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Mammals

The Best Places to See Reindeer Around the World

From Norway to Alaska, here’s where to see members of Santa’s herd in person

The jumping spider bears a distinct resemblance to ants

Jumping Spiders Are the Only Arachnids Known to Provide ‘Milk’ For Their Young

The milk-like nutritious fluid contains four times the protein of cow’s milk

Baleen is the soft, hair-like structure on the upper mouth of whales, such as the humpback whale in this photo, which allows them to trap prey in their mouth.

Prehistoric Whale Jaw Bone Sheds Light on the Evolution of Baleen

Hidden in a museums’ collections for years, a fossil provides a link between past and present feeding mechanisms

Cool Finds

Early Mammals Were Thought to Be Small and Unseen in the Age of Dinosaurs. An Elephant-Sized Fossil Complicates That Story

At a time when proto-mammals and other creatures were getting smaller, this dicynodont bulked up with the thunder lizards

A figure representing the Kayentatherium babies found with an adult specimen. They are the only known fossils of babies from an extinct mammal relative that lived during the Early Jurassic.

Weasel-Like Fossils Reveal Evolutionary Clues of the First Mammals

A protomammal known as Kayentatherium was discovered with 38 babies in 185-million-year-old rock

Princepajaro, a male California sea lion, swims in a pool during treatment for leptospirosis at The Marine Mammal Center in Sausalito, CA. When a leptospirosis outbreak occurs, the Center’s scientists study the disease to learn more about what causes an outbreak and how we can improve treatment for infected animals.

Major Disease Outbreak Strikes California Sea Lions

Leptospirosis afflicts sea lions on a semi-regular cycle, but warming waters and migrating fish could make the marine mammals more susceptible

Buffaloes at Rest recalls a time when bison were plentiful. When the print was created in 1911, only about 1,350 remained.

The Bison Returns to the Great American Plains

After years of fierce debate, the West’s greatest symbol will again roam the countryside

Hormone signals help ready worker mole-rats to treat pups as their own.

Eating the Queen’s Poop Makes Naked Mole-Rats Better Parents

Hive-minded naked mole-rats work together to care for the queen’s offspring, and eating her poop gives them hormones to boost nurturing instincts

Asian elephants have less than a 33 percent chance of lasting beyond the 21st century

Earth Lost 2.5 Billion Years’ Worth of Evolutionary History in Just 130,000 Years

Even if humans curbed destructive actions within next 50 years, it would take between five to seven million years for mammal biodiversity to fully recover

Feast your eyes on the blind Somalian cavefish, which has—like mammals—mysteriously lost the ability to use light to fix damaged DNA.

Blind Cavefish Shed Light on the Dark Days of Mammalian Evolution

Like mammals, these cave-dwelling creatures have discarded a solar-powered system that repairs UV-damaged DNA

Sloths' slow-paced lifestyle is a survival strategy, not a sign of laziness

Sloths Don’t Just Live in Slow-Mo, They Can Put Their Metabolism On Pause

Unlike most mammals, sloths don’t use vast amounts of energy when it’s hot, instead opting to slow down and conserve power, more like birds or reptiles

Trending Today

Five Baby Squirrels Saved From Truly Knotty Predicament

Five gray tree squirrels in Wisconsin were found with their tails hopelessly knotted together, requiring some help from a wildlife rehab

A jaw of an Eoconodon coryphaeus—a house cat-sized omnivore that lived between about 66 and 63 million years ago—that Williamson collected in the San Juan Basin.

Nuclear Technology May Help Bring Early Mammal Evolution Into Focus

Using a neutron scanner at Los Alamos, paleontologists are generating high-resolution imagery of early mammal fossils

These wrinkly rodents continually surprise researchers.

How Eating Poop Makes These Mole-Rats More Motherly

New research suggests a colony’s queen stimulates babysitters by transferring a type of estrogen through her feces

Two tacos, extra ghost pepper sauce, please!

New Research

Tree Shrews Love Hot Peppers Because They Don’t Feel the Burn

A genetic mutation prevents Chinese tree shrews from feeling the heat of capsaicin, making them the only other mammal besides humans that enjoys hot foods

New Research

Coral Reefs Need Fewer Rats and More Bird Poo

A study of rat-infested islands in the Chagos show that a lack of seabirds—and their guano—degrades surrounding coral ecosystems

This scrotal male certainly isn't sheepish.

New Research

The Earliest Mammals Kept Their Cool With Descended Testicles

But if free-swinging sperm sacs are the norm, then why did undescended ones evolve four separate times?

Do Marine Mammals Yawn and More Questions From Our Readers

You asked, we answered

Why People Believed Hippos Were Related to Whales

Hippos were once believed to be related to whales. They’re both mammals, they both sleep underwater, and they both rise to breathe in their sleep

I can haz more habitats?

New Research

The UK’s Hedgehogs (and Other Mammals) Are In Danger

The island nation’s mammal populations have seen a steep decline in the last two decades, with hedgehog numbers decreasing by two-thirds

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