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November 2004

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News Scan Briefs; November 2004; by JR Minkel, Charles Choi; 2 page(s)

Workers in some species of social insects police one another to prevent individuals from laying their own eggs, as opposed to helping rear the queen's. Researchers assumed that policing is selected for in colonies that contain multiple queens or mates, which means that workers share more genes on average with a queen's offspring than with one another's and so have an incentive to force others to invest in the queen's young. But a survey of research on 50 species of ants, bees and wasps finds that once-mated single queen colonies are just as likely to crack down on cheaters as those with multiple queens or mates. The surveyors, Robert Hammond and Laurent Keller of the University of Lausanne in Switzerland, point out that policing should also arise if unchecked cheating imposes significant costs on the hive, such as workers loafing. The drive for efficiency thus seems to outweigh relatedness in leading to actual policing, Hammond says. The work appears online in the September Public Library of Science Biology.

Instead of phoning home, E.T. might be better off writing. Searching for extraterrestrial intelligence typically means exploring the sky for radio messages, but such waves grow weaker as they cross space. Beaming more than a basic note across the stars requires an antenna the size of Earth, calculate electrical engineer Christopher Rose of Rutgers University and physicist Gregory Wright of Antiope Associates in Fair Haven, N.J. On the other hand, they calculate roughly 10 billion billion nanosize bits of data--all Earth's current written and electronic information--could be inscribed via scanning tunneling microscopy within a gram of matter. Interstellar mail could therefore prove far more efficient over long distances, though much slower. In the September 2 Nature, Rose and Wright suggest that resting points for parcels could lie in orbits near the Earth, moon, asteroid belt and sun or on surfaces in the inner solar system.

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