hybridization

Hybridization and disease spread between wild ancestors and domestic descendants is a global issue affecting conservation and pastoral livelihoods -- even in the United States, where bison and bighorn sheep can become susceptible to disease when exposed to domestic partners or vice versa.

Herders sometimes favor hybridization because genes from wild progenitors are thought to enhance the hardiness of domestic stock.

"From the perspective of genetic diversity, hybridization poses a potential threat to the wild ancestors because continuous introgression with the domestic relatives may gradually erode the genetic integrity of the wild forms, leading to the dilution of the wild gene pool over time," Kusi said.

Baker notes that the lineage that led to blueberries, for instance, is the result of an ancient hybridization between dogwoods and the ancestors of coffee plants, daisies, and mints.

This phenomenon, known as subspecies hybridization, can be an important path for species to adapt to a changing environment.