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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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