CRISTINA BYVIK / Union-Tribune

What's Inside Eureka! Sagittarius marks coming of autumn Questions answered Crows can see something in us Southwestern U.S. gets drier weather Margaret Cho and her people are focus of L.A. reality show A week of golden moments for NBC Everyone possesses power to make world less crazy, scary More Quest

The poet Joyce Kilmer was right: “Only God can make a tree.” Klaus Lackner just wants to make it better. Lackner, a geophysicist at Columbia University in New York, doesn't actually want to make trees. Rather, he wants to build devices that mimic one of the things real trees do: extract carbon dioxide (CO_²) from air.

What happens after you eat hot chile peppers reads like a list of drug side effects: burning pain, sweating, teary eyes and panic followed by lingering numbness. The plant makes its mouth-torching ingredients, called capsaicinoids (cap-SAY-sin-oyds), to stop animals from munching its fruit, biologists say. Strange, then, how human cooks have avidly embraced the chile for more than 6,000 years.

The eight tentacles of an octopus divide up into six “arms” and two “legs,” scientists report. The creatures seem to favor their first three pairs of tentacles for grabbing and using objects. Unlike humans and some other animals, most octopuses do not appear to be left-handed or right-handed.