SCIENCE OBSERVER
In the News
This roundup summarizes some notable recent items about
scientific research, selected from news reports compiled in
Sigma Xi's free electronic newsletters Science in the News
Daily and Science in the News Weekly. Online: sitn.sigmaxi.org and www.americanscientist.org/sitnweekly
Planets Galore
Astronomers have found 16 candidate planets hidden deep within the
Galactic bulge, making them the most distant sampling of extrasolar
planets yet. Five of the candidates were deemed
"ultra-short-period planets," because they circle so close
to their parent stars that their orbital periods are less than a
day. These results indicate that the abundance of extrasolar planets
in the Galactic bulge is similar to that previously determined for
the solar neighborhood, suggesting that the Milky Way as a whole
must harbor a rich endowment of other worlds.
Sahu, K. C., et al. Transiting extrasolar planetary
candidates in the Galactic bulge. Nature 443:534-540
(October 5)
Element 118 Redux
Using a cyclotron to shoot calcium 48 at californium 249 and curium
245, nuclear physicists from the Joint Institute for Nuclear
Research in Dubna, Russian Federation, and from Lawrence Livermore
National Laboratory in California have managed to produce an element
with 118 protons in its nucleus. The naming of this new element and
its decay product with 116 protons in the nucleus is being postponed
until the results can be confirmed at other labs. Investigators from
California’s Lawrence Berkeley National Laboratory said they
produced element 118 in 1999, but retracted that claim three years
later when one of the people involved admitted to fabricating data.
If confirmed, the new discovery would support the existence of an
"island of stability," a group of theoretically stable
atoms with relatively high numbers of protons and neutrons.
Oganessian, Yu. Ts., et al.Synthesis of the isotopes of
elements 118 and 116 in the 249Cf and
245Cm + 48Ca fusion reactions.
Physical Review C74:044602 (October 9)
Veggies Slow Mental Decline
Investigators at Rush University Medical Center in Chicago mounted a
prospective study of nearly 4,000 people who were 65 or older to
test whether their consumption of fruits and vegetables might affect
their mental functioning. Follow-up examinations were performed
three and six years after baseline measurements were made. These
tests showed that eating vegetables was associated with a slower
rate of cognitive decline. The consumption of fruit did not,
however, appear to confer the same benefit.
Morris, M. C., et al.Associations of vegetable and
fruit consumption with age-related cognitive change.
Neurology 67:1370-1376 (October 24)
Bird-Brain Has a New Meaning
The largest known avian skull has been unearthed from Miocene-age
rocks of Patagonia, Argentina. The skull, which is bigger than the
head of a horse, belonged to a species of phorusrhacid or
"terror bird," flightless carnivores that probably fed on
sheep-sized rodents that populated the area some 15 million years
ago. The strangely slender lower leg bones of this massive bird,
which stood about 3 meters high, indicates that it may have been
swifter than was previously believed, a conclusion that brings into
question the commonly held view that body size is inversely
correlated with an animal’s agility.
Chiappe, L. M., and S. Bertelli. Skull morphology of giant
terror birds. Nature 443:929 (October 26)
Elephant, Know Thyself
Experiments at the Bronx Zoo have demonstrated that elephants are
able to recognize themselves in a mirror, suggesting that pachyderms
possess a higher level of self-awareness than was previously
suspected. Before this point, only great apes (including Homo
sapiens) and dolphins had been thought to have such abilities.
But the behavior of the elephants tested by placing real and sham
marks on the right sides of their heads showed that they were indeed
able to recognize that they were looking at themselves and not
another elephant when they gazed into a large mirror.
Plotnik, J. M., F. B. M. de Waal and D. Reiss. Self-recognition
in an Asian elephant. Proceedings of the National Academy
of Sciences of the U.S.A.103:17053-17057 (November 7)
Bee It That Old
The oldest known bee has been found preserved in a piece of
amber—fossilized tree sap—from Myanmar (Burma). The
species, Melittosphex burmensis, is estimated to have lived
about 100 million years ago. Previously known examples of fossil
bees are 35 to 45 million years younger. The new amber-bound
specimen measures just under 3 millimeters long, demonstrating that
at least some of the earliest bees were tiny, which is consistent
with the small size of some contemporary flowers. M.
burmensis shows some traits that are similar to those of wasps,
suggesting that the find may represent a transitional form.
Poinar, G. O., and B. N. Danforth. A fossil bee from Early
Cretaceous Burmese amber. Science 314:614 (October 27)
Cloak of Invisibility
Physicists and engineers have created a working model of an
"invisibility cloak" that lets microwave radiation pass
through it with minimal distortion. The device contains a set of
concentric circles that deflect electromagnetic plane waves
around a copper cylinder hidden inside while minimizing reflections
and shadows. The circles are fashioned of a
"metamaterial," being made up of an array of special
shapes cut from copper film. Although investigators are a long way
from being able to repeat this feat for visible light, this
demonstration suggests that such a cloaking device could, at least
in theory, be possible.
Schurig, D., et al Metamaterial electromagnetic cloak
at microwave frequencies. Science 314:997-980 (November 10)