of the various mammal species through excessive hunting.

Write a response in which you discuss one or more alternative explanations that could rival the proposed explanation and explain how your explanation(s) can plausibly account for the facts presented in the argument.

In the argument, we are informed that humans arrived in the Kaliko Islands around 7,000 years ago and that these inhabitants witnessed the ensuing extinction of large mammals species in the forests of the Islands within the subsequent 3000 years. Referring to archaeological discoveries, such as fish bones, as well as simple tools like stone knives, the author ascribes the extinction of the various mammal species to excessive human hunting. Reasonable though this explanation might appear, we cannot safely claim that it is the only one that can reasonably account for the facts presented in the argument. Therefore, we must thoroughly consider the following explanations, which rival the proposed one in the argument.

To begin with, the writer attributes the discovery of fish bones to human fishing in the Kaliko Islands. While human fishing might well have resulted in the fish bone remains, the latter could have also sprung from other factors. First of all, it is likely that the unearthed fish bones trace back to a period when human habitation was scarce, or non-existent. If this is the case, then human behaviors had little to do with the fish bone remains and the subsequent mammal extinction. Consequently, the fish bones can be explained as stemming from the fish’s natural death and eventual deposit on the sites later discovered. Second, even if human occupancy in the Kaliko Islands does correspond with the fish habitation, the fish bones cannot be exclusively attributed to human fishing. Instead, it is of equal likelihood that other animals also caught and ate fish and thus contributed to the disappearance of various mammals in the Kaliko Islands. Once the assertion that Kaliko people relied on fishing proves unwarranted, the underlying logic would be weakened, namely: if Kaliko relied on fishing, they must also have had a dependence on hunting the mammals.

In addition, the uncovered simple tools, including stone knives, lend great support to the arguer’s explanation that the annihilation of mammal species arises from human hunting. However, those tools might not have necessarily been used for the stated purpose, but presumably for other reasons as well. For instance, humans living in the Kaliko Islands could have used those tools to document what they had passed through day in and day out or those tools could have been made for aesthetic purposes. Moreover, people could also have used those tools to protect themselves from animal attacks. Without further examination, we cannot decide which explanation finally led to the discovery of such tools. It is even likely that all the aforementioned factors might have conspired to the finding of those tools.

Finally, even if we admit that the uncovered fish bones and those simple tools were used by humans to hunt mammals on the Kaliko Islands, it is reckless to claim that human hunting has reached such an excessive degree that it directly contributed to the extermination of mammals. Other explanations could readily rival the alleged one in the argument. Considerable climate change, which went beyond mammals’ adaptation abilities, the vanishing of food resources on which those mammals relied, or attack by other animals are all possible factors that could have triggered or accelerated the mammal extinction in the the Kaliko Islands.

To draw a conclusion, although human behavior could have exerted negative influence on nature, in the absence of sufficient information, we cannot establish a causal relationship between it and waning of other animal species. The extinction of mammals in the Kaliko Islands is such a case which requires more considerations of alternative explanations that could account for the facts presented in the argument.

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