Did Iconic Archaeopteryx Lose Its Ability to Fly?

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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.

Written By: Matt Kaplan and Nature magazine
continue to source article at scientificamerican.com

2 COMMENTS

  1. What, no comments?

    These days, after going back to the Galapagos Finches’ Tale in The Ancestor’s Tale, I am wondering if a lot of the major changes happened extremely quickly, geologically speaking. As a result, I could easily imagine Archaeopteryx being descended from flying ancestors within as little time as 10 million years, and even if Habib’s ideas are partly conjectural, I think he might be on to something. If more fossils of fully flight-capable dinosaurs emerge, dating back to the Mid Jurassic age, then his case could be much stronger.

    I certainly see the logic in what he’s saying. Lots of bird species tend to lose some adaptations for flight when isolated on islands, such as the species that once roamed New Zealand, Madagascar, and Mauritius, and Europe was largely flooded back then, with a few scattered islands in the middle of a tropical sea. Those would be ideal conditions to lose flight, though Archaeopteryx might have retained some ability to climb trees and to glide.

  2. I have heard a similar hypothesis regarding the Dromaeosaurids: that they are not non-avian dinosaurs, but rather avian dinosaurs (birds) that have become large and flightless again. No idea if this is still plausible.

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