Letters to the Editor

18961

I detect a blind spot in this article. Theorists were quick to offer explanations of why the fine-structure constant might have been different 12 billion years ago. But no one thought to question the chain of reasoning that led to that conclusion. We know that quasar spectra are drastically redshifted during their multibillion-year journey to […]

18969

If, as it appears from “Ill winds,” dust storms are so important, and if they can be tracked from space, it would seem as though the weather bureaus should give dust storm warnings, as they do for hurricanes, tornados, and thunderstorms. It might be difficult to get across to government bureaus that this is important, […]

18976

The story correlates red tides in Florida with Saharan dust storms. The cover story of the same issue (“Dust, the thermostat,” p. 200: Dust, the Thermostat) dealt, in part, with dust blowing across the Mediterranean Sea and the Atlantic Ocean. Are there “red tides” in these areas? Are they correlated with Saharan dust? David D. […]

18975

We read that the Chaco Anasazi builders used “large timbers” 5 meters long, 22 centimeters in diameter, and weighing 275 kilograms. As anyone who splits his own firewood could tell you, something is amiss here. The Handbook of Chemistry and Physics tells us that ponderosa pine has a density of about 0.5 gram per cubic […]

18974

Regarding “Constipation might signal Parkinson’s,” did anyone consider that the patients’ diet might be the reason for constipation and the Parkinson’s disease? Your article reads as if diet can’t affect constipation. Mark Bremer Benicia, Calif.The researchers accounted for smoking, coffee consumption, laxative use, jogging, and intake of fruits, vegetables, and grains. –N. Seppa

18968

I’ve just read your account of the “ekpyrotic model” of the universe. Although descriptive, “ekpyrotic” seems rather contrived and is hard to pronounce. Certainly it lacks the pizzazz of “Big Bang.” And “Big Crunch” has been used previously to refer to the “anti-Big Bang” catastrophe thought to be awaiting the universe. How about the “Big […]

18973

“Bt corn risk to monarchs is ‘negligible'” is full of manipulative words. How exactly was the “highly polarized atmosphere surrounding genetically modified crops . . . hampering attempts to rationally plan and evaluate research”? The companies that make the strains of corn discussed in the article are not named, of course. Nor are any ties […]

18967

Regarding “Neandertals show ancient signs of caring,” it seems to me that rather than “pounding, chopping, or cooking tougher food” for a friend or relative, these kindly Neandertals probably just masticated a mouthful before passing it on. This is something people do all over the world. Sharon Rudahl Los Angeles, Calif.

18972

Several key ideas seem missing from “Life on the edge”: 1) the fundamental nature of overpopulation and how it combines with technology to drive mass extinction; 2) the concept of functional extinction, an example being the decimated numbers and diminished range of elephants; and 3) a reasonable extrapolation of human technology. The statement that our […]

18966

One cannot be around cats long without observing that they have intelligence and personalities nearly as complex and diverse as people do. They communicate with each other and people, both verbally and with body language. They have preferences for whom they associate with, both human and feline, and those can change. I think that complexity […]

18965

The article says that evidence of past climate variations in Antarctica may invalidate global warming as a cause for the recent demise of several ice shelves in that area. Isn’t the length of time over which the changes occurred the critical thing? If the changes are occurring over roughly the same time span as they […]

18971

In the photograph of X-ray jets and point sources in the galaxy Centaurus A, shown in “Shocks jolt jet set galaxy, X rays reveal,” many of the point sources seem to be regularly spaced along arcs. The pattern is reminiscent of an X-ray diffraction pattern from a crystal (a microscopic event mirrored here on a […]