Hey, try to make some competition for me? I`m glad to see other`s underwater shots... it is rear. Nudibranches are so fascinating, so various sizes, colors, shapes... Their beauty does not even serve reproduction... they are hermaphroditic! But their beauty (the fantastic colors and patterns) aren`t futile... it is for defense. It warns other predators that they are distasteful or poisonous. Beauty to survive...
very nice and very knowledgeable answer, thank you! :-)
however, my title was meant to point out something else: these colorful creatures live about 30 m or so under the water, where the light is naturally dim and colors all look washed out or grayish... at least for my eyes (i don't actually know what color senses fish have, can you help me here?). they only appear so colorful because i flashed them with light they naturally never get. so... how meaningful is their beauty?
then the second point is that beauty in general is attractive. so it draws attention in a pleasureful way. this might be totally different for fish(predators: maybe for them these colorful nudi branches are scary/ugly/even hurt their senses. again, i don't know enough about it scientifically. but the point is, maybe beauty in this case isn't what we think beauty is... maybe it's the opposite. so again... how meaningful - in our sense - is this beauty?
and last but not least, behind the statement "beauty is futlie" there is a philosophical concept. "futile" can mean "pointless", even though it has a useful intention. but it still is pointless because of it's context, or because of it's missing comparability.