Walking Like Dinosaurs: Chickens with Artificial Tails Provide Clues about Non-Avian Theropod Locomotion-Robel Bekele

posted Aug 18, 2016, 9:25 PM by Robel Bekele
Because of multiple pieces of evidence, scientists widely accept the fact that birds evolved from bipedal theropod dinosaurs. Birds have inherited many locomotory traits from these dinosaurs: which include bipedalism, fully erect posture, and parasagittal hind limb movement. There are some traits that the two species don't share, like the center of mass that has been moved through the evolutionary shift from the posterior area to a more anterior location. Two scientists named Carrano and Biewener wanted to see whether or no the center of mass affected postural and kinetic changes in birds so they attached artificial tails to chickens to recreate dinosaur-like limb posture and locomotion in chickens. The people who wrote this article wanted to continue Carrano and Biewener's research. They raised twelve chickens and put them into three groups: the control, control-weight, and experimental groups. The attached a coat with a lead weight and put it on the chickens in the control-weight group and attached artificial tails to the chickens in the experimental group. The control group was left alone. They recorded the three groups of chickens while they were standing  without moving for at least 10 seconds and while they moved 3 ms encouraged by food. The knee and ankle joints of the chickens in the experimental group were more extended than in the control group and the femur was more extruded in the beginning of the stance phase and more retracted in the end of the stance phase than in the control group.       

Bruno Grossi, Omar Larach, Mauricio Canals, Rodrigo A. Vasquez. "Walking Like Dinosaurs: Chickens with Artificial Tails Provide Clues about Non-Avian Theropod Locomotion." PLOS February 5, 2014. August 18, 2016.