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Reproduction

In loud conditions, a tokay gecko adjusts its call, which is typically used to find a mate or defend territory.

Reptiles Make a Surprising Amount of Noise. Here’s What Those Sounds Might Mean, From Pops to Hoots to Bellows

Scientists are realizing that turtles, lizards and crocodilians communicate vocally more than they once thought

A male Cope's gray treefrog is smaller than a female and attaches to her back as she looks for a spot to lay eggs.

Female Treefrogs Experience ‘Choice Overload’ Amid Too Many Mating Calls From Males

Faced with a chorus of potential mates, female Cope’s gray treefrogs may be overwhelmed by the number of options and struggle to make a careful decision, a study suggests

The right side of the bird's body is male while the left side is female.

An ‘Extremely Rare’ Half-Male, Half-Female Bird Temporarily Took Up Residence Outside of Chicago

The unusual-looking bobolink is what’s called a bilateral gynandromorph. The bird behaved like a male, eventually wooing a mate and raising fledglings

An illustration of Chiniquodon theotonicus, including a pregnant female and a nursing female

When Did Animals Start Giving Birth to Live Young? This 236-Million-Year-Old Fossil Might Rewrite Mammals’ Evolutionary History

A bone feature found in a mammal ancestor hints that the creature was relatively large as a newborn, more in line with the size of a creature birthed live than hatched from an egg. Still, it provides only indirect evidence

Redback spiders live throughout Australia.

Here’s Why These Male Spiders Sacrifice Themselves by Somersaulting Into Females’ Fangs While Mating

A new study suggest that even strange, complex animal behaviors can have a relatively simple genetic basis

Keepers and veterinarians are monitoring Milani around the clock.

A Premature Baby Giraffe Born Via C-Section Is Fighting for Her Life at a Zoo in Kansas

According to officials with the Tanganyika Wildlife Park, no known giraffe calf has ever survived the procedure. The youngster, who was recently named Milani, was born on July 11, likely three to seven weeks early

A mother floating belly-up next to her calf

Why Are These Whales Floating Upside-Down? They Might Just Be Moms Who Need a Break From Feeding Their Babies

Each year, southern right whales migrate thousands of miles from their feeding grounds to breed, give birth and raise their young. Taking rests and regulating their calves’ nursing schedules might help mothers conserve energy while they’re far from food

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 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

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