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Reproduction

When they hatch, echidna puggles are about the size of a jellybean and weigh half as much as a mini marshmallow.

Good News

Double Puggles: See the Adorable ‘Twin’ Echidnas Born at the San Diego Zoo Safari Park

The two babies hatched earlier this year to one mother during the same breeding season—an extremely rare occurrence, according to the San Diego Zoo Wildlife Alliance

Koala conservation is a complex balancing act in Australia. In some regions, populations are in steep decline, but in others, the animals are overabundant.

Koalas Are at Risk of Extinction in Some Parts of Australia. Can Freezing Their Sperm and Eggs Help Save the Iconic Marsupials?

Scientists are preserving the animals’ reproductive cells in liquid nitrogen in a bid to boost genetic diversity in future populations

Dinosaurs and other animals might have eaten the fruits of angiosperms during the Late Cretaceous.

Early Flowering Plants May Have Relied on Dinosaurs to Eat Their Fleshy Fruits and Spread Their Seeds

According to fossils preserved by volcanic ash, the plants, known as angiosperms, began producing relatively large, blueberry-size fruits millions of years earlier than previously thought

A time-lapse of an individual D. melanogaster sperm cell. The head is artificially colored pink, and the tail is teal.

These Male Fruit Flies Have Sperm That Are Nearly as Long as Their Bodies. Here’s How the Cells Don’t Become a Tangled Mess

Males of the species Drosophila melanogaster pack thousands of almost two-millimeter-long sperm cells into significantly smaller storage organs. A new study reveals how they move in an orderly manner

Indo-Pacific bottlenose dolphins live in the tropical waters of the Indian and western Pacific oceans.

Female Dolphins Seem to Remember Which Males Were Aggressive During Mating Season—and May Try to Avoid Them

When researchers played underwater recordings of pushy males, females that were capable of becoming pregnant swam away from the sounds

During and after pregnancy, hormones drive profound changes in the brain’s structure and function.

Pregnancy Changes Mothers’ Brains. These Recent Discoveries Are Showing Us How

“Baby brain” isn’t the deficit it’s stereotyped to be, research suggests. Neural adaptations during pregnancy can prime soon-to-be-moms to become more attuned to their children and enhance social cognition

About 47 percent of wolves in Italy are considered wolf-dog hybrids, according to a recent genetic analysis.

Nearly Half of Italy’s Wolves Are Part Dog Now, Thanks to Hybridization. Is That a Threat to the Species?

Wolf-dog hybrids are growing far more common in Italy, raising scientists’ concerns for the future of the wolves

Andrena regularis, or the regular mining bee, is an important pollinator species.

Scientists Found 5.6 Million Burrowing Bees Beneath a Cemetery in New York. The Group Is One of the Largest on Record

Researchers in Ithaca estimated the number of ground-nesting bees emerging from a local cemetery in spring 2023, revealing just how abundant some understudied pollinators are

The researchers primarily studied California two-spot octopuses.

Octopus Sex Just Got Weirder. In Addition to Depositing Sperm, Males’ Specialized Mating Arm Can ‘Taste’ Female Hormones

The hectocotylus is both a reproductive organ and a sensory organ, a rare combination in animals, new research suggests

Domino the warty frogfish is about the size of a pea.

Meet Domino, a Tiny, Bumpy Fish Making a Splash in Chicago

The warty frogfish, also known as a clown anglerfish, is believed to be the first of its kind born and raised in captivity

Purple martins are long-distance migrants that nest in human-provided boxes across North America.

Purple Martins Rely on Human ‘Landlords’ to Provide Nest Boxes Each Spring. Can That Dynamic Last?

The large swallows have nested alongside human settlements for centuries. Now, the birds’ breeding success depends on caretakers who are beginning to age out of the role

Male reproductive cells, sperm, might struggle to reach and fertilize female reproductive cells, eggs, in microgravity, according to a new study.

Humans Might Struggle to Make Babies in Space. Sperm Gets Disoriented in Microgravity, a New Study Suggests

Simulated near-weightless conditions reduced human sperm’s navigational abilities

Participants listened to pairs of mating calls made by numerous creatures, including male green treefrogs.

Humans and Animals Often Like the Same Mating Calls, Supporting a 150-Year-Old Observation by Charles Darwin

New research by Smithsonian scientists suggests that preferences for certain sounds might be evolutionarily conserved

Male African striped mice's parenting styles vary greatly: Some fathers groom and protect their pups from the elements, while others ignore or even attack their young.

Some Mice Are Doting Dads, While Others Ignore or Attack Their Offspring. Researchers Just Figured Out Why

In African striped mice, the activity of one gene can dramatically change a male’s parenting style, according to a new study

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

A juvenile harbor seal lies on a beach in the Netherlands.

Seals Are Seemingly Vanishing Off the Dutch Coast. These Scientists Are Trying to Get to the Bottom of the Mysterious Disappearances

Recent counts of the Wadden Sea’s adult harbor seal population have revealed a surprising trend of decline, prompting a consortium of researchers to investigate whether the animals are dying off, relocating or experiencing something else altogether

A gentoo penguin peers up from its colony’s nesting grounds on Booth Island, in the Antarctic Peninsula. The species, an adaptable forager that can switch prey when krill are scarce, has expanded into parts of the Antarctic Peninsula that were once too icy to inhabit.

The Penguins That Thrive—and the Ones Left Behind—as Antarctica Warms

A new decade-long study tracked 37 penguin colonies and found that the birds are breeding earlier. The shift marks one way among many that climate change is transforming life at the bottom of the world

The Teal Wand is the only self-collection device for HPV testing approved by the Food and Drug Administration for at-home use.

Many Americans Will Soon Have Access to At-Home Cervical Cancer Screening Tests at No Cost

U.S. guidance announced on Monday recommends self-collection of samples to test for HPV, the virus that often causes cervical cancer. Private insurers must cover the costs of the swab kits by 2027

Male white-tailed deer rub their heads on trees and urinate on scraped-up earth to leave "signposts," which glow under ultraviolet light, a study suggests.

When Male Deer Mark Trees, Those Spots May Glow Like Neon Lights at Dusk and Dawn, Though Humans Usually Can’t See Them

During the breeding season, white-tailed deer might use their eyes and noses to navigate signs—forehead secretions on trees and urine on the ground—left by males of their species, a study suggests

Researchers were surprised when they spotted an additional cub with this mother polar bear.

This Mama Polar Bear Adopted a Young Cub—and You Can Track the Family as They Wander Around the Hudson Bay

The rare event marks the 13th known instance of adoption within this well-studied group of polar bears living in the western Hudson Bay area

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