Off the coast of British Columbia, dolphins lead killer whales to salmon and earn their share of lunch, a new study reveals.

The dogs are part of a mental wellness program that began after a rash of officer suicides. The dog unit’s fate is unclear as Commissioner Jessica Tisch shifts more officers to patrol duty.

© James Estrin/The New York Times

A North Carolina organization delivers salvation on four legs.

At an international conference, researchers at the forefront of animal-human transplantation compared notes and allowed themselves the first real optimism in decades.