Here in the Dunn lab, siphonophores are our favorite animal and the focus of much of our research.
Dr. Phil Pugh is a good friend of the lab, and he also happens to have described more new species of siphonophores than anyone who has ever lived. In the video below, he describes what it’s like to come across a siphonophore in the deep sea with a submarine. What looks like one long body in this video is actually a free-swimming colony of clones — many genetically identical bodies that are all attached. But each body in the group isn’t just like its neighbor. They each do a specific job for the colony. Some individuals will swim, some will catch food, and some will reproduce.
More on siphonophore biology can be found in papers here and here. But we’ll talk about all that later — for now, just take a look.
A couple of weeks ago the Dunn lab went out after work, and we got to talking. There’s this thing that usually happens whenever we get together after a day in the lab or field– being a group where everyone focuses in one way or another on the diversity and evolution of reproduction and development, we start to tell stories about how animals reproduce. Someone mentions some surprising tidbit of reproductive biology they recently heard, and that sets it off. Then someone else remembers a weirder story, and tells it. This spurs someone else’s memory, and so on, and then I start feeling overwhelmed.
Well, this time we got caught up on the issue of female choosiness. It takes more energy and resources to make an egg packed with resources, or to raise offspring, or to carry a baby inside the womb, than it does to make sperm. This often leads females to be more selective about their mates than males are. We started talking about ways in which female choosiness manifests itself; sometimes through behavior, sometime through anatomy, and sometimes at the level of the cell. And then sometimes it is all for naught.
In this episode of CreatureCast Rebecca Helm, a graduate student in the Dunn Lab, recounts a few short stories about the many levels of reproductive selection.
This is the fourth of four contributions from undergraduates in Casey Dunn’s Bio0041 Invertebrate Zoology class. This episode is inspired by the fascinating behavior of the flamingo tongue snail, Cyphoma gibbosum, which is described in further detail in Casey Dunn’s earlier post.
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.
This installment of CreatureCast is the second of several contributions that were done as final projects by undergraduate students in Casey Dunn’s Invertebrate Zoology class at Brown University. In episode 4, sophomore Noah Rose delves into the bottom half of the circle of life, where dead things decompose and elements that can then be incorporated into other living organisms are liberated. Noah discusses how the many-legged worms we tend to think of as fish bait impact this process.
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.
In Episode 2 of CreatureCast, Sophia Tintori and Cassandra Extavour talk about the evolution and development of multicellular organisms, and in particular the specialization of reproductive cells. Audio production and animations are by Sophia, who normally studies siphonophores in the Dunn lab. Music by Cryptacize.
We are pleased to present Episode 1 of CreatureCast, by Sophia Tintori. In this first video, Alison Sweeney talks about work that has been done in the Morse lab on Squid iridescence. Audio production and animations are by Sophia, who normally studies siphonophores in the Dunn lab. Music by Lucky Dragons (here, and slowed down versions of this and this) and Sophia on the musical saw.
(Episode 1 was replaced with a new slightly different cut on August 18, 2009. It is now higher resolution and includes a couple different musical tracks.)