22. Building Dens and Fortifications
Octopuses are skilled architects, often constructing elaborate dens from rocks, shells, and debris found on the seafloor.
As detailed in Oceanographic Magazine, these dens provide both protection and comfort, with octopuses carefully arranging materials to fortify entrances and create secure hideaways.
This ability to modify their environment highlights not just intelligence, but also foresight—demonstrating yet another layer of problem-solving in their daily lives.