Falcons and parrots linked; bird study full of surprises

CHICAGO — When a falcon swoops from the sky to seize its fleeing prey, no one would mistake the sleek predator for a gaudy parrot.

Yet the secret kinship of falcons and parrots is one of many surprises in a landmark genetic study of 169 bird species being published by Field Museum researchers.

One likely consequence of the study in Friday's edition of the journal Science is a reordering of the field guides that many of America's 80 million bird-watchers use. Most bird guides are based on scientific classifications, which experts said the new work could change.

"This is the most important single paper to date on the higher-level relationships of birds," said Joel Cracraft, curator of birds at the American Museum of Natural History in New York, who was not part of the study.

Birds are all around us, having evolved into a dazzling variety of forms in every part of the world, but the chore of mapping their family tree has long stumped scientists. Many previous studies relied on painstaking comparisons of outward characteristics and behaviors, which often fail to reveal true relationships.

Genetic comparisons can tell a deeper story, so the Field Museum launched a five-year effort with seven other institutions to do an unprecedented genetic analysis using powerful computers. They discovered many cases in which seemingly similar birds were merely distant relatives, or birds long assumed to be unrelated were closely linked.

Grebes, a type of diving bird, are not related to loons, as ornithologists had thought. Surprisingly, grebes appear closely related to flamingos.

The analysis also showed falcons are more closely related to parrots than to other hunters such as hawks and eagles. If true, the finding would mean falcons do not even belong in the scientific order originally named for them.

"It's kind of crazy to us, too," said Shannon Hackett, a lead author of the study and associate curator of birds at the Field Museum. "People have been studying birds a long time, but now we're in a time when we should question everything, because for the first time we have the tools to answer these questions."

The project was part of a federally funded effort called Assembling the Tree of Life, which aims to trace the evolutionary origins of living things.