25 January 2010
Who's Afraid of the HPV Vaccine?
And again, my daughter has the vaccines, even though she is on the autism disorder spectrum. And as a responsible parent, she will be made aware of all aspects of human sexuality, and have all the tools available to her to make the smart decisions that I hope she will make. Especially considering that abstinece only teaching has time and time again been proven to be a dismal failure. Anyway, here is what I consider an interesting article on science, psychology, and health.
Who's Afraid of the HPV Vaccine?
A new study concludes that people tend to match their risk perceptions about policy issues with their cultural values, which may explain the intense disagreement about proposals to vaccinate elementary-school girls against human-papillomavirus (HPV). The study also says people's values shape their perceptions of expert opinion on the vaccine.
HPV is a widespread disease that, when sexually transmitted, can cause cervical cancer. In October of 2009, the Center for Disease Control and Prevention (CDC) recommended that the vaccine be given to all girls ages 11 or 12. However, the recommendation has been mired in controversy, and so far adopted in only one state and the District of Columbia.
An online experiment involving more than 1,500 U.S. adults reveals that individuals who have cultural values that favor authority and individualism perceive the vaccine as risky, in part because they believe it will lead girls to engage in unsafe sex. But individuals with cultural values that favor gender equality and pro-community/government involvement in basic health care are more likely to see the vaccine as low risk and high benefit.
The study was funded by the National Science Foundation (NSF) and is being published online this week in the journal Law and Human Behavior. It found that people exposed to unattributed, balanced information about HPV vaccines tended to produce something called "biased assimilation," a phenomenon in which culturally-identifiable groups draw opposing conclusions and become more divided rather than less divided as they consider evidence.
But when biased assimilation was compared to another survey result, researchers were surprised. "An even bigger effect for all subjects was the perceived values of experts," said Yale University law professor Dan Kahan referring to another part of the experiment in which arguments about the vaccine were matched with fictional experts.
Researchers designed fictional, but culturally identifiable advocates to be seen by respondents as holding opposing and culturally distinct values. The researchers devised the "advocates" to be seen as holding pro-authority and individualistic, or pro-community and pro-equality worldviews.
When views about HPV vaccines came from sources respondents believed shared their values, individuals tended to be more willing to accept the information. But when it came from an expert whom they perceived held values different from theirs, the information was not accepted. In the first instance, respondents perceived the experts to have cultural credibility and trustworthiness, but when respondent values differed from the experts, the experts were perceived to lack cultural credibility.
As a result, when experts thought to hold pro-authority and individualistic values asserted the vaccine was risky, respondents who held the same values agreed with them. When other experts who were thought to hold egalitarian and pro-community values argued that it was safe, respondents who held the same values agreed with them, intensifying overall disagreement about use of the vaccine.
"This is what the debate in public looks like," said Kahan, who led the study. "Basically, people who hold one set of values see experts with whom they identify as reinforcing their views."
Nevertheless, when experts who held pro-authority and individualistic values asserted that the vaccine was safe, and experts perceived as holding egalitarian and pro-community values argued it was risky, subjects with those values tended to moderate their original viewpoints and give consideration to an opposing viewpoint, because the information came from someone they perceived shared their values.
The study is the most recent in a series researchers have conducted with NSF support to test the "cultural cognition thesis:" the idea that because individuals can't easily judge risks when it comes to evaluating complicated or disputed policy issues, they rely on beliefs grounded in cultural ideology to help them. Previous findings have shown cultural cognition thesis explains disagreements over the risks of private gun ownership, conflict over the risks of novel sciences like nanotechnology, and the relatively low perception of various risks displayed by white males relative to other groups.
The Food and Drug Administration used "fast track" procedures to approve the HPV vaccine in 2006, and a CDC committee recommended universal vaccination of school girls shortly thereafter. In September 2009, the CDC approved an HPV vaccine for males ages 9 to 26 for prevention of genital warts, but stopped short of recommending mandatory vaccinations. The CDC's Advisory Committee on Immunization Practices plans to look at the vaccine's effectiveness in preventing HPV-related cancers in males at its next session this February.
"We hypothesized that 'cultural credibility' would have an effect," said Kahan. "But we didn't expect it to be as large as it turned out to be."
From previous studies, the researchers knew that "biased assimilation" would have an effect, perhaps even a larger effect than "cultural credibility." But, that was not the case. "Biased assimilation" divided subjects, but "cultural credibility" had the biggest impact.
"The result suggests that the identity of the source is a more important cognitive cue than how people feel about the information alone," said Kahan.
The researchers suggest that anyone who has a stake in promoting informed public debate make an effort to recruit information providers that have diverse cultural outlooks and styles. The key, they say, is to avoid creating or reinforcing any impression--even a tacit one--that a scientific debate over policy is an "us versus them" dispute
24 January 2010
Stunning New Image of Cat's Paw Nebula
Stunning New Image of Cat's Paw Nebula
ScienceDaily (Jan. 24, 2010) — ESO has just released a stunning new image of the vast cloud known as the Cat's Paw Nebula or NGC 6334. This complex region of gas and dust, where numerous massive stars are born, lies near the heart of the Milky Way galaxy, and is heavily obscured by intervening dust clouds.
Few objects in the sky have been as well named as the Cat's Paw Nebula, a glowing gas cloud resembling the gigantic pawprint of a celestial cat out on an errand across the Universe. British astronomer John Herschel first recorded NGC 6334 in 1837 during his stay in South Africa. Despite using one of the largest telescopes in the world at the time, Herschel seems to have only noted the brightest part of the cloud, seen here towards the lower left.
NGC 6334 lies about 5500 light-years away in the direction of the constellation Scorpius (the Scorpion) and covers an area on the sky slightly larger than the full Moon. The whole gas cloud is about 50 light-years across. The nebula appears red because its blue and green light are scattered and absorbed more efficiently by material between the nebula and Earth. The red light comes predominantly from hydrogen gas glowing under the intense glare of hot young stars.
NGC 6334 is one of the most active nurseries of massive stars in our galaxy and has been extensively studied by astronomers. The nebula conceals freshly minted brilliant blue stars -- each nearly ten times the mass of our Sun and born in the last few million years. The region is also home to many baby stars that are buried deep in the dust, making them difficult to study. In total, the Cat's Paw Nebula could contain several tens of thousands of stars.
Particularly striking is the red, intricate bubble in the lower right part of the image. This is most likely either a star expelling large amount of matter at high speed as it nears the end of its life or the remnant of a star that already has exploded.
This new portrait of the Cat's Paw Nebula was created from images taken with the Wide Field Imager (WFI) instrument at the 2.2-metre MPG/ESO telescope at the La Silla Observatory in Chile, combining images taken through blue, green and red filters, as well as a special filter designed to let through the light of glowing hydrogen.
23 January 2010
Justice Served
I just hope this guy rots a good long time. It's precisely this sort of deluded thinking that humans are so susceptible to. Con men and all the world's religions know that, and take advantage of it!
As Good As Dowsing
For once we have some news of rationality winning – although it took a while. Jim McCormick (pictured right), maker of the useless ADE-651 “bomb detection” device, was arrested yesterday in the UK on suspicion of “fraud by misrepresentation.” An export ban on the device will come into force next week. To which I add – about time!
It’s not as if this is new information. The ADE-651 is just the latest incarnation of a device that was previously called “The Mole,” and before that the “Quadro Tracker.” They’re all the exact same device and they have all consistently failed tests designed to see if they work. Back in October 2008 and again in November 2009, James Randi challenged the makers of the ADE-651 to apply for his million dollar prize to prove that it worked. Of course, as with all the other charlatans and quacks Randi challenges, they didn’t apply. Well, now we know why – the makers were selling these pieces of junk to the Iraqi government for $40,000 a pop or a total to date of $85 million! By my count, that’s over 2,000 not bomb detectors not detecting bombs in Iraq alone. Randi’s $ million must have seemed like small change. (I have to admit I am still a bit skeptical about this $85 million figure. It is the figure that is consistently being reported by all media, although they are probably just repeating each other, so we can’t be sure. Still, we have nothing else to go on right now. If it is confirmed it is certainly a massive fraud for such a piece of junk.)
The BBC reports that there are concerns that the devices have failed to stop bomb attacks that have killed hundreds of people. Actually, a little more than just “concerns.” There have been several successful bomb attacks in Iraq recently in areas where they were apparently relying on this bogus device:
And an attack in December killed over 120 people, prompting Iraqis to ask how the bombs could have got through the city's security.
Attention is increasingly focusing on the ADE-651, the hand-held detector now used at most checkpoints in Baghdad. [My bold.]
Get that? This useless device is used at most checkpoints in Baghdad in place of physical inspections of vehicles. Remember, this is a device that has no memory, no programming, no working electronics, no batteries and no known way it could possibly ever work. It has consistently failed to work in all controlled tests. And yet they go for $40,000 each! Over 2,000 of them.
Strangely, I find I do agree with one thing McCormick has to say about his product:
"the theory behind dowsing and the theory behind how we actually detect explosives is very similar".
Yes, dowsing and the ADE-651 are similar in that they are both complete bullshit.
Randi’s blog today has a post, Randi Responds to the Arrest of James McCormick, that includes a video of Randi explaining the history of this device and the JREF’s role in exposing it. (Although I don’t often recommend long video clips, this one with Randi is worth the time.) Astonishingly, the Quadro Tracker (which, to repeat, is the exact same product as the ADE-651) was tested back in 1995 and was described back then by the FBI as “a fraud.” Fifteen years later, McCormick gets arrested.
The Iraqi officer who appeared at a press conference with McCormick recently, Major General Jehad al-Jabiri, apparently said he did not care about the failed tests of this device. I join Randi in hoping the Iraqis investigate this Iraqi officer’s connection to the manufacturers of the device. Apparently it has been sold for $16,500 (still a rip off for something that does nothing), although it was sold to the Iraqi military for up to $60,000. Would the Major General’s bank accounts reveal kickbacks received from McCormick’s company? There would have been enough spare cash from that $85 million to pay off any number of intermediaries. Perhaps the threat of jail time (Iraqi jail – nice) would motivate the Major General finally to care if the damn thing works or not. One can only hope.
Praise should go to the JREF for doggedly exposing this fraud for at least the past 15 years, according to Randi. (Shame on the media and law enforcement for allowing it to continue, without criticism, for so long.) Don’t forget all the other frauds and charlatans who also refuse to take Randi’s $ million test because they know they would fail. (And ditto.)
Science education inoculates against religion
So I saw this blog in my feed today. I went over to read it just to see what the author had to say. At first I was hopeful that there was some correlation like IQ vs Religiosity, but I really don't see that. To me, it just seems that the more devout someone is, the more they will run away from learning about the world around them. They can't handle the fact that their impotent little god hardly has an gaps to hide in as it is, so they just cover their eyes and ears and hope nothing gets in.
Some are more active about it, and even try to keep other people who may actually want to learn (Texas Board of [un]-Education anyone?), but hopefully more and more rational people will stand up to those fucktards, and kick them to the curb where they belong. SO while this paper was somewhat positive to me, it just reminded me that it's more a result of some of these cretins willfully ignoring science, and swallowing up every lie they can find that supports their incredibly fucked up view of the world.
Science education inoculates against religion
At the back end of 2007, I wrote that science education doesn't inoculate against religion. But the time has come to indulge in a bit of revisionism.
Here's why. Darren Sherkat (who has a paper out on religious fundamentalism and verbal ability that I covered in the previous post) has also taken a look at the link with scientific knowledge. The paper isn't published yet, but he sent me the manuscript - and he's also blogged it, if you want the 'horse's mouth' version!
As before, this is an analysis of the US General Social Survey, which includes a set of 13 questions on general science topics. As you can see in the graph, people who think the Bible is a book of fables scored nearly 40% higher that those who think it is the literal word of God.
You get a similar result for people who are members of Conservative Protestant sects. What's more, it persists even after controlling for other factors that might explain the difference - like age, education, income, race, immigrant status and region.
It seems that there is something about conservative Christianity in the US that works directly against science skills. In part, this might be down to the nature of the questions.
Sherkat omitted from the analysis the question about evolution, but there are also questions about continental drift and also the Big Bang. A Young Earth Creationist, might give the wrong answer to these even though they had been taught the correct answer.
So why did I previously suggest no link between science proficiency and religiosity? Well, I looked at international student scores on science collected by PISA, and correlated these with data on how often people in those countries prayed. I didn't find any link.
But Sherkat's work suggests that the link is strongest with people who have a rather extreme attachment to their religion. So I went back and redid the analysis, using the latest religious data from the World Values Survey.
This time I looked at people who rated themselves '10' on a 10-point scale asking how important God is in their life. This is a question that really picks out the very devout.
It turns out that countries with a lot of these really devout people do very poorly at educating their children about science.
In a way that's not too surprising, because these countries also tend to be poorer and less well educated in general.
But PISA also provide data adjusted for socioeconomic differences between the countries. So this score reflects how effective countries are at educating their children on science, after taking into account their different circumstances.
The data are only available for OECD countries, but that's good because these countries are broadly similar to start with. Unfortunately, the WVS didn't collect religious data from all OECD countries, which makes the sample even smaller. But even so...
The remarkable fact is that even within this small, relatively homogenous, pool of countries there's still a significant correlation.
Although this is an ecological study (it didn't look at individual data, like Sherkat's can do with the GSS data), it does support his findings.
Either highly religious people shield their children from science, or good science education shifts people from being highly religious to a more moderate stance (or perhaps both, of course).
Either way, I'm going to have to revise my previous belief that science education and religion aren't linked!
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This article by Tom Rees was first published on Epiphenom. It is licensed under Creative Commons.
19 January 2010
Autism News
So why make a blog entry on this? Well, mostly because I haven't blogged in a while! I have been very busy with numerous things that consume more time than the day offers, and blogging was one of those extra things that just had to be prioritized out. Im sure you know how that goes.
Anyway, I haven't been over to ScienceDaily lately, so I was excited to find out more about the ability to diagnose autism. Sadly, autism is a difficult dissorder to properly and truly diagnose, and it takes quite a while. Which of course leads to the whole confusion and confirmation bias with the vaccine canard. (Just as an aside, I am a dad of an autistic child, and we all vaccinate!) Anyway, here is the article that I found:
Brain Imaging May Help Diagnose Autism
ScienceDaily (Jan. 10, 2010) — Children with autism spectrum disorders (ASDs) process sound and language a fraction of a second slower than children without ASDs, and measuring magnetic signals that mark this delay may become a standardized way to diagnose autism.
Researchers at The Children's Hospital of Philadelphia report their findings in an online article in the journal Autism Research, published January 8.
"More work needs to be done before this can become a standard tool, but this pattern of delayed brain response may be refined into the first imaging biomarker for autism," said study leader Timothy P.L. Roberts, Ph.D., vice chair of Radiology Research at Children's Hospital.
ASDs are a group of childhood neurodevelopmental disorders that cause impairments in verbal communication, social interaction and behavior. ASDs are currently estimated to affect as many as one percent of U.S. children, according to a recent CDC report.
Like many neurodevelopmental disorders, in the absence of objective biological measurements, psychologists and other caregivers rely on clinical judgments such as observations of behavior to diagnose ASDs, often not until a child reaches school age. If researchers can develop imaging results into standardized diagnostic tests, they may be able to diagnose ASDs as early as infancy, permitting possible earlier intervention with treatments. They also may be able to differentiate types of ASDs (classic autism, Asperger's syndrome or other types) in individual patients.
In the current study, Roberts and colleagues used magnetoencephalography (MEG), which detects magnetic fields in the brain, similar to the way electroencephalography (EEG) detects electrical fields. Using a helmet that surrounds the child's head, the team presents a series of recorded beeps, vowels and sentences. As the child's brain responds to each sound, noninvasive detectors in the MEG machine analyze the brain's changing magnetic fields.
The researchers compared 25 children with ASDs, having a mean age of 10 years, to 17 age-matched typically developing children. The children with ASDs had an average delay of 11 milliseconds (about 1/100 of a second) in their brain responses to sounds, compared to the control children. Among the group with ASDs, the delays were similar, whether or not the children had language impairments.
"This delayed response suggests that the auditory system may be slower to develop and mature in children with ASDs," said Roberts. An 11-millisecond delay is brief, but it means, for instance, that a child with ASD, on hearing the word 'elephant' is still processing the 'el' sound while other children have moved on. The delays may cascade as a conversation progresses, and the child may lag behind typically developing peers."
A 2009 study by Roberts and colleagues sheds light on how changes in brain anatomy may account for the delays in sound processing. The study team used MEG to analyze the development of white matter in the brains of 26 typically developing children and adolescents. Because white matter carries electrical signals in the brain, signaling speed improves when neurons are better protected with an insulating sheath of a membrane material called myelin.
In this previous study, the researchers showed that normal age-related development of greater myelination corresponds with faster auditory responses in the brain. "The delayed auditory response that we find in children with ASDs may reflect delayed white matter development in these children," said Roberts. Roberts says his team's further studies will seek to refine their imaging techniques to determine that their biomarker is specific to ASDs, and will investigate other MEG patterns found in children with ASDs in addition to auditory delays.
Grants from National Institute of Health, the Nancy Lurie Marks Family Foundation, Autism Speaks, and the Pennsylvania Department of Health supported this research. In addition, Roberts holds an endowed chair, the Oberkircher Family Chair in Pediatric Radiology at The Children's Hospital of Philadelphia. Roberts' co-authors were from Children's Hospital, including the Hospital's Center for Autism Research.
And to further debunk the anti-vax pro-disease nutters:
More Evidence That Autism Is a Brain 'Connectivity' Disorder
ScienceDaily (Jan. 11, 2010) — Studying a rare disorder known as tuberous sclerosis complex (TSC), researchers at Children's Hospital Boston add to a growing body of evidence suggesting that autism spectrum disorders, which affect 25 to 50 percent of TSC patients, result from a miswiring of connections in the developing brain, leading to improper information flow. The finding may also help explain why many people with TSC have seizures and intellectual disabilities.
Findings were published online in Nature Neuroscience on January 10.
TSC causes benign tumors throughout the body, including the brain. But patients with TSC may have autism, epilepsy or intellectual disabilities even in the absence of these growths. Now, researchers led by Mustafa Sahin, MD, PhD, of Children's Department of Neurology, provide evidence that mutations in one of the TSC's causative genes, known as TSC2, prevent growing nerve fibers (axons) from finding their proper destinations in the developing brain.
Studying a well-characterized axon route -- between the eye's retina and the visual area of the brain -- Sahin and colleagues showed that when mouse neurons were deficient in TSC2, their axons failed to land in the right places. Further investigation showed that the axons' tips, known as "growth cones," did not respond to navigation cues from a group of molecules called ephrins. "Normally ephrins cause growth cones to collapse in neurons, but in tuberous sclerosis the axons don't heed these repulsive cues, so keep growing," says Sahin, the study's senior investigator.
Additional experiments indicated that the loss of responsiveness to ephrin signals resulted from activation of a molecular pathway called mTOR, whose activity increased when neurons were deficient in TSC2. Axon tracing in the mice showed that many axons originating in the retina were not mapping to the expected part of the brain.
Although the study looked only at retinal connections to the brain, the researchers believe their findings may have general relevance for the organization of the developing brain. Scientists speculate that in autism, wiring may be abnormal in the areas of the brain involved in social cognition.
"People have started to look at autism as a developmental disconnection syndrome -- there are either too many connections or too few connections between different parts of the brain," says Sahin. "In the mouse models, we're seeing an exuberance of connections, consistent with the idea that autism may involve a sensory overload, and/or a lack of filtering of information."
Sahin hopes that the brain's miswiring can be corrected by drugs targeting the molecular pathways that cause it. The mTOR pathway is emerging as central to various kinds of axon abnormalities, and drugs inhibiting mTOR has already been approved by the FDA. For example, one mTOR inhibitor, rapamycin, is currently used mainly to prevent organ rejection in transplant patients, and Sahin plans to launch a clinical trial of a rapamycin-like drug in approximately 50 patients with TSC later this year, to see if the drug improves neurocognition, autism and seizures.
In 2008, Sahin and colleagues published related research in Genes & Development showing that when TSC1 and TSC2 are inactivated, brain cells grow more than one axon -- an abnormal configuration that exacerbates abnormal brain connectivity. The mTOR pathway was, again, shown to be involved, and when it was inhibited with rapamycin, neurons grew normally, sprouting just one axon.
Supporting the mouse data, a study by Sahin and his colleague Simon Warfield, PhD, in the Computational Radiology Laboratory at Children's, examined the brains of 10 patients with TSC, 7 of whom also had autism or developmental delay, and 6 unaffected controls. Using an advanced kind of MRI imaging called diffusion tensor imaging, they documented disorganized and structurally abnormal tracts of axons in the TSC group, particularly in the visual and social cognition areas of the brain (see image). The axons also were poorly myelinated -- their fatty coating, which helps axons conduct electrical signals, was compromised. (In other studies, done in collaboration with David Kwiatkowski at Brigham and Women's Hospital, giving rapamycin normalized myelination in mice.)
Sahin has also been studying additional genes previously found to be deleted or duplicated in patients with autism, and finding that deletion of some of them causes neurons to produce multiple axons -- an abnormality that, again, appears to be reversed with rapamycin.
"Many of the genes implicated in autism may possibly converge on a few common pathways controlling the wiring of nerve cells," says Sahin. "Rare genetic disorders like TSC are providing us with vital clues about brain mechanisms leading to autism spectrum disorders. Understanding the neurobiology of these disorders is likely to lead to new treatment options not only for TSC patients, but also for patients with other neurodevelopmental diseases caused by defective myelination and connectivity, such as autism, epilepsy and intellectual disability."
The current study was funded by grants from the National Institutes of Health, the John Merck Scholars Fund, Tuberous Sclerosis Alliance, the Manton Foundation, the Children's Hospital Boston Translational Research Program, and the Children's Hospital Boston Mental Retardation and Developmental Disabilities Research Center.
Duyu Nie was first author on the paper. Coauthors were Duyu Nie, Alessia Di Nardo, Juliette M Han, Hasani Baharanyi, Ioannis Kramvis, and ThanhThao Huynh, all of the F.M. Kirby Neurobiology Center and Department of Neurology, Children's Hospital Boston; Sandra Dabora of Brigham and Women's Hospital; Simone Codeluppi and Elena B Pasquale of the Burnham Institute for Medical Research, and University of California San Diego; and Pier Paolo Pandolfi of Beth Israel Deaconess Cancer Center.
FULL DISCLOSURE: I am also one of the administrators for the Facts, not Fantasy website. Just in case anyone was wondering. And yes, i will put this article there in the near future.
Science! It works bitches!
10 January 2010
Tim Minchin’s coming Storm
If you’re a skeptic, you probably already know about the comedy musician Tim Minchin. He is simply brilliant, writing fantastic music about critical thinking. He was at TAM London and basically owned the place.
Skepchick Tracy King is overseeing the creation of an animated version of Tim’s absolutely fantastic song "Storm", about a skeptic at a dinner party who runs into a woman who believes anything as long as it isn’t real. The song is incredible, and the animation looks to be as well: they just released the official trailer.
It’s notoriously difficult to know if a video will go viral or not, but keep your eyes on this. When it’s finished, it’ll be big.
Casey Luskin Wrong on Tiktaalik
Casey Luskin Wrong on Tiktaalik
Casey Luskin over at the Disco-Tute’s blog is getting all excited about the recent discovery of fossilized tetrapod (four footed vertebrate) footprints in Poland, dated 395 million years ago. What? The Disco-Tute is excited about new scientific discoveries? Well, yes, but only because they think it disproves evolution, or something. Luskin’s post is entitled Tiktaalik Blown "Out of the Water" by Earlier Tetrapod Fossil Footprints, which should give you an idea. Briefly, the transitional (between fish and tetrapod) fossil Tiktaalik was found in rocks 375 million years old, but these new tetrapod fossils are 395 million years old, so this newly discovered tetrapod wasn’t a descendant of Tiktaalik. Luskin claims this means Tiktaalik isn’t a transitional form, even though it clearly has features of both fish and tetrapods (more on that below).Here’s Luskin:
The fossil tetrapod footprints indicate Tiktaalik came over 10 million years after the existence of the first known true tetrapod. Tiktaalik, of course, is not a tetrapod but a fish, and these footprints make it very difficult to presently argue that Tiktaalik is a transitional link between fish and tetrapods. It’s not a “snapshot of fish evolving into land animals,” because if this transition ever took place it seems to have occurred millions of years before Tiktaalik. [My bold.]
Of course, Luskin’s reasoning is wrong – if Tiktaalik is an intermediate between fish and tetrapods, then the discovery that this evolution also occurred earlier doesn’t suddenly magically mean that Tiktaalik isn’t an intermediate between fish and tetrapods anymore. The evidence that Tiktaalik is an intermediate is still evidence that Tiktaalik is an intermediate. Luskin doesn’t understand what an “intermediate” is – he thinks it has to be something on a direct line from (in this case) fish to existing land animals; it’s actually just a fossil that shows evolutionary change within lineages. (It has features of both a fish and a tetrapod, so it shows evolution happening.) Luskin thinks evolutionary theory says this happened only once. But evolutionary theory doesn’t say that. Transitional forms don’t have to be direct descendants of living species, they just have to be transitional between species (“cousins” of our ancestors, if you like) – that is, they just need to demonstrate evolution occurring.
PZ has a good post up, Casey Luskin embarrasses himself again, where he explains that Tiktaalik's status as a transitional form does not depend on us slotting it in a specific chronological time period as a link between two stages in the evolution of a lineage.
Why ID Is Useless
An interesting thing about Tiktaalik, is how Neil Shubin (its discover) managed to find it using a prediction of evolutionary theory. In his post, Luskin quotes Shubin. I’ll repost what Luskin quoted, but I’ll add a piece that he missed, from Zimmer and Shubin on Tiktaalik:
What evolution enables us to do is to make specific predictions about what we should find in the fossil record. The prediction in this case is clear-cut. That is, if we go to rocks of the right age, and the rocks of the right type, we should find transitions between two great forms of life, between fish and amphibian.
[…]
What we see when we look at the fossil record, at rocks of just the right age, is a creature like Tiktaalik. Just like a fish, it has scales on its back, and fins. You can see the fin webbing here. Yet when we look at the head, you see something very different. You see a very amphibian-like thing, with a flat head, with eyes on top. It gets even better when we take the fin apart. When we look inside the fin, as in this cast here, what you’ll see is bones that compare to our shoulder, elbow, even parts of the wrist—bone for bone. So you have a fish, at just the right time in the history of life, that has characteristics of amphibians and primitive fish. It’s a mix.
[My bold to indicate the bit that Luskin didn’t quote.]
Tiktaalik is undoubtedly transitional. With gills, scales and fins it is a fish, but its fins, instead of having the many tiny bones normally found in fish, had fewer but sturdier bones in its limbs – bones similar in number and position to those of every land creature that came later. Also, it had a flat head with eyes on the top like a modern amphibian, and it had a neck (which fish don’t have). It also had spiracles (breathing holes) on the top of its head, which suggests it had primitive lungs, and it had stronger ribs that allowed it to pump air into these lungs. Normal fish don’t need these because they breathe through their gills.
Luskin misses the point of all this with his “Tiktaalik, of course, is not a tetrapod but a fish” comment. Typical creationist – scientist finds a transitional form (fish to tetrapod) and creationist insists it’s not transitional because it’s still either a fish or a tetrapod. (Fish, in this case.) Nothing would satisfy Luskin – regardless of what new fossils are found, according to Luskin they’ll either be a fish or a tetrapod but never a transitional.
Also, it is beyond question that Shubin used evolutionary theory to predict where he would find Tiktaalik. He reasoned that if there were lobe finned fish but no terrestrial vertebrates 390 million years ago, and terrestrial vertebrates 360 million years ago, evolutionary theory would predict that you would find fossils of the transitional form in rocks around 375 million old (ie in between the two). And you would find them in a freshwater area, since both lobe finned fish and early amphibians lived in freshwater. So that’s where he looked. And guess what? That’s exactly where he found it. So evolutionary theory predicted where the fossil would be found. Again, this all flies right over Luskin’s head:
The New York Times presaged Shubin's argument, first reporting on Tiktaalik that "the scientists concluded that Tiktaalik was an intermediate between the fishes Eusthenopteron and Panderichthys, which lived 385 million years ago, and early tetrapods. The known early tetrapods are Acanthostega and Ichthyostega, about 365 million years ago." But would neo-Darwinism have predicted true tetrapods from 397 million years ago? Definitely not
No, but then neither would Intelligent Design (ID) have predicted this. The same way that ID didn’t predict Tiktaalik. These new fossils were discovered by real scientist doing real science, not by creationists using “Intelligent Design.” What this demonstrates is that science expands our knowledge while ID is completely vacuous and useless. ID didn’t predict anything (neither Tiktaalik nor these new fossils) since ID is nothing but a bunch of ignorant whining about evolution.
Where do we go from here? Well, clearly the creationists at the Disco-Tute will continue to miss the point entirely and claim that this discovery by real scientists somehow invalidates discoveries made by other real scientists. Meanwhile, actual real scientists will use this new information as a springboard to investigate and learn more. Philippe Janvier from the Museum National d'Histoire Naturelle in Paris (reviewer of the paper on the newly found fossil) told CNN:
"The divergence between the tetrapods and their closest fish relatives is much younger than previously thought and it obliges us to find actual evidence -- skeletons or complete fossils -- in much earlier strata that could enlighten us between this divergence."
Real scientists will now do actual research on these new fossils so we can learn more about our past. The difference between this and creationist poseurs such as Luskin, couldn’t be clearer.
Additional Reading
Jerry Coyne’s excellent book Why Evolution Is True has more on Tiktaalik and on transitional forms in general.