Researchers wearing all-white protective gear pose on a green hillside in Sierra Leone.

The Virus Hunters: Finding animal diseases before they infect humans

More than 60 percent human viruses originally come from animals.

For the past decade, these researchers around the globe have been working to identify risky viruses before they infect humans.

The team found a new Ebola virus in bats in Sierra Leone, and has worked with various communities to reduce exposure.

A white man's hands holding a small piece of a water plant, with shallow water of lake in the background.

Invasive aquatic plants threaten Lake Tahoe’s clear waters

The plants look like seaweed, rising from the shallow areas of Lake Tahoe to the surface. But in this fresh-water, high-mountain lake with a $5-billion recreation economy, invasive plants threaten both the environment and an international tourist destination.

A diagram shows how the human heart can change shape under stress from a romantic loss.

The Anatomy of a Broken Heart

A traumatic emotional event can cause the heart to change its shape and become less efficient. It’s called “broken heart syndrome” for a reason.

Several people carrying equipment walk single-file through a meadow of tall grass toward trees at the back.

Meadow ‘sponges’ can help store water as snowpack shrinks

A project to restore a damaged meadow in the Sierra Nevada shows the possibilities for improving an important mountain ecosystem. It can also store precious groundwater as climate change shrinks mountain snowpack, a vital source of fresh water in the American West.