CreatureCast – Cilia

posted by Casey Dunn / on January 27th, 2014 / in Comb Jellies

Many organisms move with cilia. Most, like Stentor, are small. The ctenophores (also known as comb jellies) are an exception – they are the largest animals to use cilia for swimming. Ctenophore cilia refract light into beautiful pulses of color as they move. Sid Tamm recently published an excellent review of of ctenophore cilia (unfortunately the full text is only available to those with a journal subscription).

Filmed and edited by Stefan Siebert. Original music written and performed by Bryn Bliska. We originally posted this episode at the New York Times.

Six tips for achieving invisibility

posted by Sophia Tintori / on April 15th, 2013 / in Arthropods, Cnidaria, Comb Jellies, molluscs, optics

 Hiding from danger in the deep sea is a very different game than hiding from danger on land. In the sea, not only does a creature have nothing to hide behind, it can’t even camouflage itself, because it’s environment is just clear water. Perhaps not surprisingly, then, many animals of the sea have evolved ways of being transparent.

Here is a semi-interactive video (with the option of a single, non-interactive video here) from CreatureCast alum Sophia Tintori, featuring tips from a handful of ocean-dwellers that each have drastically different approaches to being invisible.

Score by Amil Byleckie, video made by Sophia Tintori, with a big thanks to Sönke Johnsen. Funding provided by Duke University Provost & Council for the Arts and the Office of Graduate Education at the University of North Carolina Chapel Hill. Released under a Creative Commons Attribution-Non Commercial-Share Alike license.

Gelatinous animals

posted by Casey Dunn / on May 31st, 2011 / in Comb Jellies, Jellies, Siphonophores

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

posted by Sophia Tintori / on September 27th, 2010 / in Arthropods, Comb Jellies, Dinoflagellates

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 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

posted by Sophia Tintori / on December 21st, 2009 / in Comb Jellies, Podcast (Student Contribution)

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

posted by Sophia Tintori / on December 6th, 2009 / in Comb Jellies, locomotion, Podcast (Student Contribution)

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).