Octopuses are among the most neurologically sophisticated invertebrates, with mounting evidence of sentience that challenges conventional assumptions about marine animal welfare.
Research by scientists including Peter Godfrey-Smith suggests octopuses have rich subjective experiences. They show signs of REM-like sleep with color changes suggesting dreaming, explore novel objects for apparent pleasure, and respond to analgesics in ways consistent with pain experience. Farming octopuses at industrial scale would raise profound welfare concerns given current understanding.