How do people in small-scale societies acquire local knowledge of their surrounding environment throughout their lifetimes? How is knowledge acquisition related to their subsistence activities? How are children’s knowledge and skills for subsistence developed? These are key questions for understanding the patterns of local knowledge acquisition in small-scale societies. Although local knowledge of nature among hunter-gatherers and horticulturists has been studied from an ecological approach in geography, ethnoscience, and folk biology, studies on local knowledge from the viewpoints of life course/life history or child growth/development remain scarce.

The purpose of this study was to elucidate life course patterns of knowledge acquisition and identify the factors influencing those patterns by focusing on plant knowledge, particularly tree knowledge, among the Majangir, who engage in swidden agriculture, hunting, and gathering in the forest of southwestern Ethiopia (Gambella Administrative Region). This study utilized a plant-use database of the Majangir obtained from previous fieldwork. Three types of knowledge tests were administered to a group of Majangir between the ages of 9 and 72 years to analyze knowledge variations according to gender and age: 1) a plant name test, where the respondents were asked whether they knew the names of 50 sample species; 2) a tree-use knowledge test, where they were asked about the uses of 24 sample trees; and 3) a tree identification test, where they were asked to identify the sources of 26 small wood samples of about 10 cm in size. Information on their subsistence activities was also collected to investigate relationships between knowledge and those activities.

The results of the plant name and tree-use tests suggested that knowledge was rapidly acquired during the teenage years and slowly increased through adulthood. The tree-use test showed gender differences, probably because of gender-based divisions of labor in subsistence activities. Additionally, the result of the tree identification test suggested a slow increasing trend of scores in the teens through the 30s and a decreasing trend after the 40s. These acquisition and lost knowledge trends were similar to men’s acquisition/loss patterns with regard to honey collecting skills. Honey collection is the most important means of earning cash for men and is particularly challenging to learn as it requires highly advanced skills. These results suggest that patterns of knowledge acquisition differ depending on levels of knowledge and that local knowledge regarding nature is acquired and maintained in strong association with everyday subsistence activities.

Immigrants have become an indispensable part of the Japanese regional economy workforce; in particular, technical intern trainees have recently been receiving more attention in Japanese society. Technical intern trainees sent from China to Japan are governed by China’s labor export policy, Japan’s foreign technical intern training system, the sending/dispatching organizations, the receiving/supervising organizations, and the companies to which they are dispatched.

In the 2010s, the number of Chinese technical intern trainees arriving in Japan decreased due to factors such as stricter regulations imposed by the dispatching agencies in China, the rising wages of Chinese workers, unstable Japan–China relations, and depreciation of the yen. In such circumstances, sending organizations have modified their survival strategies as private companies and their structures are being reorganized.

This paper focuses on sending organizations operating in Qingdao, Shandong province, China, during the slowdown in movements of Chinese technical intern trainees to Japan and analyzes how the sending organizations changed their policies and the types of reorganization occurring in the structure of local sending organizations. The present study also attempted to consider the impact of those policies. The sending organizations in Qingdao have moved away from their traditional policies of dispatching technical intern trainees to Japan to diversify their geographic areas of operation and their work. Strategic shifts related to the posting of technical intern trainees to Japan may be classified into two types: “diversification”; and “maintenance.”

Diversification-type organizations have transformed their policies of specializing in the referral of technical intern trainees to Japan, withdrawn from sending out technical intern trainees, shifted attention to Western countries, and established relationships with other receiving nations. This decision was taken autonomously by such organizations. On the other hand, maintenance-type organizations focus on sustaining their work in technical intern training programs and their primary destination of Japan but are expanding their services to include more specialized and technical workers. This relationship building stance tends to depend more on the receiving side, and unlike diversification-type organizations they make decisions without input from the accepting sides.

Such strategic shifts create diversification and sophistication in the labor export industry in Qingdao.