Archive for August, 2010

Aug 13 2010

Lucy in the Cave with Tools

Published by under General Science

In paleontology it can only be estimated how long a species lived or a phenomenon existed. The beginning of a species’ tenure on this earth is marked by the oldest specimen that we have of it, and the end by the youngest specimen. But given that the fossil record is spotty, chances are that the oldest specimen is not from the very beginning, and the youngest right from the very end. So the temporal range of an extinct species is certainly at least a bit longer than our current fossil specimens would indicate.

This situation also means that on a regular basis the time range of species and events will be modified by new finds. We are constantly expanding and modifying our reconstruction of the past in this manner.

But still it is always exciting to learn that something interesting is much more ancient than we previously believed – such as human toolmaking. A recent find provides smoking-gun evidence that our ancestors were making stone tools about 1 million years earlier than indicated by previous evidence.

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5 responses so far

Aug 12 2010

Alleged Psychic Finds Fish

Published by under Paranormal,Skepticism

Self-proclaimed psychic Crystal Newage (rhymes with “sewage”) claims that she was psychically led to find a large trout in a lake near her home.

She was fishing with some friends and claims that her spirit guide told her where to fish, and which lure to use. After about an hour with her line in the water she pulled up a 3 pound rainbow trout. She is quoted as saying:

You can call it luck, but what are the chances that I would have caught this particular trout right where my spirit guide told me to look. I could sense that there was something special about this location – it has a clear energy.

“We were fishing for bass,” her friend recalls, “but I guess trout was in our destiny that day.”

Skeptics argue that Crystal’s experience is not evidence of genuine psychic ability, but for those who believe it is all the evidence they need.

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7 responses so far

Aug 11 2010

Wacky Medical Treatments

Published by under Skepticism

Check out this photo gallery of strange medical treatments (the title says “unorthodox cures” which is begging the question – do they cure anything). Seeing a photo of a treatment being given has more impact than just reading a description.

My favorite is the woman with smoking sticks jammed in her ears. This is a form of moxibustion, often mixed with acupuncture. I couldn’t find an explanation for the walnut in the eye.

I have covered bee venom therapy before.

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20 responses so far

Aug 10 2010

Regenerating Spinal Cords

Published by under Neuroscience

This post is not about a “breakthrough” in spinal cord regeneration. It is about a baby-step. But it is a notable baby-step. A colleague of mine who does spinal cord research noted years ago that over the next few decades, if we succeed in fixing spinal cord injury, it will not be through any big breakthrough. It will be through a hundred baby-steps. We should celebrate each one, but keep them in context. Mainstream media’s obsession with “breakthroughs” simultaneously oversells and diminishes the real value of these advances.

So here it is – published online in Nature Neuroscience is a study in mice in which researchers have documented meaningful regeneration of neurons distal to a spinal cord injury. They did this by deleting a gene that downregulates another genes that promotes neuronal regeneration. Here’s the background:

The broad concept here is that biological systems have evolved mechanisms to inhibit cell growth and proliferation. As cells mature and differentiate they generally lose their ability to proliferate (most tissues contain stem cells to produce new cells). This inhibition is critical – without it cancers would run rampant. But this inhibition also limits healing and regeneration (a necessary evolutionary trade-off).

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7 responses so far

Aug 09 2010

The Bananas Hubbub

Published by under General Science

I love bananas. They are probably the most common fruit that I eat. Which is partly why I was intrigued when I learned that the cultivar of banana that I have known my entire life, the Cavendish, is an inferior variety to the banana that became popular in the first half of the 20th century, the Gros Michel.

This is a story of cultivation, economics, infection, and genetic engineering – with a promising update at the end. But let’s start with a little history.

The banana, despite the claims of “banana man” Ray Comfort, is a highly cultivated fruit. Evolved varieties are hard, contain large seeds, and are not very sweet. Cultivation resulted in the bananas we know and love – sweet, seedless, and creamy. Because they are seedless, they have to be propagated asexually through offshoots. This means that every Cavendish banana is a clone of every other one.

Photo by Timothy Pilgrim

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Aug 05 2010

Proximal Intercessory Prayer

One of the core “pearls” of this blog is that not all scientific studies are created equal. It is common for the media and the public to cite the fact that “a study shows” some claim or other, but such appeals to evidence are worthless unless we can assess the quality of the study. We now have a gaggle of science bloggers – real scientists blogging about research – to help explain all the various ways to look at the quality of a study, and hopefully this is resulting in a more savvy population of science enthusiasts (the kind of people who read science blogs).

Let’s take the following hypothetical study: The study included 24 subjects who were all treated openly with the intervention in question. There was no blinding or control group – so everyone in the study, subjects and experimenters, knew that every subject was getting the treatment. The treatment involves active physical intervention with the subject. The protocol also calls for multiple interventions if initial treatments are not effective – essentially the subjects receive repeat treatments as long as possible until they report a response.

The outcome was either a change in vision or hearing. Subjects reported impaired vision or hearing at the beginning of the study and were tested with standard vision or audiology tests before and after treatment. All subjects demonstrated improvement from the intervention.

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31 responses so far

Aug 04 2010

Some Follow up on CCSVI

Earlier I wrote about two new studies that cast doubt on the concept that Multiple Sclerosis (MS) is caused by chronic venous insufficiency (CCSVI). I also speculated that if the research ultimately shows that CCSVI is a dead end, either it will fade into a footnote on medical history, or it will continue on the fringes as pseudoscience. If the comments are any indication, it seems that the latter seems more likely.

Several commenters objected to my treatment of CCSVI. None of them, I would point out, had anything substantive to say about the two studies I reviewed. These studies looked at whether or not there is a difference between subjects with MS and normal controls in terms of their cerebral venous anatomy and function, and both found no difference at all. This was a very important replication of the research of Dr. Zamboni that found a dramatic difference. When two independent researchers fail to replicate a finding like this, that seriously calls into question the original claims.

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46 responses so far

Aug 03 2010

Vegatest – High Tech Pseudoscience

John (a fictitious patient) is suffering from fatigue, poor sleep, difficulty concentrating, and has been noticing little bumps on his skin. His primary care doctor performed a basic workup, which was completely negative, and started asking John about his stress levels and sleep habits. But John was convinced that something was happening to him and so sought additional opinions.

He was referred to Dr. Charles Rank, an allergist, by a work colleague. Dr. Rank took a typical medical history but then also asked John extensively about his environmental exposures and his diet. Dr. Rank believed that John’s history was suggestive of an allergy, and so he brought out his newly acquired Vega II diagnostic testing machine.

The Vega II is a sophisticated-looking piece of electronic equipment, and Dr. Rank seemed confident in working its many knobs and buttons. He attached a few electrodes to John and then pressed a metal probe against his skin while John held in turn a series of glass tubes, each filled with a different substance. Each time the Vega II squealed and beeped, and John could see a gauge registering to varying degrees. It all looked quite complex and impressive.

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5 responses so far

Aug 02 2010

CCSVI – The Importance of Replication

Published by under Neuroscience

Scientists and skeptics are familiar with this pattern – a preliminary study suggests a wildly new understanding of a scientific or medical question. The scientific community is cautiously skeptical but interested. The press proclaims a stunning breakthrough, and the public is briefly fascinated. If the new discovery concerns a medical treatment, the community of those affected become fixated on the potential new “cure”, and many start demanding treatment based solely on the preliminary evidence. But then the wheels of research begin to grind and, more often than not (because that is the nature of discovery) the new idea turns out to be wrong – it fails the critical step of replication.

Then one of two things will happen: either the new idea or treatment will fade, becoming little more than a footnote in the history of science, or a subculture will persist in believing in the treatment and will dismiss contrary evidence and mainstream rejection as a conspiracy. Which course the new idea will take seems to depend largely on the original scientist – if they accept the new evidence and abandon their claims, it will likely fade. If they refuse to give up in the face of new evidence, then a new pseudoscience will likely be born.

We have seen this pattern play out with Laetrile, psychomotor patterning, cold fusion, and many other ideas.

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32 responses so far

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