We’ve all seen it: parrots and other exotic birds using their beak to move around. Nothing unusual, right? A bird being a bird. But apparently, it IS a big deal. The interest in this maneuver is the use of the beak as a “limb”, something that becomes odd simply because science says that, to date, no creature – human or otherwise – has an odd number of limbs. With the results of a recent study, the New York Institute of Technology of Osteopathic Medicine (NYITCOM) has come to the realization that our parrots do absolutely use their beak as a “propulsive third limb”.
Before this study, it was just assumed that birds used their beak as a means for stabilization and grasping support while they moved about. They cannot use their wings to grasp and so are dependent on their beaks to do that work for them. But with new studies on locomotive behavior for our feathered pals, it’s determined that the head of a parrot does indeed assist to support, propel, and to power by tripedal locomotion. For this study, six peach-faced lovebirds (also referred to as rosy-faced lovebirds) were used as test subjects. The surprising discovery was that the birds do employ their beaks as a third limb generating the same force of power that a human or primate forearm would generate in climbing and pulling themselves up. This would give truth to the reality that a parrot’s neck is incredibly strong and is biomechanically designed to be a third limb.
To actualize this study, two separate tests were performed with the six lovebirds. They were free of any malformations that might have encouraged the bird to adapt, to acquire useable data. High-speed cameras were mounted, and flat runways were constructed. The runways were designed to rotate to create several angles of ascent (0.0֯, 22.5֯, 45.0֯, 67.5֯, 90.0֯). As the birds were video-captured running at their own speed across the rotating runway, repeated data was rich enough to extract regarding the use of beak, tail, and wing during the experiment. Other more complex testing was undertaken as well to balance the study and to help solidify the results.
In the initial run experiments, it was easy to see that the parrots began to use their beaks at the 45֯ angle. By the 90֯ angle, the parrots’ beaks were generating the previously mentioned forces of a limb. It was also determined that the birds’ tails produced minimal forces to help the parrot ascend. One of the assumptions pulled from this set of experiments shows that the parrots have likely evolved over time to help them develop these unique climbing forces. As a study conclusion, it is realized that parrots are the only birds known to use the head as a third limb. And the only creature known to do so…period.
This rare locomotive study on parrots will continue for several more years to try to understand how this unusual propulsive behavior is undertaken by the parrots on a muscular and anatomical level.
The new study was published May 18 in the prestigious journal of Proceedings of The Royal Society B: Biological Sciences. The quest was studied and written up by Melody W. Young, Edward Dickinson, Nicholas D. Flaim, and by Michael Granatosky, a Ph.D, who is an assistant Professor of Anatomy. If you wish to delve in deeper than this article allows, follow this link for the published study.