In animal behavior, when we observe an animal behaving in a certain way, we ask the question,"Why do we see this behavior?" There are four ways to answer the question, "Why do we see this behavior? The four ways of answering the question are (1) how the behavior occurs, (2) what is the benefit of the behavior, (3) how the animal acquired the behavior as an individual, and (4) what triggered the animal to acquire the behavior as a species. These perspectives are collectively referred to as "Tinbergen's four questions. In this practical training, students will gain hands-on experience through observation of marine mammals living in the eastern part of Hokkaido, with the aim of developing the ability to perceive behaviors observed in animals from multiple perspectives and learning methods for quantifying animal behavior.