Analyses of the gases dissolved in water trapped in ancient minerals suggest that methane-generating microbes have been around almost 3.5 billion years. (p. 179)

A second, modified course of drug treatment fosters recovery in a substantial minority of depressed adults who don't feel better after treatment with a commonly prescribed antidepressant. (p. 179)

Despite the doubts of some botanists, plant species aren't just some arbitrary human classification scheme, says a team of evolutionary biologists. (p. 180)

A genetic test not available in the United States catches many potentially cancer-causing BRCA-gene mutations not detected by the sole U.S. test. (p. 180)

The December 2004 tsunami had little geological impact on the seemingly fragile coral-reef islands of the Maldives archipelago. (p. 181)

A new type of superfluid atom cloud that's been thrown off-balance by having more atoms with their quantum spins pointing up than down, or vice versa, seems to defy theoretical expectations. (p. 181)

The first study of comet dust brought to Earth by a spacecraft has revealed several minerals that could have formed only at the fiery temperatures close to the sun or another star. (p. 182)

A recent crop of studies demonstrates how nature finds strength in unlikely places. (p. 184)

The narwhal's distinctive spiral tusk has structures that could make it phenomenally sensitive, raising new questions about its functions. (p. 186)

The video released last spring as evidence that the ivory-billed woodpecker exists may show a common pileated woodpecker, some critics say. (p. 189)

Astronomers have found clouds of sand crystals resembling crushed glass around 21 infrared-bright galaxies. (p. 189)

Wild capuchin monkeys manage to avoid inbreeding, despite rampant opportunities for high-status fathers to mate with their grown daughters. (p. 189)

The tenacious bonds between two carbon atoms can be broken in a surprisingly simple process. (p. 189)

A common black mold that blooms on moist cellulose-based materials produces a toxin that can kill certain brain cells. (p. 190)

Street grit is the probable source of lead in urban homes, and flaking paint from overpasses and bridges is a major contributor. (p. 190)

Drinking alcohol can greatly compromise the skin's barrier to chemicals. (p. 190)

A study in mice finds that early-life exposure to the fluorinated chemicals used in nonstick products can rewire the brain in ways that dramatically affect behavior. (p. 190)

(p. 191)