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Waking Up to the Dawn of
Vertebrates
Discovery of the earliest fossil fish pushes back the origin of
vertebrates to the Cambrian explosion.
Vacuum tubes’ new image: Too
small to see
Experimental versions of vacuum tubes now rival minuscule semiconductor
devices in size and are expected to outperform those devices under intense
radiation and at high temperatures.
Genetic variants may ease leukemia risk
Having variations in a gene for an enzyme that modifies folic acid—a
vitamin critical to DNA synthesis and repair—may help some people ward
off acute lymphocytic leukemia.
Each nostril smells the world differently
One nostril lets in air faster than the other—they take turns throughout
the day—and this affects sensitivity to odors.
Enzyme offers promise of Alzheimer’s
drugs
Scientists have finally identified an enzyme that may help cause Alzheimer’s
disease.
Y2K problem looms in Hubble repair
If a shuttle mission to repair the Hubble Space Telescope doesn’t go up
as planned in December, it could face a Y2K computer problem.
Chimps outdo people in genetic diversity
The low variation along a particular stretch of DNA in humans compared
with chimps has implications for how both groups evolved.
Soy slows growth of prostate cancers
Animal studies now suggest that soy cuts the growth and severity of
prostate cancers by inducing suicide in the cancer cells.
The Whale’s Tale
Searching for the landlubbing ancestors of marine mammals
Biologists clash over how to draw the whale family tree.
A Controversial Shot in the Arm
Possible AIDS vaccine taps an unlikely protein called Tat
Debate over the roles of an HIV protein previously recognized as helping
the virus turn on its genes hasn’t stopped scientists from using it in
experimental vaccinations against AIDS.
Astronomy
Another planet for the solar system?
Two studies hint—but by no means prove—that the solar system might
harbor a 10th planet, far beyond Pluto in a reservoir of comets known as
the Oort cloud.
Moon crash comes up dry
The myriad observations of the moon immediately after the Lunar Prospector
spacecraft deliberately crashed into it on July 31 have shown no evidence
of water.
Behavior
When monkeys play dumb
Low-ranking rhesus monkeys do poorly on a learning task only if they see
dominant monkeys hanging around.
The politics of scale
Small differences in a poll’s rating scale—0 to 10 for honesty
compared with –5 to +5, for example—influence how much people report
liking a politician as well as their ensuing opinion of that politician.
Biology
Does March Madness need a
time-out?
Basketball teams that have to travel across three time zones to play face
twice the risk of being upset in the first round of NCAA tournaments.
A lead on why lead hurts the brain
Lead competes with calcium to bind to certain molecules in nerve cells,
which may explain why the metal damages the nervous system.
Biomedicine
Supplement could fight cystic fibrosis
Mice carrying the genetic defect that causes cystic fibrosis in people
were fed large doses of the fatty acid docosahexaenoic acid (DHA) for a
week, and signs of the disease were reversed.
Clogged arteries block hormone effects
Atherosclerosis might block genes for estrogen receptors, perhaps
explaining why a large study of hormone-replacement therapy didn’t show
the expected benefit of estrogen against heart disease.
