A look back at 2025’s biggest science stories—from federal upheaval and public health setbacks to climate policy reversals and groundbreaking discoveries in space.

Researchers uncover 20 new underwater calls from Hawaii’s endangered monk seals.

A scientist, a journalist and a remarkable scent‑detecting dog race to learn what’s endangering the last southern resident orcas.

This week’s science roundup covers 2025’s near-record heat, a new mpox strain and fresh clues about why hobbits vanished 50,000 years ago.

Journalist Karen Hao unpacks the rise of AI “empires,” their ideological roots, and the hidden environmental and societal costs of OpenAI’s quest for artificial general intelligence.

NASA’s Perseverance rover has gathered groundbreaking Mars samples, but the mission to bring them home is facing serious challenges.

Vaccines coming under fire, satellites crowding the skies, and dogs boosting teen mental health.

This Two-Week Treatment May Reset the Brain

Scientific American unveils its first-ever best fiction and nonfiction books of the year, spotlighting stories that blend science, imagination and unforgettable voices.

Wild turkeys once nearly disappeared, but today they’re thriving.

A new study finds that fluoride is safe for kids’ brain—and linked to slightly better test scores.

Witness the Hidden Beauty of Snowflakes, Radiolarians and Lunar Rocks

As holiday feasts and stress approach, an expert explains how to keep your gut healthy without skipping the stuffing.

Scientific American’s editor in chief David M. Ewalt reflects on a 20-year experiment in e-mailing the future.

From COVID shots to cancer therapy, mRNA is changing medicine.

Science writer David Berreby shares his personal journey with griefbots and discusses how they can offer unexpected comfort, insight and connection in the wake of loss.

Kendra Pierre-Louis steps in as interim host and dives into the science behind why some foods—especially mayonnaise—can gross us out.

Migraine and cluster headaches affect millions—yet research remains surprisingly thin.

Why saying no is harder than it should be.

Hurricane Melissa’s rare intensity and lasting impact reveal how storms are evolving in a warming world.

This Halloween discover how your candy choices can trick—or treat—the microbes in your gut.

TikTok’s U.S. spin-off could reshape its algorithm and the way culture is curated online.

Bird flu surges and a government shutdown collide, complicating efforts to track cases and protect flocks.

Despite the widespread use of medication during pregnancy, a lack of clinical research leaves patients and doctors navigating treatment with dangerously few data.

The words we choose when apologizing—especially longer, effortful ones—can signal sincerity and make our apologies feel more authentic.