Letters to the Editors; July 2003; Scientific American Magazine; by Staff Editor; 2 Page(s)

The March issue generated varying amounts of heat. The relative wisdom of mining data from credit cards and other purchasing patterns to sniff out terrorists, in "Total Information Overload" [Perspectives], sparked some ire. But perhaps the hottest topic--literally--was "Dismantling Nuclear Reactors," and the related, contentiously debated idea of whether to store high-level radioactive waste at Yucca Mountain ["Man against a Mountain," Profile, by Steve Nadis]. The opposing sides--for and against Yucca as a permanent facility--are both wrong, argues Gregory L. Schaffer of Cupertino, Calif.: "All we really need to do is guarantee that Yucca Mountain is stable for, say, 500 or 1,000 years. If problems occur in a century or two, the technology of that era should easily solve them." Searing commentary on these and other articles in the March issue appears on the following pages.

In "Which Came First, the Feather or the Bird?" Richard O. Prum and Alan H. Brush say that fossils in China dated from 124 million to 128 million years ago help to explain how feathers developed. Earlier in the article, however, the ancient bird Archaeopteryx is dated from 148 million years ago.