evolution
evolvingthoughts | January 21, 2007In an inadvertently, or perhaps deliberately, funny abstract, D. Osorio notes that there's a role for spam in insect evolution.
Spam and the evolution of the fly's eye.
Osorio D.
School of Life Sciences, University of Sussex, Brighton BN1 9QG, UK.
The open rhabdoms of the fly's eye enhance absolute sensitivity but to avoid compromising spatial acuity they require precise optical geometry and neural connections. This neural superposition system evolved from the ancestral insect eye, which has fused rhabdoms. A recent paper by Zelhof and co-workers2 shows that the Drosophila gene spacemaker (…
razib | January 21, 2007Over at Bora's place he talks about a paper on group selection. In regards to the scientific idea and its broad relevance to evolutionary biology, I am mildly skeptical. That being said, this comment drew my attention:
While endorsing DS Wilson's Unto Others, Richard Lewontin mentioned an unsavory aspect of group selection (NYROB, 10/22/98): namely, war is a mechanism of the differential survival and reproduction of whole groups. Out-group aggression goes hand in hand with in-group cooperation. It is very advisable to be mindful of the Naturalistic Fallacy when considering group selection.…
oracknows | January 18, 2007Geez, I might as well just put a paper bag over my head right now around my fellow ScienceBloggers.
You've heard me lament before about the woeful ignorance about biology and evolution common among all too many doctors. (You haven't? Well check here, here, here, and here.) Heck, you've even heard me lament about it just a few days ago, my irritation being piqued by a physician by the name of Dr. Geoffrey Simmons.
Now, as if to rub my face in it, Dembski's crew over at Uncommon Design have made me aware of an orthopedic surgeon named David A. Cook, M.D., who's adding to my embarrassment. As…
hrynyshyn | January 18, 2007PZ Myers rarely writes anything I find objectionable, but today he is so bang on that I feel compelled to share it with those few readers of mine who might not be regular visitors to Pharygula.
PZ basically wants to give young students the benefit of the doubt, rather than assuming they can't handle anything verging on ethically or intellectually challenging. Responding to Francis Collins' suggestion that kids of fundamentalist parents can't handle it when their world view collides with scientific reality, he writes:
As young people's crises go, the conflict between science and religion is a…
loom | January 17, 2007Mark Twain once discovered to his horror that his story "The Jumping Frog of Calaveras County" had been hideously translated into French. He went so far as to publish the original story, the translation, and his own retranslation of the French back to English to show just how badly it had been abused. "I claim that I never put together such an odious mixture of bad grammar and delirium tremens in my life," he declared.
I was reminded of Twain's experience when a reader drew my attention to a creationist attack published yeserday against an article I recently wrote for National Geographic. It…
jrosenhouse | January 16, 2007Chris over at Mixing Memory has this post about cognitive factors that can make it difficult for children to learn about evolution. This is from his conclusion:
So that's my contribution. I've presented three factors that make the job of biology teachers more difficult when they're trying to teach evolution, either to children or adults.
Intuitive theism, in which our intuitions lead us to make design inferences about complex kinds or under conditions of uncertainty; intuitions that can be reinforced culturally to an extent that it may be almost impossible to overcome them by the time we…
razib | January 16, 2007There is news about a skull which is about 40,500 years old found in Europe that exhibits a hybrid Neandertal-Modern morphology:
However, there were some important differences: apparently independent features that are, at best, unusual for a modern human. These included frontal flattening and exceptionally large upper molars with unusual size progression which are found principally among the Neanderthals.
...
Prof Chris Stringer of the Natural History Museum, London, commented on the PNAS paper's suggestion of interbreeding: "How often it happened and its importance to the bigger picture of…
evolgen | January 15, 2007T-Rex thinks he's eliminated zombies with logic. The basic idea: Zombies depend on human brains to survive, but they also must bite humans (turning them into zombies) to create more zombies. If zombies were really good at catching humans and eating their brains, there would be no more humans and the zombie population would die off. Conversely, if the zombies had trouble getting to the human brains, they could convert humans into zombies (by biting them without eating their brains), but they would starve due to brain deprivation.
Anders Sandberg disagrees, and he's done the simulations to back…
pharyngula | January 14, 2007
Q: What unique organ is found only in mammals, but not in fish, amphibians, reptiles, or birds?
The title and that little picture to the left ought to be hint enough, but if not, read on.
A: The vagina. Aren't we lucky?
There's an old joke going around about poor design: what kind of designer would route the sewer pipes right through the center of the entertainment center? It's a good point. It doesn't make sense from a design standpoint to have our reproductive and excretory systems so intimately intermingled, but it does make a heck of a lot of sense from a purely historical point of view…
mikethemadbiologist | January 14, 2007So those who oppose global warming are using the same strategy as the creationists: teach the 'controversy.'
This week in Federal Way schools, it got a lot more inconvenient to show one of the top-grossing documentaries in U.S. history, the global-warming alert "An Inconvenient Truth."
After a parent who supports the teaching of creationism and opposes sex education complained about the film, the Federal Way School Board on Tuesday placed what it labeled a moratorium on showing the film. The movie consists largely of a computer presentation by former Vice President Al Gore recounting…
oracknows | January 14, 2007I've lamented numerous times (1, 2, 3, 4, 5) about the sometimes painful ignorance of biology and evolutionary theory that's all too common among my fellow physicians, an ignorance that leads to truly embarrassing forays into the "debate" over the pseudoscience of "intelligent design" versus the real science of evolution, an example of which includes the Physicians and Surgeons for Scientific Integrity's idiotic petition expressing "skepticism" about evolution.
Here we go again. This time, I learn of a pro-"intelligent design" book for children written by....a physician!
Note the author:…
clock | January 13, 2007I have just realized that I keep mentioning David Sloan Wilson a lot (see the list of links below), always in a positive light as I think he is one of the pioneers of modern evolutionary theory (as soon as those drunk on Williams 1966 and Dawkins' opus retire or die) but have never really written a good post on group selection. I'll have to do this one day soon - that may be my contribution to the Basic Concepts collection.
Anyway, Wlison just gave a talk in which he presented my favourite example of the test of group selection - in chickens:
Two experiments using chickens show another…
evolvingthoughts | January 12, 2007
This is the first in an irregular series of basic concepts in science, that I suggested to the Seed Bloggers we might do from time to time. If anyone wants to suggest a revision, because I got it wrong or am unclear, make a comment - this will be revised to make sure it is OK.
Clade: this term of art is a new one in biological systematics, or the science of classification, or taxonomy. The word has given its name to a new science of classification: cladistics, which is properly known as phylogenetic systematics.
A clade is, simply expressed, any branch (Greek: klados) of the evolutionary…
grrlscientist | January 12, 2007
Rafflesia arnoldii flower.
Image: source.
The relatives of the largest and smelliest flower in the world, Rafflesia, have finally been found. This family, the Euphorbiaceae -- known for some of the smallest flowers in the world, too -- includes the poinsettia, Irish bells, the rubber tree, and castor oil plant.
The plant is found on the Indonesian island, Sumatra. It is a parasite that steals nutrients from another plant while deceiving insects into pollinating it. Its blood-red flowers can weigh as much as 7 kilograms (15 pounds ) and they smell like decaying flesh. And they even can…
pharyngula | January 12, 2007What's a philosopher doing writing about science? Willikins has a short article on the idea that bioturbation was a major factor in the Cambrian explosion. I can go with that: the Cambrian and pre-Cambrian seem to have been times when the sea floor was covered with algal mats, and the successful animal forms were grazers who scraped the surface and worms that burrowed through them. Along with changes in atmospheric oxygen, the radical remodeling of the marine substrate were the major biologically induced changes in the environment.
purepedantry | January 12, 2007From the NY Times:
An international team of researchers reported yesterday that the age of the South African skull, which they dated at about 36,000 years old, coincided with the age of the skulls of humans then living in Europe and the far eastern parts of Asia, even Australia. The skull also closely resembled skulls of those humans.
The timing, the scientists and other experts said, introduced independent evidence supporting archaeological finds and recent genetic studies showing that modern humans left sub-Saharan Africa for Eurasia between 65,000 and 25,000 years ago; probably closer to…
hrynyshyn | January 12, 2007Well, technically, not Seattle, but the exurbian outpost of Federal Way, Wash., where the "School Board on Tuesday placed what it labeled a moratorium on showing the film." The film in question is Laurie David's An Inconvenient Truth, with which I am sure we're all familiar. First, I have to declare a conflict of interest, being a member of Al Gore climate change troops. But really, what does this story say about how the Federal Way school board thinks of its students if those students can't be trusted to watch a movie about the science and social implications of climate change?
Apparently,…
evolvingthoughts | January 11, 2007
Quick... what was Darwin's most popular book? If you answered The Origin of Species, you were wrong. It was his last book, published the year before he died, The Formation of Vegetable Mould Through the Action of Worms With Observation of Their Habits. Darwin noted when he was beginning his career that worms churned up soil, causing heavier objects to sink slowly in the soil. He noted that all soil had passed through the alimentary duct of worms. It started off a fashion of cultivating worms by gardeners that continues to the present day.
Now called "bioturbation", this process has…
evolvingthoughts | January 11, 2007
One of the more famous events in the development of evolutionary biology was the shift from the linear notion of horse evolution proposed by E. D. Cope O. C. Marsh and T. H. Huxley in the 19th century to the "bushy" model of horse evolution in the middle of the 20th. But not all branches of the bush were found.
Now, an eight year old boy fossil hunting with his parents in California Nevada has found some crucial fossils of small three toed horse ancestors. I hope he ends up doing more of this...
UPDATE: Josh Rosenau has a corrected and expanded post on this. He actually asked an expert,…