Creatures, Strange and Complex, in Colorful Detail CreatureCast A change encounter with the colors of a squid. The famous Nobel-winning scientist, Marie Curie, once said: "A scientist in his laboratory is not only a technician: he is also a child placed before natural phenomena which impress him like a fairy tale." Casey Dunn is just trying to bring a little bit of that fairy tale back to science. A Brown University scientist, Dr. Dunn has added animation director to his list of titles over the last four years. In 2009, with money from the National Science Foundation for an audio podcast project, Dr. Dunn was convinced by a student - and a squid - to create animations instead. That student, Sophia Tintori, was working on a project on the squid's very changeable colors. Once Dr. Dunn saw what she created, he said there was no turning back. "A lot of scientists come to science in first place because they find science beautiful; they find themselves mesmerized by looking at the stars or watching organisms or the imagery of the deep sea," he said. As you watch the colorful crepe paper drama unfold in CreatureCast, you just might be mesmerized, too. A small army of student animators, most without previous experience, have taken viewers everywhere from to the bottom of the ocean, to see how the solitary angler fish finds and keeps a mate, to the tree tops, to find the strangler fig making trees hollow from the outside in. Dr. Dunn believes that the benefit of these small, endearingly imperfect films - created from pencil, paper, crayon and even cut up issues of National Geographic - extends well beyond his classroom. By training the aesthetic appreciation into students in the early days of their scientific careers he is preserving that sense of mesmerized beauty they came to science for. He is also helping them learn how to share it with the rest of us. CreatureCast will appear periodically at nytimes.com/creaturecast. Here, Casey Dunn introduces the newest episode: "Sex in Spoonworms." By Alysse Austin What if you had a tiny husband, about the size of a breath mint, that lived in a chamber within your body and produced sperm on an as-needed basis? This is how mating works in the green spoonworm. What if a man was the size of a breath mint? And what if a woman had a chamber in her body where he lived out his entire adult life, absorbing nutrients and contributing sperm when she was ready to have babies? Though this arrangement is quite different from how humans live together and reproduce, for the green spoonworm, Bonellia viridis, it's just everyday existence. All green spoonworms are born sexless. They have no chromosomal differences that fate them to be male or female, as we do. Instead, green spoonworm larvae search the ocean floor for females. If they find one, they become male and take up residence inside her body. If they don't, they settle to the bottom and grow into the female they never encountered. In many species, males and females are nearly indistinguishable. Just try to figure out the sex of your pet parrot. In some species, there are conspicuous differences in size, shape, and behavior between the sexes. You can tell a rooster and a hen apart, though each is recognizable as a chicken. In other species, males and females are so different that they were initially described as completely separate species. This was the case for the males, females, and juveniles of whalefishes, until DNA and anatomy revealed the misunderstanding decades later. The green spoonworm is at one extreme on this spectrum of sexual differences, and we are closer to the other end. Alysse Austin, a senior undergraduate student at Brown University, explains the lifecycle of the green spoonworm in this episode of CreatureCast. The song is Sneeuwland by Oskar Schuster. Ms. Austin made this animation in my Invertebrate Zoology course last fall. Casey Dunn More animations and images can be found at creaturecast.org, a project supported in part by the National Science Foundation.