A vast "baby-making" operation may give five endangered mussel species their last, best hope for survival on Tennessee and Kentucky's Big South Fork River.

Rodent numbers are expected to surge in the U.S. Southwest next year and drive an outbreak of deadly Hantavirus, one expert says.

Find out why scientists think sharks occasionally attack people, and discover which mammals the massive fish literally flip for.

Studies of animal-eye evolution may yield cutting-edge optical technologies for the 21st century.

Magellanic penguins in Argentina are "holding steady" after decades of decline due to polluted seas and commercial overfishing, biologists report.

Squeezed into a six-figure shark costume, explorer Fabien Cousteau—Jacques's grandson—dove among great whites for the new TV special Shark: Mind of a Demon.

A 150-million-year-old fossil of Archaeopteryx, long considered the oldest bird, may put to rest any scientific doubt that dinosaurs gave rise to modern birds.

Poultry vaccines can prevent healthy chickens from contracting deadly strains of avian influenza, Dutch researchers report.

The wild reservoir of the deadly Ebola virus has been traced to three fruit bat species in central Africa, scientists say.

A new study suggests that having too many males of one species could lead to more sexual aggression toward females and spur extinction.

Tracks of a human-size water scorpion discovered in Scotland offer the first evidence that the giant creatures walked on land, scientists say.

Normally cautious mice can be turned into daredevils by removing a gene in their brain that regulates fear, a new study has found.

Learn how a Singapore zoo is providing an "insurance policy" for the survival of the highly endangered proboscis monkey.

New research into the tusks of mammoths is shedding light on what the giant animals ate, how long they nursed, and someday, scientists hope, why they vanished.

Some warblers in Europe are canceling their annual winter breaks in Africa, opting instead to fly to Britain for the holidays.