Showing posts from January, 2012

Weekend links: beautiful and strange

Evolution of Higher Mutation Rates

Post previously published at Beacon Researchers at Work. When I started as an undergraduate in BEACON a year ago, I kept hearing about Avida and how powerful it is to study evolution in action. I decided to teach myself how to use the Avida software, and I quickly discovered that there are no tutorials for biologists interested in the more complex aspects of Avida. Fortunately for me, I was in the heart of BEACON, surrounded by people who were willing to take time to teach me how to use the software. Every single one of the people in the photo below, most of whom are in Dr. Ofria’s Digital Evolution lab, helped me in some aspect of my research with Avida. Now, I am working on creating a tutorial targeted at researchers with no computational background.
Front row (L to R): Charles Ofria, Owen Pierce, and Tasneem Pierce BEACON’s collaborative atmosphere allowed me to start an Avida project of my own. I started my Avida project when I was doing research in Dr. Lenski’s Experimental Evol…

Sea urchin tube feet

Ever wonder how sea urchins move? They have neat “tube feet” around their entire body, which extend using a water vascular system and have ends that attach to surfaces. The S. purpuratus urchins I work with are really good at attaching to surfaces, so whenever I move them, they leave lots of tube foot endings. So, of course, I took some pictures of the remnant feet under a microscope (each image is at a different depth, since these are 3-D entities). These feet were bright orange and blue/gray colored, but the camera is monochrome, so I’ll leave the color up to your imagination. -Yasmeen

Pursuing Plants in Peru

[Click through for glorious high-resolution versions of the Andes landscapes and flower close-ups. -- Ed.] The Neotropics is the most species-rich center of plant diversity on Earth, and the plants of the Andes are one of the major elements of the Neotropical flora. The Andes are home to many endemic species, belonging to lineages which radiated into the montane environments that appeared during the uplift of the world’s longest continuous mountain range. In the foothills of the Peruvian Andes, the plant groups which we study are particularly diverse. We, in this case, are two of the current graduate students in Dick Olmstead’s lab at the University of Washington. Our research group is focused on the study of molecular plant systematics – using molecular tools (primarily DNA sequences) to infer the evolutionary histories of particular groups of plants. Pat Lu-Irving works on the Lantana tribe, in the verbena family; John Chau studies the genus Buddleja, part of the figwort family…

Plant epidermal development

Hello, fellow Bio Grads, my name is Henry Hunter and I'm a current first year. Currently, I'm rotating in the Torii lab and working on stomatal development. Recently, I learned how to use a confocal microscope and thought I'd share my first results. The imaging shows fluorescence of GFP-scrm-D, a mutant version of a protein that plays a role in stomatal differentiation. Hopefully I can get even more results like this!

Adventures in limb regeneration

As you may have heard previously, three out of four limbs were eaten off my axolotl by his sibling before I got him. (Yes, he's a male. Axolotl testes become apparent, one might even say obtrusive, with maturity.) Some owners might see fit to crow to our mailing list about how great it is to own a cannibal. I prefer to observe and then show off the chief amazing feature of the mighty axolotl: limb regeneration. Here is Hex's right front foot from the time it started to be more than a stub. The first two photos are awful — I then installed a light on the tank for a dramatic improvement in imaging performance! — but the weird little elf-boot curl the stub took on at first is discernible. Tetrapod limb development is supposed to require apoptosis to separate the fingers, so I was very interested in seeing whether Hex grew a paddle and then dissolved parts away to make digits. At the macro level, though, it looked a whole lot like little toes popping out of a foot and gett…