We often think of species as separate and distinct, but sometimes they can interbreed and create hybrids. When this happens consistently in a specific area, it forms what's known as a hybrid zone.

In the hybrid zone that encompasses the Lehigh Valley in Pennsylvania, the habitats of the Carolina Chickadee and the Black-capped Chickadee converge, creating an opportunity for the different species ...

Side by side comparison of the golden-collared manakin (left), the white-collared manakin (right), and a hybrid (middle) taken from the genomic center, where hybrids are most genetically mixed yet ...