In a new(-ish) article in The Plant Cell, Patrice Salomé and Sabeeha Merchant review the history and utility of the green alga Chlamydomonas reinhardtii as a model organism. The article discusses the advantages of Chlamy as a model organism, the scientific questions it has been used to explore, the history of Chlamy research, the characteristics of the species, the existing resources and databases, and genetic and genomic techniques. It’s a good introduction to Chlamy research in a more easily-digestible form than the massive, three-volume Chlamydomonas Sourcebook.
Folks, it’s been fun. I feel like I had a pretty good run as a scientist. I met some amazing people, went to beautiful places, and learned things I never would have imagined (Hodgkinia, WTF?!). With all my frustrations and failures, I’ve never once regretted going back to school and becoming a biologist. But now I need to close the door on all of that and find a new way to make a living.
¥50,000 is ¥50,000! Applications for travel fellowships from the Kato Memorial Bioscience Foundation for the Fifth International Volvox Meeting are due tomorrow. These fellowships are to help non-Japanese students and postdocs travel to Tokyo for the meeting. ¥50,000 is around $500, a pretty good return for an easy application. Answer a few questions, send an email, and your trip could be $500 cheaper:
Applicants are required to submit a pdf file of the completed application form (download here) to Volvox2019 Office (E-mail: volvox2019 (at) gmail.com)
The Royal Society of Biology deadline is also coming up soon (March 1).
Imagine you’re swimming in nice, warm water, happily making your own food without a care in the world (other than zooplankton). You just need to store up enough starch before nightfall to hold you through the night so you can quit swimming, absorb your flagella, and wait for the sun’s return. You see a green light below, and you swim toward it. You can’t help yourself; your phototactic machinery is hardwired to respond.
Next thing you know, you’re captured by a giant, tentacled polyp. You look for a way out, but there is none. You’re stuck there for the rest of your life, forced to work and have the food you produce stolen by your coral overlord. Resigned to your fate, you absorb your flagella and get down to photosynthesizing.
Last year I wrote a series of posts on convergent evolution and misrepresentations of the history of the concept by proponents of intelligent design including Günter Bechly, Lee M. Spetner, Granville Sewell, and others. I didn’t intend for there to be a two-month gap before the final installment (nor am I sure this is the final installment), but here we are.
The Discovery Institute is producing a revisionist history. To hear them tell it, convergence is something that evolutionary biologists have either barely heard of or that they “invented” or “made up” to hide problems with the tree of life. Convergence “destroys the tree of life,” it “contradict[s] the [modern synthesis],” and it is “quite unexpected” to evolutionary biologists. All of that is a big, stinking pile of wrong. In reality, biologists since Darwin, and including Darwin, have always appreciated the importance of convergence, have written thousands of papers about it, and have included it in every evolutionary biology textbook I’m aware of.
I explained why the argument that convergence is evidence against common descent is daft, and I gave a spectacular example of convergent (or parallel) recruitment of life cycle genes in plants and brown algae. I also promised that I would write about convergent evolution in Volvox, which I have so far failed to do.
The Trump administration is expected to announce reductions to the waters protected by the Waters of the United States (WOTUS) rule in a couple of hours. The change is expected to remove at least some wetlands, ephemeral streams, and headwaters streams from the waters covered by the rule.
According to MSNBC,
Mark Ryan, a lawyer at Ryan & Kuehler PLLC who spent 24 years as a clean water expert and litigator at the EPA, said water systems called headwaters in high regions of the country could lose protections under the new definitions being proposed by the Trump administration.
“I think the mining is going to benefit from this because mines tend to be up in the mountains near headwater systems,” Ryan said.
Miners may no longer need to apply for a permit before pushing waste from operations, such as rubble from mountain-top coal mining in the eastern United States, into some streams.
You are more closely related to a mushroom than a kelp is to a plant. It’s strange to think about, but it’s true. Kelps seem very plant-like, with their root-like holdfasts, stalk-like stipes, and leaf-like blades. But kelps are brown algae, part of the stramenopile (or heterokont) lineage of eukaryotes, which are very distant from the land plants and their green algal relatives, all of which are within the archaeplastida (the direct descendants of the primary origin of chloroplasts). Mushrooms (fungi) and humans (animals), on the other hand, are both opisthokonts, practically cousins at the scale we’re talking about.
David Kirk called the Chlorophyte green algae “master colony-formers” because multicellularity has evolved so many times within this class:
Although members of most chlorophycean genera and species are unicellular flagellates, multicellular forms are present in 9 of the 11 chlorophycean orders (Melkonian 1990). Multicellularity is believed to have arisen independently in each of these orders, and in some orders more than once.
In contrast, multicellularity has probably only evolved once or twice in the probable sister group of the Chlorophyceae, the Ulvophyceae. So when numbers like 25 get thrown around for the number of times multicellularity has evolved, something like half of those times were in the green algae.
We know a lot less about how multicellularity evolved in the Ulvophyceae than we do in the volvocine algae within the Chlorophyceae. A big step forward in understanding ulvophyte multicellularity happened last week, though, with the publication of the Ulva mutabilis genome.
I got my copy of Jillian Freese’s A is for Algae earlier this week. Freese, a Ph.D. candidate at the University of Rhode Island, says the book is “Part birthday gift. Part #scicomm. Part stress relief.” It’s full of watercolor paintings of algae, mostly seaweeds but with some phytoplankton as well. Each species (one for each letter of the alphabet) is presented with its scientific name, usually a common name, habitat and biogeographic information, and some interesting factoids.
Warning: spoilers below the fold.