After having noticed people occasionally ask "do octopuses commit suicide," I found that there is a book on depression that cites a supposed example of an octopus suicide. It's hard to track down the reference, though. The book is The Noonday Demon: An Atlas of Depression by Andrew Solomon, and with a "search inside" for "octopus" on its Amazon pageI was able to find the relevant half-paragraph and footnote: This sounds like a pretty questionable interpretation of the events, even if we assume the facts are accurate, but I figured I'd mention this both to see what comments people have, and so that people looking here for information on this can find a reference. I'd like to find the Marie Asberg reference (It's actually Åsberg for those with the right fonts) but no luck so far. I suspect this is more likely a case of senescence and/or autophagy than one that can be provably attributed to depression in the octopus, but I know the octo keepers can describe behavior that would suggest that octos have "moods" and "personality traits," although I suspect that attributing suicidal behavior is anthropomorphizing them more than is warranted by any evidence I've ever heard. What does everyone else think?