Porpoises maintain mental maps, a mental image of their surroundings, which also includes the topography of the ocean floor. They use that knowledge to find their way around without having to rely on their ability to echo-locate using sound.https://www.youtube.com/watch?v=Mb66zgBUE7kVideo can’t be loaded because JavaScript is disabled: What are mental maps and how do they benefit porpoises? (https://www.youtube.com/watch?v=Mb66zgBUE7k) Share on Twitter Share on Facebook