The evolution of complexity

posted by Casey Dunn / on February 27th, 2014 / in Evolution

 

complexity

An increase in average complexity across life through time is not evidence that evolution is biased towards increased complexity. I illustrate this point with a simulation, following up on discussions with Amy Maxmen about her piece on the evolution of complexity in Nautilus.

CreatureCast – Two Urchins

posted by Casey Dunn / on February 27th, 2014 / in Echinoderms

The green urchin and the pencil urchin are alike in many ways, but their differences matter in a big way when it comes to their ecological impacts. We originally posted this episode at the New York Times, where you can read more.

Made by Sofia Castello y Tickell, a research assistant, and Robert Lamb, a graduate student. Both are in Jon Witman’s laboratory.The music is by Jahzzar.

CreatureCast – Kleptocnidae

posted by Casey Dunn / on February 14th, 2014 / in Uncategorized

Glaucus harvests the defenses of its prey and uses them against its own predators. We originally posted this episode at the New York Times, where you can read more.

Produced by Lauren Cheung. The Glaucus illustration is based on the beautiful photo by Taro Taylor. The music is “Thinking of you” by Gillicuddy.

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.

CreatureCast – Tyrian Purple

posted by Casey Dunn / on October 9th, 2013 / in Uncategorized

Nina Ruelle tells the story of Tyrian Purple, a dye created from the marine snail known as Bolinus brandaris. For more information, please see the article at the New York Times where we originally presented the piece.

This episode features the song “humm ok” by Gablé .

CreatureCast – the Central Limit Theorem

posted by Casey Dunn / on October 3rd, 2013 / in Uncategorized

Shuyi Chiou’s animation explains the implications of the Central Limit Theorem. To learn more, please visit the original article where we presented this animation in the New York Times.

The song is Franz Danzi’s Wind Quintet Op 67 No 3 In E-Flat Major, 4 Allegretto, performed by the Soni Ventorum Wind Quintet. The narration is by Pathikrit Bhattacharyya. Further work by Ms. Chiou can be found at her site.

CreatureCast – Sex in Spoonworms

posted by Casey Dunn / on September 21st, 2013 / in Annelids, lifecycles

Alysse Austin, a student in Casey Dunn’s Invertebrate Zoology course at Brown University, describes sexual dimorphism in green spoonworm.

This is the first episode of CreatureCast to be distributed in partnership with the New York Times.

Special thanks to Rachel Kaplan and the Granoff Center for the Creative Arts. Music is “Sneeuwland” by Oskar Schuster.

CreatureCast – PhyloTree

posted by Casey Dunn / on June 4th, 2013 / in Uncategorized

CreatureCast – PhyloTree (full resolution link) from Casey Dunn.

 

An introduction to PhyloTree, a browser for the Tree of Life (or at least a very rough approximation of the Tree of Life) available at dunnlab.org/phylotree .

This video demonstrates some of the features of PhyloTree. It then shows the early explosive discovery of mammal species (most major mammal groups were discovered early on), and then shows the slow and steady discovery of cnidarians (many cnidarians remain to be described). The tool can also be used to quickly find the first species that was described in a group. The first siphonophore to be described, for example, was Physalia physalis (the Portuguese man o’ war).

Music is “Butterfly” by Delicate Steve (delicatesteve.com/).

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.

The Vertebrate Vascular System

posted by Casey Dunn / on October 12th, 2012 / in Vertebrates
Christine Janis, a professor in the Department of Ecology and Evolutionary Biology here at Brown, designed these wonderful animations of vascular systems in vertebrates. Taken together, they provide a clear picture of the evolution of the vascular system, and place our mammalian vascular system in a much broader evolutionary context.
These animations were created in collaboration with Giovanna Roz Gastaldi and Ed Casey of Brown’s Instructional Technology Group, along with student technology assistants.