A resurgence of bugs in streams contaminated by a sulfur mine shows that cleanup efforts are restoring water quality and creating a healthy ecosystem.

The agony of a ghost limb can be all too real for amputees. But recent experiments suggest that an unreal treatment may hold the key to a cure.

Amnesiac patients have difficulty imagining future events, new research suggests, implying that memory and imagination are closely related.

This week: new stem cell source found, 2007 may be hottest year on record, Louisiana slipping into Gulf, fish smell their way home, new bat discovered, and more.

Stem cells that can grow into a variety of human tissues have been discovered in the fluid that surrounds a fetus during pregnancy, researchers say.

A U.S. food safety agency proposal to legalize sales of meat and milk from clones has reignited debate over the safety and ethics of animal cloning.

A study spanning seven years of emergency room reports from a Welsh hospital reveals that kicks deal more damage than punches or hits with weapons.

This week: Arctic sea ice may be gone in summer by 2040, no-pain disorder decoded, mammal may have glided before birds, wild new species discovered, and more.

Who says superheroes don't exist? In China a towering shepherd used his extra-long arms to pull plastic from two dolphins' bellies—succeeding where veterinarians had been powerless.

People born with an insensitivity to pain could help researchers understand how pain works and one day develop new painkillers with fewer side effects.

The Gospel of Judas unveiled. A "lost world" of animals discovered. Explore these and other highlights of the year in nature, science, and exploration with our most popular news stories of 2006.

A deadly synergy between HIV and malaria appears to be fueling the spread of both diseases in Africa, where 4 million people die from the illnesses each year.

U.S. officials are looking in the wrong place to stop bird flu, suggests a new study, which questions the usefulness of testing Alaskan birds migrating from Russia.

Curing blindness and treating diabetes "naturally" in mice are just two of the recent breakthroughs that suggest stem cells hold real potential for helping humans.

This week: Al Gore interview, wasps' "pepper spray" weapon, pre-Inca tomb discovery, chemical secret of Stradivarius violins, new butterfly species, and more.