Skip to main content

Subscribe to Smithsonian magazine and get a FREE tote.

Rodents and Shrews

A side view of a "xenocortical" mouse brain, with the grafted human tissue seen in green and red.

Scientists Created Mice With Half-Human Brains. The Hybrid Animals Could Revolutionize Our Understanding of Neurological Disorders

Our brains and their associated diseases are notoriously hard to study. So researchers developed an animal model with a cortex—the brain’s outer layer—grown from human-derived cells

Two yellow-bellied marmots ended up in the San Francisco Bay Area.

Two Chonky, Mountain-Dwelling Marmots Were Found in the Bay Area. What Were They Doing So Far Away From Their Home?

The two rodents of unusual size, rescued this month, might have hitched a ride in the engine compartment of a vehicle coming down from the mountains, wildlife officials say

Since calorie restriction is known to slow aging, researchers wanted to know if GLP-1s—which curb appetite—could do the same.

GLP-1 Weight-Loss Drugs Can Slow Aging and Extend Life Span, Mouse Study Suggests

Older female mice—equivalent in age to 60-year-old women—given daily injections of the active ingredient in Ozempic lived about 12 percent longer than animals that didn’t receive the drug

Marmots can spend up to eight months in hibernation, so packing on the pounds during the short alpine summer is essential to their survival.

Cast Your Vote for the Chunkiest Alpine Rodent During Colorado’s First-Ever Fat Marmot Week

The inaugural competition puts eight yellow-bellied marmots head-to-head while shining a light on the science behind their seasonal weight gain and survival at high elevations

A long-clawed shrew seen in northern Japan

These Tiny Shrews Grow Bigger Snouts and Shrink Their Brains to Survive Harsh Winters, Study Suggests

Scientists have long known that some small mammals reduce their brain size during cold months and regrow them in the spring. Long-clawed shrews from Hokkaido, Japan, seem to follow that pattern—while their noses surprisingly do the opposite

A pregnant naked mole-rat queen, on the left, and a worker, on the right, sniff each other.

Naked Mole-Rat Queens Emit a Special Scent to Stop Their Rivals From Reproducing, a New Study Suggests

The strange-looking creatures are one of two known mammals that use a social structure like that of bees and ants. A ruling rodent maintains power over her colony via one key chemical compound, according to new research

Andean leaf-eared mice can survive in extremely high-altitude environments with frigid temperatures and little oxygen.

Here’s How These Adorable Mice Can Live at an Extremely High Elevation Where No Other Mammal Is Known to Reside

The Andean leaf-eared mouse has adaptations that help it generate body heat efficiently in frigid, low-oxygen conditions at 22,000 feet above sea level, according to a new study

One-celled algae called diatoms are unique because their cell walls are made of transparent silica, like glass, allowing their internal patterns to be visible. Diatoms are key producers of atmospheric oxygen and uphold the aquatic food chain.

See 17 Intricate Microscope Photographs That Make the Miniature World Immense. They Won the Evident Image of the Year Contest

The sixth annual competition showcases scientific microscopic imaging, illuminating tiny parts of nature, from individual cells to arthropods, diatoms and a zebrafish brain

An illustration of an Alston’s singing mouse from the 1882 publication Biologia Centrali-Americana: Mammalia

These Singing Mice Squeak Back and Forth—and Don’t Interrupt. Scientists Found the Brain Pathway Behind Their Impressive Songs

Alston’s singing mice carry out complex vocalizations and even appear to converse politely with one another. The neural circuitry that makes this possible is simpler than researchers expected

The MV Hondius, the cruise ship facing a hantavirus outbreak, anchored off the coast of Cape Verde, an archipelagic country near West Africa

A Deadly Outbreak of Hantavirus Has Stranded a Cruise Ship in the Atlantic Ocean. Here’s What to Know About the Rare Contagion

Three people associated with the vessel have died, and health officials have identified a total of two confirmed cases and five suspected cases of the infection. The virus usually spreads via contaminated rodent droppings

The researchers studied a wetland shaped by Eurasian beavers in Switzerland.

Beavers Are Ecosystem Engineers—and They Might Be Helpful Allies in the Fight Against Human-Caused Climate Change

New research suggests that wetlands created by the industrious rodents are carbon sinks, meaning they store a lot of heat-trapping carbon dioxide—the human-produced gas largely responsible for today’s global warming

Scientists have long assumed that queen transitions in naked mole rat colonies were always chaotic and violent. But new research suggests another, more peaceful path also exists.

Naked Mole Rats Usually Duke It Out to Choose Their Next Queen. But These Unusual Rodents May Be Capable of More Peaceful Transitions of Power

In a laboratory experiment centered around a colony known as the Amigos, researchers observed a subordinate female take over reproduction without incident

Biologists with the California Department of Fish and Wildlife are working hard to eradicate nutria from the state.

Large Invasive Rodents Are Wreaking Havoc in California. New Research Suggests Someone Deliberately Introduced Them

Genetic testing revealed that nutria living in California since 2017 are most closely related to a population in central Oregon—too far for the creatures to have traveled on their own

Magawa the rat detected unexploded ordnance in Cambodia

A Small Rodent Hero Left a Giant Legacy. Now, Cambodia Honors This Famous Bomb-Sniffing Rat With a Seven-Foot Statue

Magawa the African giant pouched rat cleared more 1.5 million square feet of land mines during his five-year career, making him one of the most successful bomb-sniffing rodents in the country’s history

Rats and other rodents have front teeth that grow continuously, so they gnaw to keep them healthy and in shape. 

Rodents Don’t Gnaw Just to Trim Their Teeth—It Also Feels Good, According to a New Study

The findings could help humans who grind their teeth or clench their jaws

A polar bear cub walks along the ice in Svalbard, Norway.

See 24 Astounding Images From the Wildlife Photographer of the Year Contest—and Vote for Your Favorite

The public will choose the winner of the People’s Choice award in a vote that runs from February 4 to March 18

Naked mole-rats are unusual for their long lives and resistance to cancer. Now, researchers suggest the rodents not only tolerate but prefer to be in low-oxygen air.

Naked Mole-Rats Prefer Low-Oxygen Air That Would Kill Most Mammals, Adding to Their List of Death-Defying Superpowers

These underground rodents are the first mammals found to actively choose air with lower-than-normal oxygen levels. Their remarkable ability to survive these conditions could offer a key model for researchers studying new treatments for stroke or lung diseases in humans

Ancient bees built nests in the hollows of rodent skulls, a new study suggests

Fossils Suggest That Some Ancient Burrowing Bees Made Their Homes in Rodent Skulls

While cleaning fossils retrieved from a cave on a Caribbean island, a researcher noticed something strange in the hollow tooth socket of a small skull

A Laysan albatross checks on its egg.

Stream the Beautiful Highs and Violent Lows of Albatross Life With This New 24-Hour Camera on Midway Atoll

You can see the large white seabirds dancing, preening, feeding and raising young—though the live feed might show a dark side of island living, too, with potential predation from invasive mice

Bat? Meet rat. Scientists recorded brown rats snatching bats from the air and eating them.

Rats Are Snatching Bats Out of the Air and Eating Them—and Researchers Got It on Video

Rodents in northern Germany were spotted using two different hunting strategies at major urban bat hibernation sites

Page 1 of 7