The number of eggs a bird lays — its clutch size — varies greatly among species. You might think every species should simply lay lots of eggs because that would increase the odds of more young birds ...

Egg-collecting enthusiasts in the late 1880s knew the hobby was crucial for understanding the natural world, but likely never imagined that their research would help scientists more than 100 years ...

A once-extinct bird is laying eggs in the wild for the first time in nearly 40 years. Sihek, a now-endangered bird returned to the wild in 2024, has laid wild eggs in its new home in Hawaii, according ...

Who knew that eggs could be so beautiful?

Female lineages of European cuckoos lay eggs with colorful shells and intricate patterns specialized to deceive more than 100 avian hosts into fostering their chicks. Parasitic cuckoo eggshells show ...

Fork-tailed drongos have a signature color and pattern on their eggs, which helps them avoid getting duped by African cuckoos. Hans Stieglitz via Wikimedia Commons under CC BY-SA 3.0 Cuckoos have ...

Black birds with a greenish sheen and brown heads sometimes visit my yard during spring migration. These are male brown-headed cowbirds, and they often arrive in mixed flocks of red-winged blackbirds ...

"It's hard not to feel like a proud parent seeing them out there thriving and making history," London Zoo bird keeper Charlotte James said Jonny Shepherd/TNC-ZSL; TNC-ZSL The once-extinct Sihek bird ...