Was Archaeopteryx in the Process of Becoming the Earliest Known Flightless Bird?

Although it has long been debated whether the proto-bird Archaeopteryx was able to actually fly or merely evolving toward that ability, to date nobody had yet seriously suggested that it could have been instead in the midst of losing its ability to fly. But that is precisely what Michael Habib, a biologist at the University of Southern California proposed last week to a packed hall at the annual meeting of the Society of Vertebrate Paleontology in Los Angeles.

With the skeleton of a dinosaur and the feathers of a bird, Archaeopteryx has long been hailed as marking the transition from dinosaurs to birds.

The idea that it was instead evolving to lose its flight and becoming flightless again, or 'secondarily flightless', occurred to Habib while he was calculating limb ratios and degrees of feather symmetry in Archaeopteryx, and comparing the values to those of living birds, to better understand its flying ability. In doing so, he found that the creature's traits were surprisingly similar to those of modern flightless birds such as rails and grebes that frequently dwell on islands.

“We know Archaeopteryx was living on an archipelago during the Jurassic. And with its feathers and bones looking so much like modern flightless island birds, it just makes me wonder,” says Habib.

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