If I were to pluck an animal out of the ocean to use as a Christmas tree ornament, it would most definitely be the sea gooseberry (Pleurobrachia bachei). Spherical and glittery, like a glass bauble, it would bring lots of holiday cheer to my living room.
Now, don’t get any crazy ideas. I’m not actually suggesting that this would ever work out – out of water, it would lose its shape (never mind its life) and its ability to shimmer. Instead, it would droop and hang off a tree bough like a goop of … well you get the idea.
However, what I am saying is… ain’t it purdy?
Unlike other animals that create light inside their bodies through a chemical reaction (bioluminescence), this jelly refracts light with its tiny rows of beating comb plates – thus giving it that rainbow sparkle. And its glass-bauble look is actually useful. Many jellies (gelatinous zooplankton), including comb jellies, are transparent to light. It’s a way for them to “hide” in plain sight in sunlit open water areas that don’t offer any shelter.
Some comb jellies (also known as ctenophores – the group of animals which the sea gooseberry is a part of) do bioluminesce as well, just not the sea gooseberry.
Learn more about bioluminescence and the lives of other deep-sea animals during Luminescence: a celebration of aquatic light through January 22, 2014.
Watch the video below and enjoy the sea gooseberry’s light show.
Written by Karen Horak, writer-editor, content and digital experience at the Vancouver Aquarium.