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First the link to this week’s complete list as HTML and as PDF.
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If you believe Kolbabová et al., the diurnal melatonin cycle of calves is upset by the magnetic field from 50 Hz power lines at least in winter. Is it?
Their n=80 and n=20/20 in Figs 1--3 violates common standards, as it does not count the number of subjects as usual but that of individual measurements. The total size of their eight groups, summer-winter, male-female, and field-no field was two calves each.
Like psychologists often do, they show the standard errors. The SE is appropriate for one value imprecisely measured many times, but not, as in this case, for many separate values with a genuine inherent scatter, each one measured precisely. For that the standard deviation alone is relevant and that is nine times the length of the error bars shown in figs 1--2 and 4.5 times that of figure 3. So their effect, even if real, is totally lost in the natural variability.
The wide range of that scatter is shown in figure 4. Contrary to their regression I can see no trend here whatever, but rather two distinct groups with less than and over 30 days of age. Reading their methods and that the stabling and experiment began at 31 days of age this looks plausible.
Looking closely at figure 6b it seems the groups are systematically ordered relative to the front of the building. They will have received systematically different levels of light and audible transformer hum. Humans and food will have come to them in an invariant order and so will the taking of samples at two in the morning.
This ordered arrangement may well explain why the male-female difference was far greater than either the summer-winter or the field-no field one. You don’t normally expect large hormonal differences in immature animals.
In all it’s another completely meaningless non-result reminding us of the hoaxes sometimes played on journal editors. A good friend of mine picked it up, because it had already found its way into the sensationalist yellow press.
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In a way, Lee Berger is the first to introduce science into anthropology. If one set of fossils, essentially one complete species, can only be examined by a single set of investigators, where does that leave the principle of reproducibility?
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When wood mice are brought into a symmetrically circular and totally featureless environment, they show a slight tendency to build their nests toward the magnetic north or south. According to Malkemper et al. this slight tendency is upset by magnetic fields in the Mhz range. So yes, small mammals do have a weak magnetic sense but it’s hardly relevant for their lives.
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Let’s see what Rickford et al. are actually saying. Only about half the families offered vouchers actually chose to move into lower poverty areas. The change in language use by children was highly dependent on their parents’ motivation and effectively only occurred, where parents cared and actively wanted to get away from drugs and toward better schools. In those cases the move constituted a large change in circumstances with many effects, the changes in language use and earning prospects being two of them. Assuming a causal effect from language to earnings based on that sample and on that result looks utterly ridiculous to me. Quite apart from that, a 3 % change in life time earnings is meaningless and totally lost in the noise.
The far more interesting question would be to look at those, where the large and highly artificial intervention did not result in any measurable change. Obviously for those where it worked the process was speeded up but they were already on the path to advancement. They add nothing to the question what it is holding the others back and what can be done for them and their children. Personally I see Laura Bush’s (she of the unfortunate husband) library initiative to be more promising.
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I have always liked the idea of the Basques and perhaps the Sami as pre-Neolithic remnants of the original Upper Paleolithic Europeans. Like so many other nice ideas Günther et al. have now shown it to be wrong.
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