|
Comment on this article
Noted
May/June 2009
Exercising
self-control is tough enough, but according to psychology professor Joshua
Ackerman, the simple act of watching -- even imagining -- another person trying to
exert self-control can exhaust the viewer's own capacity for restraint.
Ackerman and colleagues report in the March issue of Psychological Science on experiments demonstrating this
"vicarious depletion" effect.
Knowing
that butterflies' wing markings can both frighten predators and attract mates,
Darwin theorized that the markings on the lower surface evolved to frighten and
the markings on top to attract. Jeffrey Oliver, a postdoctoral researcher in
ecology and evolutionary biology, and colleagues have now confirmed that he was
probably right. Their analysis of Bicyclus butterfly specimens showed the lower and upper
surface markings evolved at different rates -- a sign they were responding to
different evolutionary pressures. The work appeared online on April 1 in the Proceedings
of the Royal Society B.
The
most credible climate models show that in 30 years, the Arctic will be ice-free
in summer. But according to Yale ice physicist John Wettlaufer and Caltech's
Ian Eisenman, there won't be a catastrophic tipping point in this process
because of a feedback loop that lets winter ice grow back faster when summer
ice has thinned. The work appeared in the January 6 issue of the Proceedings
of the National Academy of Sciences.
The
use of another creature's cast-off shell for portable housing may greatly
predate the hermit crab. For a study in the April Geology, geologist Adolf Seilacher and
Amherst paleontologist James Hagadorn analyzed 500-million-year-old fossilized
tracks. They found that the first arthropods to colonize the land carried
shells from other animals, probably for protection from the elements. 
|