Our friend Steve Haddock at the Monterey Bay Aquarium Research Institute has posted a video called “There’s no such thing as a jellyfish.” It surveys a broad diversity of animals that are clear and squishy, and explains why there is no one group called “jellyfish”. Many different groups of animals, from stinging cnidarians to swimming snails, have independently become free swimming, gelatinous, and transparent.
Know Your New England Bioluminescants
Towards the end of the summer the waters around southern Rhode Island get quite sparkly at night. I’ve wondered for a while what exactly the sparkling things might be, but it wasn’t until recently that I remembered to bring a bucket with me and look at its contents in the light of day.
When I went out to the ocean a couple of weeks ago, I noticed three distinct sizes of glowing creatures; the tiny specks that make a cloud when you kick the water, the medium ones that look like a pair of triangles, and the big circular ones, that stay glowing for a second or two.
Steve Haddock, one of our friends at the bioluminesence lab at the Monterey Bay Aquarium Research Insitute, helped characterize some of these organisms. Here’s what I found.
The larger circular ones are comb jellies.
We get a lot of comb jellies called Mnemiopsis around here. By the end of the summer there are sometimes so many that it feels like swimming in a giant bubble tea. This seems to be a very young Mnemiopsis, not quite mature yet. Comb jellies don’t have any stinging cells, and are not technically jellyfish– corals and anemones are more closely related to jellyfish than these creatures are, even though these look similar. For more about the psychedelic rainbow colors pulsing down the side of this animal, check out Brown undergrad Lee Stevens’ podcast on comb jellies.
According to Dr. Steve Haddock, bioluminesence correspondent, the smallest size of glowing thing is most probably a bunch of single celled organisms called dinoflagellates.
The last glowing group I found seems to be these copepods, a type of small crustacean.
The appendages at the very back of their bodies are long and thin, but move back and forth so fast that they look like little paddles. These thin appendages whipping around are probably what looked little triangles underwater.
These videos and photos were taken by Sophia Tintori, and released under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 license. Thanks to Steve Haddock for his help. If you see jellies in the water, you should let Steve know at Jellywatch.org. Thanks to Mickey Zacchilli for helping with the video. If you enjoy watching the pulsating comb rows of a comb jelly, here is another clip for you.
CreatureCast – Comb Jellies
This is the third of four contributions from undergraduates in Casey Dunn’s Bio0041 Invertebrate Zoology class. In this episode, Daniella Prince describes the many wonders of comb jellies.
Video by Daniella Prince, with music by Ben Esposito. This podcast is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License.
CreatureCast – Comb Jelly Movement
This installment of CreatureCast is the first of several contributions that were done as final projects by undergraduate students in Casey Dunn‘s Bio0410 Invertebrate Zoology class at Brown University. In episode 3 sophomore Lee Stevens discusses how comb jellies move the same way that many single-celled organisms do, which is remarkable given how much bigger comb jellies are.
This podcast is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License. Narrated and animated by Lee Stevens, with music by Tracky Birthday (this song, and also this one).