The Skeptic's Guide to the Universe
Skepticast #37: April 6th 2006 (Download MP3)
Topics:
Issue #1. News Items – fish evolution, prayer in medicine
Issue #2. E-mail – Noah’s ark, EVP, more on the solar eclipses
Issue #3. Science or Fiction
Issue #1. News Items
News Item #1 – Fish evolving to land animals -Discovered: the missing link that solves a mystery of evolution
Alok Jha, science correspondent
Thursday April 6, 2006
The Guardian
Scientists have made one of the most important fossil finds in history: a missing link between fish and land animals, showing how creatures first walked out of the water and on to dry land more than 375m years ago.
Palaeontologists have said that the find, a crocodile-like animal called the Tiktaalik roseae and described today in the journal Nature, could become an icon of evolution in action - like Archaeopteryx, the famous fossil that bridged the gap between reptiles and birds.
As such, it will be a blow to proponents of intelligent design, who claim that the many gaps in the fossil record show evidence of some higher power.
Richard Dawkins, the evolutionary biologist, said: "Our emergence on to the land is one of the more significant rites of passage in our evolutionary history, and Tiktaalik is an important link in the story."
Tiktaalik - the name means "a large, shallow-water fish" in the Inuit language Inuktikuk - shows that the evolution of animals from living in water to living on land happened gradually, with fish first living in shallow water.
The animal lived in the Devonian era lasting from 417m to 354m years ago, and had a skull, neck, and ribs similar to early limbed animals (known as tetrapods), as well as a more primitive jaw, fins, and scales akin to fish.
The scientists who discovered it say the animal was a predator with sharp teeth, a crocodile-like head, and a body that grew up to 2.75 metres (9ft) long.
"It's very important for a number of reasons, one of which is simply the fact that it's so well-preserved and complete," said Jennifer Clack, a paleontologist at Cambridge University and author of an accompanying article in Nature.
Scientists have previously been able to trace the transition of fish into limbed animals only crudely over the millions of years they anticipate the process took place. They suspected that an animal which bridged the gap between fish and land-based tetrapods must have existed - but, until now, there had been scant evidence of one.
"Tiktaalik blurs the boundary between fish and land-living animal both in terms of its anatomy and its way of life," said Neil Shubin, a biologist at the University of Chicago, and a leader of the expedition which found Tiktaalik.
The near-pristine fossil was found on Ellesmere Island, Canada, which is 600 miles from the north pole in the Arctic Circle.
Scientists from the Academy of Natural Sciences in Philadelphia, the University of Chicago, and Harvard University led several expeditions into the inhospitable icy desert to search for the fossils.
The find is the first complete evidence of an animal that was on the verge of the transition from water to land. "The find is a dream come true," said Ted Daeschler of the Academy of Natural Sciences.
"We knew that the rocks on Ellesmere Island offered a glimpse into the right time period and were formed in the right kinds of environments to provide the potential for finding fossils documenting this important evolutionary transition."
When Tiktaalik lived, the Canadian Arctic region was part of a land mass which straddled the equator. Like the Amazon basin today, it had a subtropical climate and the animal lived in small streams. The skeleton indicates that it could support its body under the force of gravity.
Farish Jenkins, an evolutionary biologist at Harvard University said: "This represents a critical early phase in the evolution of all limbed animals, including humans - albeit a very ancient step." Tiktaalik also gives biologists a new understanding of how fins turned into limbs. Its fin contains bones that compare to the upper arm, forearm and primitive parts of the hand of land-living animals.
"Most of the major joints of the fin are functional in this fish," Professor Shubin said.
"The shoulder, elbow and even parts of the wrist are already there and working in ways similar to the earliest land-living animals."
Dr Clack said that, judging from the fossil, the first evolutionary transition from sea to land probably involved learning how to breathe air. "Tiktaalik has lost a series of bones that, in fishes, covers the gill region and helps to operate the gill-breathing mechanism," she said. "The air-breathing mechanism it had would have been elaborated and having lost the series of bones that lies between the head and the shoulder girdle means it's got a neck, it can raise its head more easily in order to gulp the air.
"The flexible robust limbs appear to be connected with pushing the head out of the water to breathe the air."
H Richard Lane, director of sedimentary geology and palaeobiology at the US National Science Foundation, said: "These exciting discoveries are providing fossil Rosetta stones for a deeper understanding of this evolutionary milestone - fish to land-roaming tetrapods."
A cast of the fossil goes on display at the Science Museum in South Kensington central London today.
News Item #2 – Study: Praying Won't Affect Heart Patients
By MALCOLM RITTER, AP Science Writer
Thu Mar 30, 8:03
NEW YORK - Does praying for a sick person's recovery do any good? In the largest scientific test of its kind, heart surgery patients showed no benefit when strangers prayed for their recovery.
And patients who knew they were being prayed for had a slightly higher rate of complications. The researchers could only guess why.
Several scientists questioned the concept of the study. Science "is not designed to study the supernatural," said Dr. Harold G. Koenig, director of the Center for Spirituality, Theology and Health at the Duke University Medical Center.
The researchers who tested the power of prayer emphasized that their $2.4 million study could not address whether God exists or answers prayers made on another's behalf. The study could look only for effects from the specific prayers offered as part of the research, they said.
The highly anticipated study "did not move us forward or backward" in understanding the effects of prayer, said Dr. Charles Bethea, a co-author and cardiologist at the Integris Baptist Medical Center in Oklahoma City. "Intercessory prayer under our restricted format had a neutral effect."
Dr. Herbert Benson of Harvard Medical School, co-principal investigator of the study, agreed. "We cannot come to a conclusion, except to say that by this study design, with its limitations, this is what we found."
The researchers also said they didn't know why patients who knew they were being prayed for had a higher rate of complications than patients who only knew that such prayers were a possibility.
Maybe they became anxious by the knowledge that they'd been selected for prayers, Bethea said: "Did the patients think, 'I am so sick that they had to call in the prayer team?'"
The researchers said family and friends shouldn't be discouraged from telling a patient about their plans to pray for a good recovery.
Experts called it the largest and best-designed study ever to test the medical effects of intercessory prayers _ praying on behalf of someone else. That's different from studying the effect of a person's prayers and spiritual practices on his or her own health; many studies of that have shown a positive effect.
The new study followed about 1,800 patients at six medical centers. It was financed by the Templeton Foundation, which supports research into science and religion, and one of the participating hospitals. It will appear in Tuesday's issue of the American Heart Journal.
The research team tested the effect of having three Christian groups pray for particular patients, starting the night before surgery and continuing for two weeks. The volunteers prayed for "a successful surgery with a quick, healthy recovery and no complications" for specific patients _ their identities known only by first name and first initial of the last name.
The patients, meanwhile, were split into three groups of about 600 apiece: those who knew they were being prayed for, those who were prayed for but only knew it was a possibility, and those who weren't prayed for but were told it was a possibility.
The researchers didn't ask patients or their families and friends to alter any plans they had for prayer, saying such a step would have been unethical and impractical.
The study looked for any complications within 30 days of the surgery. Results showed no effect of prayer on complication-free recovery. But among patients who did receive prayers, 59 percent of the patients who knew they were being prayed for developed a complication, versus 52 percent of those who were told it was just a possibility.
Paul Kurtz, professor emeritus of philosophy at the State University of New York at Buffalo, and chairman of the Committee for the Scientific Investigation of Claims of the Paranormal, had a blunt response when asked why he thought the study found no effect of prayer.
"Because there is none," he said. "That would be one answer."
He added that while he tries to keep an open mind, he's seen no good evidence for such an effect in past studies. The new work, he said, "gives added emphasis to those who have been skeptical."
Koenig, of Duke University Medical Center, who didn't take part in the study, said the results didn't surprise him.
"There are no scientific grounds to expect a result and there are no real theological grounds to expect a result either," he said. "There is no god in either the Christian, Jewish or Muslim scriptures that can be constrained to the point that they can be predicted."
Within the Christian tradition, God would be expected to be concerned with a person's eternal salvation, he said, and "why would God change his plans for a particular person just because they're in a research study?"
Dr. David Stevens, executive director of the Christian Medical and Dental Associations, said he believes intercessory prayer can influence medical outcomes, but that science is not equipped to explore it.
"Do we control God through prayer? Theologians would say absolutely not. God decides sometimes to intervene, and sometimes not," he said.
As for the new study, he said, "I don't think ... it's going to stop people praying for the sick."
Copyright 2006 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
Issue #2. E-mail
E-mail #1 – Noah’s Ark
Hi guys,
I love your show! I've listened to every one by now (though I'm a week behind).
I have a couple thoughts about the Noah's ark segment from 3/22. I couldn't verify the comment about two of each predator and seven of the rest although I did find references to seven of the clean and two of the unclean. I suppose that's it?
Also would any of you would care to hypothesize just how big a ark would have to be to house two of each species today? How much food would they have to carry for the duration? How much is the minimal amount of space they would need, etc.? It would be an interesting thought experiment. Also any insight into the geleolocigal evidence that we would expect to find for a mass extinction of that size? I'd be interested to hear some off the cuff remarks (not a detailed analysis), or if you know of some online resource that already does this, I'd be grateful if you could point it out.
Thanks,
-Keith Bentrup
http://www.talkorigins.org/faqs/woodmorappe-review.html
http://skepdic.com/noahsark.html
E-mail #2 – EVP
I just saw this awful movie called "White Noise". It is about a man who records EVP's (Electronic Voice Phenomena) to communicate with his dead wife and of course lets the bad ghosts get through. Cliché, poorly acted and boring, yes, but I really got angry when there was a disclaimer at the end of the film which said that of the _____ EVP's recorded each year, 1 out of 12 is overtly threatening. This film was taking itself seriously!!! When I did some research on the internet, I found that there is a whole society dedicated to "recording" EVP's and even a website where you can buy special recording devices and receive helpful advice about the best way to pick up an EVP. Help!!! I would love to hear what you guys think about this.
Shewells
E-mail #3 – Follow up on Solar Eclipses
I was somewhat surprised to hear your assertion that even during totality, a solar eclipse is not safe to look at because "a crescent of the sun is still visible" or something along those lines, and that "most people now know it's not safe to look at an eclipse." I'm not an astronomer, but I'm pretty sure this is incorrect. During totality, the entire photosphere (the bright "surface" of the sun) is blocked by the moon. Thus the term "totality." At this time, it is in fact safe to look. Every reference I could find on the NASA Eclipse website seems to confirm this. I'd be interested to hear your source for the opposite position.
Brian Millsap
E-mail #4 – Frank the Skeptic
Steve Novella, and the rest of the podcast panel,
I discovered your podcasts a couple of months ago, and have listened to most of them. Thanks for the great shows, they are fabulous!
What happened to Jan Helen Mgee, the psychic detective who claimed 100% accuracy and agreed to be tested? Was there a follow-up on that? I've noticed that you guys seem to be in agreement on most issues most of the time. It would be fun if you had more "skeptics of the skeptics" on. For example how about a Scientologist? Have you heard of Heber Jentzsh? I think he would be an awesome guest for the show. I've seen him in some 'debates' on xenu.tv, and you guys would really have your work cut out for you with him!
In the meantime, I'll propose some tidbits to stimulate debate amongst yourselves, and give you a chance to flex your big brains.
1) The law of conservation of energy and matter says that energy and matter cannot be created nor destroyed, but only changes form. Scientists believe the Universe began with a 'Big Bang', which is essentially a theory that states that the Universe exploded outward from an infinitesimally small point at a specific point in history. If you assume that the Universe is not oscillating, (a point on which most cosmologists are now in agreemment), then you must conclude that the Universe was created out of nothing fourteen billion years ago. Therefore, current scientific theory is an 'inconsistent belief set'.
2) Can experts tell, with 100% accuracy, if a photo has been digitally altered? Can they tell with 100% accuracy if a photo has been doctored in any way? Everyone thinks they can spot a toupee, but it's only the bad ones they spot, the good ones aren't even noticed. Could you use this argument here?
3) Could the placebo effect be evidence of a mind/ body connection? From my understanding, a new drug need only to be proven slightly better than the placebo for it to be deemed useful. Given the proven and real effects of the placebo for a wide range of health problems, why don't doctors prescribe them? If new-agers call it spontaneous healing, the power of positive thinking or whatever, and skeptics call it the placebo
effect, isn't it just a difference of labeling?
That's all for now. Keep up the good work!
Frank the Skeptic
Newfoundland Canada
Issue #3. Science or Fiction
Each week our host will come up with three science news items or facts, two genuine, one fictitious. He will challenge our panel of skeptics to sniff out the fake – and you can play along.
Theme for this week: This week, host Steven Novella is reporting from the American Academy of Neurology annual meeting in San Diego, CA. The science or fiction items are draws from papers presented at this meeting.
Item#1: Effects of Auditory Stimulation with Popular Music on Visuomotor integration, rapid alternating movement, and gait in Parkinson’s disease. (bottom line – listening to pop music improves motor function in Parkinson’s disease)
Item #2: Does a Birthday predispose to stroke, transient ischemic attack, and myocardial infarction. (bottom line – people are more likely to have strokes and heart attacks on their birthday – increased risk by 27%)
Item #3: Efficacy of environmental color manipulation on the reduction of seizure frequency in primary generalized epilepsy (bottom line – people living in an environment colored toward the blue end of the color spectrum have fewer seizures than those living in an environment colored toward the red end of the spectrum.)
Answer:
Item #1: Science
Item #2: Science
Item #3: Fiction