The first hints that a new strain of avian illness is emerging could be found on this beach on Delaware Bay, where migrating birds flock. Here’s what virus detectives who return there every year know right now.

As more men turn to testosterone replacement therapy (TRT) for energy, mood and muscle, experts warn the risks are still not fully understood.

We’ve all heard the saying “you are what you eat”—especially when it comes to gut health. But what if your workout matters just as much as your diet?

Major changes hit a key CDC vaccine advisory panel, ocean acidification crosses a critical threshold, and new research reveals an unexpected threat to pangolins.

Are These Hamsters the Best Dads in the Animal Kingdom?

Could the spectrum of animal lifespans hold clues about the science of aging?

The Milky Way’s big crash with Andromeda might not be a sure thing. Plus, we discuss an overheated ocean, a giant planet circling a tiny star and worms that build living towers.

What happens when the U.S.’s most trusted source of extreme weather alerts can’t staff the night shift?

It’s one step forward and two steps back for vaccine policy in the U.S. Plus, we discuss the fishy origins of sensitive teeth and megalodon diets.

Young people are struggling; retirees are happier than employees; people in partnerships are flourishing more than those who are single. Hear the first takeaways from the Global Flourishing Study.

A new study suggests a way to more accurately test sperm health from home.

Unraveling the Clicks From the Whistles

New discoveries about mitochondria could reshape how we understand the body’s response to stress, aging and illness.

Also, Chimp "Prosocial Postcoital Penis Wiping"

Refreezing the melting sea ice in the Arctic is more complicated than you would think. The U.K. is funding geoengineering experiments like this one to curb the effects of climate change.

High vaccination rates eliminated measles in the U.S. An outbreak that began in West Texas is threatening to overturn that status.

A spacecraft is set to fall from the skies, 28 U.S. cities slowly sink, and a new study pinpoints how the overindulgence of the wealthy contributes to massive warming.

How the Nation’s Only Particle Collider Is Accelerating Our Understanding of Physics

Author Casey Johnston presents a new way to think about fitness in her new book A Physical Education

Climate studies are paused, new satellites join the crowded skies, the Juno spacecraft studies Jupiter, and biotech companies will create T. rex leather (or will they?).

As conservation targets, fungi aren’t as appealing as giant pandas. But these scientists explain that the health of Earth’s fungal species is critically important.

We present a historical romp through Scientific American—100 years ago.

Finding Wondrous Wildlife Amid the Concrete Jungle

In a new book called Slither, Stephen S. Hall takes a deep dive into the biology and history of one of the most reviled animals.