Stephanie O'Neill

For most pet primates in the United States, life is marked by chronic stress, malnutrition and illness — if they survive at all. A bill in Congress would aim to make ownership of captive primates illegal in all 50 states.

Wildlife trafficking is one of the world's biggest illegal trades, and the U.S. creates much of the demand for pet primates. Now there's a proposed ban on privately owning and breeding these animals.

In northern California, a group of volunteers spend every night from late fall through winter as crossing guards–escorting migrating salamanders across a rural road.

A group of volunteers spends every night for a few months acting as crossing guards for tiny amphibians: migrating salamanders.

Only about 300 to 400 people a year give a kidney to someone they never met. It's an act of generosity so unusual, a neuroscientist studies the people who do this.

About 300 Americans a year give a kidney to a complete stranger. Research says these people have a larger amygdala -- perhaps making them feel others' pain more than the average person.

More than 90,000 people in the U.S. are waiting for a kidney transplant. But a kidney shortage means many die on the waitlist or become too sick for a transplant. A new plan would compensate donors.

Completing a routine depression screening questionnaire during an annual checkup is cost-free under federal law. But, as one woman discovered, answering a doctor's follow-up questions might not be.

Some doctors and medical practices voluntarily give rebates on a bill if an injury occurs during a procedure, while others will not, a medical ethicist says. Here's how patients can respond.

William Simpson wants to deploy the wild horses across public lands, to live and graze — and ultimately, prevent the worst wildfires.