A new xkcd comic hits the right note: science isn’t about belief. Read the whole thing.
Pharyngula
Evolution, development, and random biological ejaculations from a godless liberal
The latest issue of Science has a fascinating article on Exotic Earths—it contains the results of simulations of planet formation in systems like those that have been observed with giant planets close to their stars. The nifty observation is that such simulations spawn lots of planets that are in a habitable zone and that are very water-rich.
Dynamics of Cats has a better summary than I could give, and it leads in with this lovely illustration of an hypothetical alien organism on one of these hot water worlds.
The only thing cooler than a cephalopod has to be a tentacled alien cephalopodoid. There’s a high-res version of that image at Dynamics of Cats—and I’ve got a new desktop picture.
Since I saw this meme at Dr Crazy’s place, I thought I’d toss it up here for the commenters to make suggestions.
” If I were designing a Pharyngula Halloween costume, it would consist of…”
It’s actually relevant. I just put out a call at my university for volunteers for Cafe Scientifique, which we will be holding on the last Tuesday of each month…and the October calendar puts that on Halloween. I’m going to be trying to organize a panel session on “Mad Scientists and Monsters” as the topic that day, and ask the panelists to show up in costume. So let’s see what suggestions you might come up with!
I’m having second thoughts about the virtues of proximity to my colleagues of that other discipline after watching this video of people plunking alkali metals into water. Cesium looks…interesting.
Fortunately, my chemistry pals aren’t British, or I might have trouble understanding their comments. What the heck does “the dog’s nuts of the periodic table” mean, anyway?
I was reading a review paper that was frustrating because I wanted to know more—it’s on the evolution of complex brains, and briefly summarizes some of the current confusion about what, exactly, is involved in building a brain with complex problem solving ability. It’s not as simple as “size matters”—we have to jigger the formulae a fair bit to take into account brain:body size ratios, for instance, to get humans to come out on top, and maybe bulk is an inaccurate proxy for more significant matters, such as the number of synapses and nerve conduction velocities.
There’s also a growing amount of literature that takes genomic approaches, searching for sequences that show the signatures of selection, and plucking those out for analysis. There have been some provocative results from that kind of work, finding some candidate genes like ASPM, but another of the lessons of that kind of work seems to be that evolution has been working harder on our testis-specific genes than on our brains.
The encouraging part of the paper is that the authors advocate expanding our search for the correlates of intelligence with another group of organisms with a reputation for big brains, but brains that have evolved independently of vertebrates’. You know what I’m talking about: cephalopods!
The Cephalopoda are an ancient group of mollusks originating in the late Cambrian. Ancestors of modern coleoid cephalopods (octopus and squid) diverged from the externally-shelled nautiloids in the Ordovician, with approximately 600 million years of separate evolution between the cephalopod and the vertebrate lineages. The evolution of modern coleoids has been strongly influenced by competition and predatory pressures from fish, to a degree that the behavior of squid and octopus are more akin to that of fast-moving aquatic vertebrates than to other mollusks. Squid and octopuses are agile and active animals with sophisticated sensory and motor capabilities. Their central nervous systems are much larger than those of other mollusks, with the main ganglia fused into a brain that surrounds the esophagus with additional lateral optic lobes. The number of neurons in an adult cephalopod brain can reach 200 million, approximately four orders of magnitude higher than the 20-30,000 neurons found in model mollusks such as Aplysia or Lymnaea. Cephalopods exhibit sophisticated behaviors a number of studies have presented evidence for diverse modes of learning and memory in Octopus and cuttlefish models. This learning capacity is reflected in a sophisticated circuitry of neural networks in the cephalopod nervous system. Moreover, electrophysiological studies have revealed vertebrate-like properties in the cephalopod brain, such as compound field potentials and long-term potentiation. Thus cephalopods exhibit all the attributes of complex nervous systems on the anatomical, cellular, functional and behavioral levels.
Unfortunately, the purpose of the paper is to highlight an unfortunate deficiency in our modern research program: there is no cephalopod genome project. The closest thing to it is an effort to sequence the genome of another mollusc, Aplysia, which is a very good thing—Aplysia is a famous and indispensable subject of much research in learning and memory—but it’s no squid. The authors are advocating additional work on another animal, one with a more elaborate brain.
A parallel effort on a well-studied octopus or squid should provide insights on the evolutionary processes that allowed development of the sophisticated cephalopod nervous system. For example, have cephalopods undergone accelerated evolution in specific nervous system genes, as has been suggested for primates? Have specific gene families undergone expansion in the cephalopod lineage and are these expressed in the nervous system? Are there clear parallels in accelerated evolution, gene family expansion, and other evolutionary processes between cephalopods and vertebrates? Answers to these and related questions will provide useful perspectives for evaluation of the processes thought to be involved in the evolution of the vertebrate brain.
I’m all for it—let’s see a Euprymna genome project!
Jaaro H, Fainzilber M (2006) Building complex brains—missing pieces in an evolutionary puzzle. Brain Behav Evol 68(3):191-195.
While browsing through the UW Alumni magazine (yes, I read it; no, please don’t ask me for money, I’m poor), I ran across a nice quote I thought I’d share:
Imagine it like the software in a computer that is five years old…these [stem] cell lines are inherently inferior. We’re forced to focus our efforts on lines that are inherently less innovative.
Dr Anthony Blau, commenting on Bush’s veto of a bill that would open up new cell lines for research
But I like it anyway. It’s a series of charts illustrating channels of communication of science.
I appreciate the distinction made between “Average Citizen” and “Informed Citizen.” Maybe there ought to be another box interposed between “Mainstream Media” and “The Average Citizen” labeled “Fox News/Talk Radio/Other Organs of Propaganda,” though. And shouldn’t there be another arrow from “Mainstream Media” to “Informed Citizen”?
I’m teaching a course in developmental biology this term, and as part of the coursework, I’m making students blog. The idea is to force them to ferret out instances of development in popular culture, in their personal experience, and/or in their reading—I’m not asking for treatises, but simply short articles that let me know their eyes are open. This year I’m also encouraging outsiders to take a look at and comment on what they’re saying, so every week I’ll be posting a round-up of links to the developmental biology blog…and here they are:
Feel free to comment on any of them if the mood strikes you, but I am going to be particularly protective of my students, so I insist on only constructive comments. I will ruthlessly delete anything abusive or irrelevant or otherwise distracting.
One other thing we’re doing in the class is working through Carroll’s Endless Forms Most Beautiful, and before each discussion I ask the students to write up short summaries of the reading. Tomorrow, we’re going over chapter 1 and 2, and there are six different summaries up on the site right now:
A,
B,
C,
D,
E, and
F (no, those are most definitely not the grades!). I’ll usually have these things linked up a little earlier before the class, but I gave the students extra slack this time since it was a holiday week. Comments and questions there are also appreciated—if there’s something you think the students ought to bring up in the discussion, let ’em know!
One after the other, I got two requests to promote some worthy causes which need letter-writers to help out. Here they are:
Over the strong objections of Native people, wildlife biologists, sportsmen’s groups, and the general public, the Bureau of Land Management remains intent on leasing one of the most remarkable wetlands complexes on the planet. The place is the Teshekpuk Lake Special Area in the National Petroleum Reserve-Alaska (NPR-A), the largest single block of wild public land left in the United States.
On Monday, the Ohio Board of Education will hold its first fall meeting. Creationists on the board are hoping to introduce a Controversial Issues Template, which would not only allow for the teaching of intelligent design in science classrooms, but demand that teachers question global warming and highlight the religious right’s opposition to stem cell research.
Don’t just sit there! Do something!
Since we biologists were just bizarrely accused of being like a bunch of animal rights activists, I am surprised that when I read that PETA opposes experiments on gay sheep, I find myself opposing PETA and thinking that the experiments sound cool and interesting and informative. I’m also a little disgusted with the way PETA finds it necessary to lie in their criticisms.
The Next Hurrah has a thorough take-down of PETA. Particularly amusing is the statistic that the research involves 18 sheep a year, while meat-packers butcher 4 million per year…so which one do the kooky extremists of the animal rights movement go after? There is an entirely appropriate quote from Mark Twain that applies here: “To create man was a fine and original idea; but to add the sheep was a tautology.” Research that studies cute little lambs and can be tied to homosexual shibboleths of both the right and the left sounds like the perfect scapegoat to lead more people to contribute to their cause; damning lamb chops and mutton just doesn’t push the right buttons.
