
AnimalsSeptember 17, 2024
Chickadees Show How Species Boundaries Can Shift and Blur
When different chickadee species meet, they sometimes choose each other as mates—with surprising results
Rebecca Heisman is a freelance science writer who specializes in ornithology and bird conservation. She is author of Flight Paths: How a Passionate and Quirky Group of Pioneering Scientists Solved the Mystery of Bird Migration (HarperCollins, 2023).

Chickadees Show How Species Boundaries Can Shift and Blur
When different chickadee species meet, they sometimes choose each other as mates—with surprising results