Some female animals—including fish, snakes, and octopi—store sperm in their reproductive tracts for years after mating. But why?
He’s big. He’s slimy. And he’s … neon pink?! Meet Triboniophorus aff. graeffei, a new species of 8-inch-long (20-centimeter-long) slug.
Arrrr! The pirate ant, a new species from the Philippines, comes complete with eye patches.
The mysterious arrival of a zoo anteater has some talking virgin birth, or parthenogenesis. See what other animals have babies without fathers.
Vampire bats can identify other bats by their voices—just like people, a new study says.
Female spiders are usually thought of as femme fatales—but male spiders of some species also eat their mates, a new study says.
A newfound fairyfly that’s 0.01 of a inch joins a crew of the world’s smallest, including a bumblebee bat and a mouse lemur.
If you thought the battle of the sexes was chaotic, meet Tetrahymena thermophila, whose genetic mysteries are finally being revealed.
Female Ulidiid flies expel and eat ejaculate as a way to control who will father their offspring, a new study says.
People have been using manure as fertilizer for millennia. But scientists now believe they can turn human urine into liquid gold—as composting material.
Dolly Varden trout can expand their organs to more than two times their regular sizes, a new study says.
Worms that eat dead whales at the bottom of the ocean also mate inside the bones, a new study shows for the first time.
Talk about a bottom feeder—the giant California sea cucumber uses its butt as a second mouth, a new study says.
A newfound ancestor of modern bugs has some pretty bizarre traits—its legs are under its mouth, and its spine extends far above its brain, a new study says.
Ancient urine of a rabbit-like critter is revealing how Earth’s climate changed thousands of years ago.
Find out how Lu, the injured loggerhead sea turtle, got her sea legs back thanks to prosthetic limbs developed by a Japanese team.
Eelpouts, rattails, and cusk eels were among the odd haul of species discovered during a recent expedition to the Kermadec Trench.
Dozens of readers have suggested a name for a newfound species of decoy-building spider. What would you call it?
Talk about a web of deceit—biologist Phil Torres has found a spider that weaves a bigger decoy “spider” to scare predators.