Letters

A Boy Scout’s salute
I am a Boy Scout doing the Communications Merit Badge. I am supposed to write to the editor of a magazine and express my opinion.

I’ve always loved the Atom & Cosmos section because I’m very interested in particle physics and on the other end of the scale, cosmology. “Earth-y orb found in habitable zone” (SN: 3/10/12, p. 14) describes a planet 22 light-years away from Earth that could potentially have life on it. It really is fascinating to think that there are other civilizations out there in space all searching for other forms of life.

Another topic that I love reading about is black holes. Being someone who knows the tip of the iceberg about things like black holes, it’s really mind-boggling to read the works and findings of brilliant scientists in such a comprehensible way. Schools don’t teach this sort of material, and these science topics are what I love to learn about. It really is a blessing to be captivated by almost any article in Science News.
Matthew Kotila, San José, Calif.

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Which came first, lung or bladder
In “African lungfish walk in water” (SN: 1/14/12, p. 12), the author comments that primitive lungs “probably evolved from the air bladders found in fish.” Since it might very well be just the opposite, instead of this phrasing I think it better to simply acknowledge the evolutionary homology [relatedness] of air bladders and lungs. The air bladders seen in modern ray-finned fishes are very different in their anatomical details from lungs. It is plausible that the “lung” (or lungs, depending on species) of modern lungfishes — virtually identical morphologically to the lungs of tetrapods — represents the ancestral (or primitive) condition seen in some of the now-extinct “transitional” fishes alluded to in the article.
Kevin Lumney, Sunbury, Ohio

The reader makes a good point. It is possible that lungs and swim bladders evolved separately. As evolutionary biologist Neil Shubin of the University of Chicago says, these kinds of structures arise “via similar processes, but it is unclear whether one is derived from the other.” — Editors

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Correction
An entry in the 90th anniversary issue of Science News (SN: 3/24/12, p. 25) incorrectly stated that atomic timekeeping was reported in 1947. The entry should have said that the U.S. National Bureau of Standards reported quartz timekeeping accurate to a millionth of a second in 1947. The first atomic clock was actually reported in 1949, also by that agency (“Atoms control new clock,” SN: 1/15/49, p. 35).