evolution
evolgen | April 8, 2008Us dudes are always accused of thinking with our dicks. Perhaps it's because the genes expressed in our brains are similar to those expressed in our 'nads:
Among the 17 tissues, the highest similarity in gene expression patterns was between human brain and testis, based on DDD and clustering analysis. Genes contributing to the similarity include ribosomal protein (RP) genes as well as genes involved in transcription, translation and cell division.
The authors of the paper allege that their result has something to do with speciation. They even claim, "Brain is the most important tissue in…
voltagegate | April 8, 2008It has been claimed in the past that birdfeeders were bad for the environment, and now a couple of researchers are looking into published literature on whether or not birdfeeders significantly disrupt the ecology and future evolution of birds.
The PR from SD is basically highlights of the researchers' survey, including indications that birds may get "trapped" in inhospitable areas by the surplus of food or that birdfeeders can disrupt a bird's natural breeding/feeding cycle throughout the year.
This review seems to be a jumping off point for more research:
"Changing the natural dynamics of…
mikethemadbiologist | April 8, 2008I've recently written a couple of posts about how evolution is used in medicine. Randolph Nesse and Stephen Stearns in Evolutionary Applications have written an article about evolutionary medicine. Here's one part that provides some additional examples (italics mine):
Some of the most useful applications of evolution often do not use evolutionary theory directly; instead they use technologies developed by evolutionary biologists. In particular, methods for reconstructing phylogenies are being applied to genetic data with very practical results. HIV is especially susceptible to such methods…
edyong | April 7, 2008Our bodies are serviced by a huge workforce of enzymes, which speed up the chemical reactions that rage within our cells. These enzymes have been crafted into a vast array of shapes and functions over millions of years of evolution but new ones can be generated on a microchip using the same principles.
Early attempts to design proteins from scratch resulted in fairly crude enzymes that were outperformed by nature's more elegant and finely-tuned efforts. Scientists have since developed more efficient artificial enzymes using the same evolutionary principles that generated naturally occurring…
gregladen | April 6, 2008
Grrrrrrrrrrrrr....
Welcome to the Lucky 13th Edition of The Boneyard ... the Web Carnival about Bones and Stuff.
"The Boneyard is a blog carnival covering all things paleo, from dinosaurs to pollen to hominids and everywhere in between. It's held every two weeks (the 1st and 3rd Saturday of the month), traveling around to a different blog for each installment, connecting some of the best blogging on ancient life."
The previous edition of The Boneyard is here, at Dragon's Tales. The next edition of The Boneyard will be Here at Archaeozoology. If you would like to submit an entry to the next…
pharyngula | April 6, 2008[Since I had to fly away early this morning and missed all these talks, I had to rely on regular commenter DanioPhD to fill in the gaps … so here's her summary:]
This morning's final series of talks each focused on a different phylum, but the unifying theme was one of bridging the processes of microevolution and macroevolution. The first talk after breakfast (and a long night of Scotch-drinkin' and story-swappin' prior to that) was Bernie Degnan of the University of Queensland. He summarized his work on Amphimedon queenslandica, a sponge species developed as a model of a representative…
razib | April 6, 2008We've talked before on ScienceBlogs about the extinction risk to Tasmanian Devils because of contagious cancer. Well, perhaps there's a light at the end of this population tunnel, Hope over Tasmanian Devil cancer:
The world's largest marsupial carnivore is facing extinction from a mystery facial cancer.
But scientists say Cedric appears to be naturally resistant to the contagious tumours which have killed half the devil population in Tasmania.
Cedric is the first Tasmanian Devil to have shown any immunity from the disfiguring disease.
I'll be entirely honest here: I'm not surprised. I just…
awild | April 6, 2008
How does a newly speciating ant prevent backcrossing with its parental species? A new study in the journal Evolution by Schwander et al. investigates four hypotheses using the Pogonomyrmex rugosus/barbatus hybrid speciation system, finding support for three of them. Apparently the daughter species maintains its genetic distinctness from a parent species by mating at a different time, mating preferentially with its own species, and by having a much lowered ability to produce viable offspring.
In my opinion, the story of these hybrid harvester ant species is among the most interesting pieces…
pharyngula | April 5, 2008I'm going to get off a quick summary of this afternoon's talks, then I have to run down to the poster session to find out what the grad students have been doing. Are we having fun yet? I'm going to collapse in bed tonight, and then unfortunately I have to catch an early flight back home, so I'm going to miss a lot of cool stuff tomorrow.
First up after lunch was Deneen Wellik, who summarized her work with Hox genes and patterning the vertebrate axial skeleton. I'm spared some effort here — I already wrote up her paper, so read that for the whole story. In short, one of the confounding things…
pharyngula | April 5, 2008My brain is most wonderfully agitated, which is the good thing about going to these meetings. Scientists are perverse information junkies who love to get jarred by new ideas and strong arguments, and meetings like this are intense and challenging. I've only got a little time here before the next session, so let me rip through a short summary of my morning.
Hopi Hoekstra talked about Golden mice in them thar hills: the molecular basis of crypsis in Nebraskan deermice. This was an excellent example of the kind of approach Coyne advocated the previous evening: she has a very cool system in mice…
pharyngula | April 4, 2008So here I am at the IGERT Symposium on Evolution, Development, and Genomics, having a grand time, even if I did get called out in the very first talk. There were two keynote talks delivered this evening, both of which I was anticipating very much, and which represented the really good side of science: two differing points of view wrestling with each other for consensus and for testable, discriminating differences. They also had dueling t-shirts.
Here's the argument in brief. The functional part of the genome can be roughly broken down into two components: the coding regions, or the actual bit…
evolvingthoughts | April 4, 2008
Evilunderthesun is a German language blog that recently did two things: totally demolished the "Nazism was caused by Darwin" trope, with generous quoting of mich, and educated me that the word for April fool in German is Aprilschmerz, which I really like.
Tometheus (Prometheus' and Epimetheus' little brother, responsible for bringing egotism from the gods, I think) quotes my list as one of its favourite Aprilschmerzen.
It's good to be appreciated...
gregladen | April 4, 2008A very important and truly wonderful paper in Nature described a tour-de-force analysis of the Mammalian Evolutionary Record, and draws the following two important conclusions:
The diversification of the major groups of mammals occurred millions of years prior to the KT boundary event; and
The further diversification of these groups into the modern pattern of mammalian diversity occurred millions of years later than the KT boundary event.
The KT boundary event is the moment in time when a ca. 10 km. diameter object going very fast hit the earth in the vicinity of the modern Yucatan,…
mikethemadbiologist | April 2, 2008Over at denialism blog, PalMD has two posts which, to me anyway, are related. The first has describes how sexually transmitted diseases (STDs) are actually treated with antibiotics:
After hours, we see walk-ins, and that's where the STD fun really begins. For whatever reason, I see STDs daily at the walk-in clinic, but almost never in my private practice. Most commonly, we see only one partner, and, at least in my state, treatment of the absent partner is prohibited. Basically, we only get one shot at folks, and we don't have access to rapid tests. So what do we do? We order a lot of "…
mikethemadbiologist | April 2, 2008When I started blogging, I never (EVAH!) thought I would describe the biology of E. coli with a Tolkein poem:
All that is gold does not glitter,
Not all those who wander are lost;
The old that is strong does not wither,
Deep roots are not reached by the frost.
From the ashes a fire shall be woken,
A light from the shadows shall spring;
Renewed shall be blade that was broken,
The crownless again shall be king.
I'm referring, of course, the spinach outbreak strain of E. coli O157:H7. You know, this one:
It turns out that this particular strain of E. coli O157:…
awild | April 1, 2008
If you watch this video about a new technology for visualizing insect fossils hidden in opaque amber, pay special attention around 0:36-0:44. There's a brief 3D image of what is clearly a well-preserved sphecomyrmine ant. The clip is excerpted from a detailed demonstration here, showing the insect in all its glory (warning: 57MB!). It's among the most detailed glimpses of a Sphecomyrmine yet.
Why is this ant interesting? Sphecomyrminae is in many respects a classic piece of evidence for the wasp ancestry of ants. It is an extinct Cretaceous subfamily that shows a few characteristics of…
edyong | April 1, 2008You could argue that life is all about cheating death and having enough sex to pass on your genes to the next generation, as many times as possible. From this dispassionate viewpoint, human reproduction is very perplexing for our reproductive potential has an early expiry date. At an average age of 38, women start becoming rapidly less fertile only to permanently lose the ability to have children some 10 years later during menopause.
From an evolutionary point of view, this decline is bizarre. Other long-lived animals stay fertile until close to the end of their lives, with elephants…
evolvingthoughts | March 31, 2008
David Williams sent me this snippet of Ursula Le Guins' review of Salman Rushdie's The Enchantress of Florence: A Novel:
Some boast that science has ousted the incomprehensible; others cry that science has driven magic out of the world and plead for "re-enchantment". But it's clear that Charles Darwin lived in as wondrous a world, as full of discoveries, amazements and profound mysteries, as that of any fantasist. The people who disenchant the world are not the scientists, but those who see it as meaningless in itself, a machine operated by a deity. Science and literary fantasy would seem…
loom | March 31, 2008These biologists are holding out on me.
I've been writing about biology for quite some time now, and sometimes I think I've got a pretty good sense of the scope of life. Neurosurgeon wasps--got it. Eels with alien jaws--check. And then I stumble across something new, or should I say, new to me.
This week's revelation is androgenesis. Androgenesis is what happens when kids get all their genes from their father. Normally humans and other animals produce offspring by combining DNA from both mother and father, an arrangement that's often the case in plants as well. Both sperm and eggs only get…
evolvingthoughts | March 31, 2008
I have yet to see the film Expelled, because it hasn't come to Australia yet, but I have become absolutely convinced that Ben Stein is correct. Darwinism causes antisemitism. I have therefore conveniently listed all the cases known of this below the fold. I'll stick with those in which Jews were killed or which led up to justifying such killings. I have of course had to correct the Darwinian fake history, which I have done with strikeouts and italic insertions so you all can see how perfidious these Darwinian revisionists are.
38CE: Thousands of Jews were killed in Alexandria, under Darwin…