The holy grail of batteries is one powerful enough to run an electric car 300 miles on one charge. A new book talks about the global race to do so.
Years after the first human case of the brain disorder, there's worry over a second outbreak.
Females are left to rear ducklings while male mandarin ducks get together for a molting party.
From young love in Switzerland to a sweet embrace in Paris, see our collection of kissing photos.
One California family talks about their fears, and why they have staggered some vaccinations.
Asian elephants, magpies, and great apes are among the species that can recognize their own images in the looking glass.
Every day is Valentine's Day for the gold swift moth, which may have the most advanced mating system of any insect.