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The eyes have it

by Donald Prothero on Aug 08 2012

Since the days of Darwin, eyes and evolution have been an irresistible topic for scientists and amateur authors alike. British biologist St. George Jackson Mivart was initially a supporter of Darwin, but when his Catholic religion caused conflict with Thomas Henry Huxley in 1871, he changed to a critic. Mivart’s critique focused on the issue of the perfection of the human eye and how he could not possibly imagine how it could have evolved by natural selection and random chance (a point still raised by creationists today who know nothing about comparative biology). In later editions of On the Origin of Species, Darwin specifically addressed Mivart’s criticism and carefully explained how the incipient stages of complex structures like the eye could be useful, and could have evolved by small steps; it did not require a giant leap to the complexity to develop the human eye. As Darwin first showed, nature is full of examples of every kind of photoreceptor, from simple light-sensitive cells to eyespots to simple eyes with no lenses, to a variety of solutions of seeing with more and more complex eyes. Once you arrange these solutions in an array, it is only a small step from one to the next, more complex eye. (Indeed, many animals actually show this transition during their embryonic development as their eyes change, and in some organisms, the eyes develop differently in males and females). In fact, the passages where Darwin talks about the eye are one of the most frequently “quote mined” by creationists trying to distort Darwin’s meaning, because they quote only the beginning of the paragraph were Darwin is setting up the creationist position in order to shoot it down the in the rest of the passage (which creationists never quote). In full context, the quote reads:

To suppose that the eye, with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, seems, I freely confess, absurd in the highest possible degree.[This is where the creationist quote-mine usually ends]. Yet reason tells me, that if numerous gradations from a perfect and complex eye to one very imperfect and simple, each grade being useful to its possessor, can be shown to exist; if further, the eye does vary ever so slightly, and the variations be inherited, which is certainly the case; and if any variation or modification in the organ be ever useful to an animal under changing conditions of life, then the difficulty of believing that a perfect and complex eye could be formed by natural selection, though insuperable by our imagination, can hardly be considered real. How a nerve comes to be sensitive to light, hardly concerns us more than how life itself first originated; but I may remark that several facts make me suspect that any sensitive nerve may be rendered sensitive to light, and likewise to those coarser vibrations of the air which produce sound. (Darwin, On the Origin of Species, 6th ed., 1872, 143-144).

The rest of Darwin’s chapter then goes into great length describing the full range of photoreceptor solutions in the animal kingdom—none of which any creationist ever bothers to read, let alone address. (continue reading…)

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Out of the Frying Pan and Into…?

by Mark Edward on Aug 06 2012

I Was One of America’s Top Psychics — and Like All of Them, A Complete Fraud!

So reads the banner at Alternet.com Yep – that’s me folks! As reported in a series of short excerpts on Alternet, “PSYCHIC BLUES” is starting to get some positive traction – and ruffle some woo feathers too. Not a peep from “the skeptic community” but plenty of good feedback at Amazon and Alternet. (continue reading…)

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Health Information on the Internet

by Steven Novella on Aug 06 2012

Most Americans have used the internet to look for health information (a recent survey reports that 59% of adults have searched for health information on the net). Yet there are serious concerns about the accuracy and reliability of that information. There have therefore been many studies looking at the accuracy of health information, and not surprisingly the results are concerning.

Most of these studies pick a specific topic and then have one or more experts on that topic review websites obtained through specific search terms. For example, a British study looking at the treatment of fever in children concluded:

Only a few web sites provided complete and accurate information for this common and widely discussed condition. This suggests an urgent need to check public oriented healthcare information on the internet for accuracy, completeness, and consistency.

(continue reading…)

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Truth Hurts

by Brian Dunning on Aug 02 2012

So goes the old saying, anyway. Shira Lazar and I found that out the hard way, when director Ryan Johnson turned us into test dummies. The idea for this pilot series episode was to see if binaural beats — audio files that purport to change your brain function — work as advertised.

Shira tested a binaural beat file that says it will make you drunk, while I did the real thing. I went into the hotel bar and got hammered with 9 drinks of Patron 1800 tequila, while Shira repaired to the hotel spa for some hot tub soaking with her iPod. We did before and after tests at the local Boomers amusement park – testing miniature golf skills, climbing, go karts, and batting cages. We did it sober, and drunk. Did the binaural beats affect Shira’s performance as much as it did mine? Watch to find out. (continue reading…)

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Hell ride to a supervolcano

by Donald Prothero on Aug 01 2012

One of the great joys of being a geologist is that every summer I try to escape the heat waves of July and August by doing field research in some place with a nicer summer climate. In the late 1990s until 2003, I was funded by the NSF and the Petroleum Research Fund of the American Chemical Society to do paleomagnetic dating on the Cenozoic marine rocks of the Pacific Coast. This meant several weeks each summer in coastal Oregon, Washington, or California, to work during their dry season when the outcrops along creek beds were at their most exposed—and timed for the lowest summer tides, so we could also sample outcrops along beach cliffs. But in the past 10 years, I’ve been doing research nearly every summer up in the high elevation (camping at 8800 feet) of the San Juan Mountains of southwest Colorado. The summer weather here is delightful: dry and in the low 80s at the hottest in the daytime, cooler in the mountains, and nothing like the 100-degree heat waves we hear about on the news scorching the rest of the country.

This particular summer we finally visited one of the great geologic sights of North America, the nearly inaccessible Wheeler Geologic Area in the La Garita Wilderness, north of South Fork and Creede, Colorado. It is one of the few remaining exposures of one of the largest supervolcano eruptions in the last 65 million years. First discovered by Capt. George M. Wheeler, who surveyed it for the U.S. Army in 1874, it is a spectacular cliff amphitheater with huge erosional “hoodoos” (pinnacles and columns) of volcanic rock. It was made Colorado’s first national monument in 1908, but then demoted in 1950 when the government decided not to spend money to make it more accessible, and instead incorporated into the La Garita Wilderness Area. It rivals more famous parks, such as Bryce Canyon in Utah, for its scenic beauty. The big difference, however, is accessibility. Whereas Bryce is visited by millions of people each year, and had roads, trails, railings on the overlooks, and many tourist facilities, Wheeler is almost completely undeveloped. First you must drive almost 20 miles up a decent gravel road from 8000 feet to 11,000 feet to the site of an old abandoned sawmill near Pool Table Mountain. Then there is another 13 miles over one of the worst “roads” I’d ever traveled on, followed by a hard hike at over 12,000 feet in elevation, to reach it. We brought along four-wheel ATVs to attempt the trip, since the “road” is brutal to vehicles and even a Jeep has trouble on the numerous deep flooded washouts and piles of huge rocks that litter the “road”.

(continue reading…)

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Logging In

by Mark Edward on Jul 31 2012

“Easy as Falling Off a Log”

So you thought that petrified tree trunk in your back yard was just in the way of your koi pond huh? Think again. You may be sitting on a goldmine. From the well-respected ”BS Historian” comes this gem: (continue reading…)

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The Colorado Massacre, Gun Control,
and the Law of Large Numbers

by Michael Shermer on Jul 31 2012

It is too soon to tell what the motive was behind the accused James Holmes’ mass murder in a movie theater in Aurora, Colorado, especially now that he has stopped talking to the authorities in charge of his case. Reports about his personality, thoughts, and behaviors from friends, fellow students, professors, and the police are conflicting. He was smart, brilliant in fact. No, he wasn’t; he was a sub-standard student who dropped out of his doctoral program at the University of Colorado after failing a preliminary exam. He was a quiet man who said nothing to indicate he was on the verge of cracking. Also not true; he left an incoherent and rambling voice message on the phone service of a gun club he wanted to join, the owner of which noted: “It was this deep, guttural voice, rambling something incoherent. I thought, ‘What is this idiot trying to be?’.” He rigged his apartment with explosive devices but then warned the police about them after his capture. Initial reports described the event as spontaneous and random, but he mailed a notebook to his psychiatrist at his university describing in detail with diagrams precisely what he (pre)planned to do.

It may be months before we have any clue to his mind and motive. And short of something obvious like a brain tumor pressing against his amygdala (the brain’s emotion center)—similar to that in the brain of Charles Whitman, the University of Texas bell tower shooter who in 1966 killed 14 people and wounded 49, including himself, after leaving a note to authorities to autopsy his brain because he felt there was something wrong—we may never know the motive behind James Holmes murderous actions.

We do know something for certain, however, and that is that this will happen again…and again and again. The reason is (continue reading…)

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The Seat of Consciousness

by Steven Novella on Jul 30 2012

Where is the “seat of consciousness” in the brain? This is often presented as an enduring mystery of modern neuroscience, and to an extent it is. It is a very complex question and we don’t yet have anything like a complete answer, or even a consensus. The question itself may contain false assumptions – what, exactly, is consciousness, and perhaps what we call consciousness emerges from the collective activity of the entire brain, not a subset. Perhaps every network in the brain is conscious to some degree, and what we experience as our consciousness is the aggregate effect of many little consciousnesses.

One way to approach this question (really a set of related questions) is to study different mental states – altered states of consciousness. How those differences relate to brain function are likely to tell us something about the contribution of that brain function to full wakeful consciousness.

A new study by scientists from the Max Planck Institutes of Psychiatry in Munich and for Human Cognitive and Brain Sciences in Leipzig and from Charité in Berlin attempts to do just that. They have studied the brain activity of those in normal dreaming and in a so-called lucid dreaming state.

(continue reading…)

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a giant cause at the giant’s causeway

by Donald Prothero on Jul 25 2012

Susanna Drury’s famous 1739 image, “A View of the Giant’s Causeway: East Prospect”

As we continually battle the efforts of creationists to tamper with science education in the U.S., and watch the dismaying polls that show about 40% of Americans agree with creationist positions, we try to take comfort in the fact that creationism has virtually no standing in most of Europe, which is also among the most secular regions in the world. Most attempts to push fundamentalist creationism in the more secular countries (especially those of northern Europe, including the Scandinavian countries, Germany, Holland, and the UK) have met with little or no success, and the number of creationists in those countries are minuscule. Even the predominantly Catholic parts of Europe don’t deal with much creationism, either, since the Catholic Church has long ago come to some sort of truce with evolution (although still reserving the right to make pronouncements about the soul and humanity’s animal nature). Nonetheless, even a small band of determined creationists can make a lot of trouble and influence policy way out of proportion to their numbers.

The latest controversy of this sort involves a famous geologic feature on the coast of County Antrim in northeastern Ireland known as Giant’s Causeway. Its discovery and description are important pieces in the early history of geology, as many different people in the 1700s puzzled over it and tried to explain it in the context of Noah’s flood, or gave even more fantastic explanations. There were numerous Irish legends about it. One account claims that Finn McCool (Fionn mac Cumhaill) built it as a bridge to Scotland to fight the legendary Scottish warrior Benandonner. According to different versions of the legend: (continue reading…)

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Stopping for “Red Lights?”

by Mark Edward on Jul 23 2012

Bobby De Niro Has The Gift?

Saturday afternoon found me finally getting the chance to see the latest psychic thriller, “Red Lights.” While I have huge reservations about the final outcome of this trendy look at people who claim to be psychic and those of us who go after them, I will review it here without spoilers.  I ultimately must recommend this film for skeptical minded individuals for reasons that are totally unintentional by the film’s writers, director and producers. (continue reading…)

THIS ARTICLE HAS 11 COMMENTS

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