The amount of crop damage caused by Japanese macaques on Yakushima Island has significantly decreased, thanks to the use of electric fences and other preventive measures. However, local people continue to request the capture of Japanese macaques that cause damage, raising concerns about the conservation of Japanese macaques. This study aims to understand the underlying structure of these problems and propose solutions by focusing on local people's perceptions of damage, rather than on quantitative criteria such as the amount or quantity of damage. We interviewed village leaders and farmers, inspected electric fences, and analyzed relevant documents. Based on these findings, we examined the local people’s perception of the damage and the factors that lead to it on a village- by-village basis. The results suggest that one of the current problems on Yakushima Island is occurring mainly in areas where home-grown fruit trees are cultivated, where crop damage occurs due to inadequate installation and management of electric fences. In these areas, negative perceptions of damage are often exaggerated, such that damage is regarded as large even if the actual amount of damage is small. Another problem is the gap between current pest control practices on Yakushima Island and ideal practices for managing Japanese macaque populations. This gap may stem from the unclear hunting policy presented by the local government, hunters' customs, and the hunting permit system. These two problems may be led to excessive hunting of Japanese macaques. To address these issues, we propose the establishment of a system to facilitate the management of electric fences, the creation of opportunities to mitigate the negative perception of damage, and the development of a more systematic approach to hunting Japanese macaque.

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In this paper, I discuss the relationship between social organization and offspring-rearing methods, which are starting to be used as a novel indicator in interspecies societal comparisons. Additionally, I clarify the relationship between the intimacy of the mother–offspring relationship and the development of foraging in the offspring. I suggest that the establishment of a base camp in human evolution is important not only to facilitate effective hunting and gathering but also for immature individuals to reduce the cost of accompanying adults and engage in their own foraging activities.

I also attempt to deconstruct weaning from the offspring’s perspective, which often focuses on the mother’s decision to stop breastfeeding. Specifically, I focus on the development of the offspring’s ability to acquire food independently and the offspring’s behavior away from its mother. I suggest that there is no significant difference between humans and African apes in the timing when the offspring significantly reduces its dependence on breast milk. This paper also depicts “early weaning” as a characteristic of the unique life history of humans, in which the mother conceives a second offspring at the same time as or even before the offspring becomes much less dependent on the mother’s milk.

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