Measurements with a magnetometer aboard the NEAR-Shoemaker spacecraft a few days after it landed on the asteroid 433 Eros confirmed a major puzzle: The rock has no detectable magnetic field. (p. 341)

A tiny fossil skull found in 195-million-year-old Chinese sediments provides evidence that crucial features of mammal anatomy evolved more than 45 million years earlier than previously thought. (p. 324)

Chunks of fossil charcoal found in ancient sediments in north central Pennsylvania suggest that cycles of wildfire plagued Earth more than 360 million years ago. (p. 309)

A variety of filamentary structures on the fossil of a small theropod dinosaur recently found in China may provide new insight into the evolution of feathers. (p. 262)

Construction of the Three Gorges Dam across the Yangtze River in China may lead to warmer temperatures in Japan, because any diversion of water for Chinese agriculture could initiate convection in the Japan Sea that brings warmer water to the surface. (p. 245)

New observations of the middle and upper atmosphere over Earth's polar regions may require scientists to revamp their mathematical models of temperature and other environmental conditions at high altitudes. (p. 215)

Scientists have found microorganisms within Kentucky shale that are eating the ancient carbon locked within the rock, a previously unrecognized dietary habit that could have a prevalent role in the weathering and erosion of similar sedimentary rock at many other locations. (p. 198)

Using tree-ring analysis, an international team of researchers has reconstructed the earliest record of annual climate variation. (p. 197)