Why do you think watching the kingfisher made Brian think about making a spear?

Watching the kingfisher likely inspired Brian to think about making a spear because he observed the bird's precision and efficiency in hunting. The kingfisher's ability to dive and catch fish effortlessly demonstrated a successful method of survival, prompting Brian to consider creating his own tool for fishing. Additionally, the bird's grace and skill may have sparked Brian's creativity and resourcefulness, motivating him to adapt to his environment using available materials.