Tasmanian devils transmit cancer cells when they bite each other during routine squabbles, producing lesions that are often fatal. (p. 67)

By rebuilding a patient's immune system using his or her own stem cells, doctors can reverse of the course of lupus in severely ill patients. (p. 67)

A novel scheme for increasing the number of collisions in particle accelerators has boosted the performance of the world's highest-energy collider. (p. 68)

The same protein that, in an altered shape, causes mad cow disease maintains the body's cache of blood-producing stem cells. (p. 68)

In its first test in people, a vaccine against the toxin ricin appears safe and generates antibodies that are expected to be protective against the potential bioterrorism agent. (p. 69)

Trapped beneath Antarctica's kilometers-thick ice sheet are two immense bodies of water that may harbor ecosystems that have been isolated for millions of years. (p. 69)

Researchers have found an alternative to the livestock drug that has accidentally poisoned a majority of the vultures in India and neighboring countries. (p. 70)

Microbial fuel cells, which take advantage of the fact that some microbes generate electricity when they break down organic matter, could one day power remote sensors, wastewater-treatment plants, and portable devices. (p. 72)

Emerging data indicate that use of pyrethroid pesticides, even by home owners, poses significant environmental risks. (p. 74)

A person's likelihood of developing type 2 diabetes varies seasonally and is about 50 percent higher in March than in August. (p. 77)

Two recent scientific papers have described fish species that could, depending on the definition, be the world's smallest known vertebrate. (p. 77)

Later this century, rising concentrations of greenhouse gases in Earth's atmosphere could slow the ocean currents that bring warm waters to the North Atlantic. (p. 77)

Cells on a tumor's outer layer that touch healthy tissue receive a chemical signal that sends them wandering away. (p. 77)

The largest industry-funded medical trials in history have found that two new vaccines are both safe and effective against life-threatening childhood diarrhea caused by rotavirus. (p. 78)

Drinking water contaminated with manganese can subtly limit a child's intellectual development. (p. 78)

Last year's global average temperature was the warmest since scientists began compiling records in the late 1800s. (p. 78)

A highly elongated group of stars is most likely a dwarf galaxy that is being gobbled up by the Milky Way. (p. 78)

(p. 79)