Human activity appears to be causing two related species of songbirds to mate.
The research finds disturbances to the habitats of the black-capped and mountain chickadees are leading to this hybridization in the Mountain West.
The Show spoke with Kathryn Grabenstein — a post-doctoral research associate at the University of Colorado at Boulder who worked on the study — and asked what led her to look into this hybridization among these different kinds of birds.
