A Pennsylvania birder spotted the bird of a lifetime in his backyard this past spring—it was a hybrid of three species across two genera in a single bird. He’d found a three-in-one warbler.
Natural hybrids can be of conservation concern, since animals mating with the wrong species can give birth to sterile offspring or birds that no one wants to mate with. But one hybrid warbler seems to have found love, albeit with a bird from a completely different genus, leading to the strange results.
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[Birder Lowell Burket and ornithologist Dave Toews] successfully caught the bird in a net and took a blood sample before letting it free. Toews ran an analysis of the bird’s mitochondrial DNA, and found what he was looking for—a Vermivora warbler mother—he presumed a golden-winged warbler—had mated with the chestnut-sided warbler. But when he shared his results with his colleagues and Twitter followers, they asked him to keep going. Mitochondrial DNA only stores information on the maternal lineage, so it wouldn’t reveal whether the strange bird’s mother was a hybrid herself or not.Further testing revealed that Toews’ Twitter followers were right: The mother was a hybrid herself. Burket’s bird was thus three species and two genera in a single bird.
Read full, original post: DNA Testing Reveals Baffling Bird Is Three Species in One