▪ The bee's knees: In the first demonstration that insects can learn by watching, bumblebees seeing fellow buzzing foragers on certain flowers were twice as likely to forage on those flowers.

Biology Letters of the Royal Society online, August 19

▪ The earth's core appears to be rotating faster than the rest of the planet by up to 0.5 degree a year. The possible cause: the liquid outer core's magnetic field that tugs on the solid iron inner core.

Science, August 26

▪ Using alcohol-based hand-sanitizing gels reduces the incidence of gastrointestinal infections by 59 percent.

Pediatrics, September

Space rocks could affect local weather: a 10-meter-wide asteroid that burned up over Antarctica left micron-size dust particles in the upper atmosphere—big enough to seed clouds and to cool the air by reflecting sunlight.

Nature, August 25