Human beings rely on the natural environment and resources provided by the earth for survival, reproduction, and the development of civilization. However, with the rapid urbanization of human society today, although the natural environment still provides human beings with endless "ecosystem services," people often forget the connection between themselves and nature. This course will explore the complex and diverse relationships between humans and the nature, rediscover the lost links, and further investigate human overuse of natural resources and the destruction of the environment, which has led to a serious threats in biodiversity. This in turn poses a severe threat to the well-being of modern humans and the sustainability of the future. Finally, we will reflect on how to apply modern science and technology to solve such problems. This course will use various methods such as lectures, news reading and analysis, speeches, field trips, student group actions and reports, classic film viewing, etc., to discuss environmental ecological issues in Taiwan and internationally. It will stimulate students' concern for the natural environment and their willingness to take action, and cultivate their critical thinking skills.