Most birds have distinct calls that tend to stay the same. It’s how birders can recognize a species without seeing it. But new research shows these tunes can change. Over the course of two decades, ...

What Does a House Sparrow Look Like? The male house sparrow has a gray and rusty crown with pale cheeks and a black bib. Reader Patrice Iacovoni of Waterford, Michigan, shared a photo of a female ...