Each concept here is mapped to its prerequisites — the ideas you'd need first to understand it — all the way down to four foundations: Space, Time, Energy, Pattern. Click any prerequisite to drill down, or scroll for the chain graph.
Otters are living organisms that inhabit water-rich environments, characterized by their ability to interact with and respond to their aquatic surroundings.
External reference — all senses of the word “otter” on Wiktionary. This atlas concept maps to only the slice of meaning relevant to the prerequisite graph.