Kinematics and Center of Mass Mechanics During Terrestrial Locomotion in Northern Lapwings (Vanellus vanellus, Charadriiformes)
Version of Record online: 27 AUG 2012
Copyright © 2012 Wiley Periodicals, Inc.
Journal of Experimental Zoology Part A: Ecological Genetics and Physiology
Volume 317, Issue 9, pages 580–594, November 2012
How to Cite
2012. Kinematics and center of mass mechanics during terrestrial locomotion in northern lapwings (Vanellus vanellus, Charadriiformes). J. Exp. Zool. 317A:580–594., , , , .
- Issue online: 10 OCT 2012
- Version of Record online: 27 AUG 2012
- Manuscript Accepted: 10 JUL 2012
- Manuscript Revised: 2 JUL 2012
- Manuscript Received: 15 MAY 2012
- German Research Council (DFG). Grant Numbers: Fi 410/15–1, Bl 236/22–1
Avian bipedalism is best studied in derived walking/running specialists. Here, we use kinematics and center of mass (CoM) mechanical energy patterns to investigate gait transitions of lapwings—migratory birds that forage on the ground, and therefore may need a trade-off between the functional demands of terrestrial locomotion and long distance flights. The animals ran on a treadmill while high-speed X-ray videos were recorded within the sustainable speed range. Instantaneous CoM mechanics were computed from integrating kinematics and body segment properties. Lapwings exhibit similar locomotor characteristics to specialized walking/running birds, but have less distinct gaits. At slow speeds no clear separation between vaulting (i.e., walking) and bouncing (i.e., running) energy patterns exists. Mechanical energy recovery of non-bouncing gaits correlates poorly with speed and suggests inefficient use of the inverted pendulum mechanism. Speed ranges of gaits overlap considerably, especially those of grounded running, a gait with CoM mechanics indicative of running but without an aerial phase, and aerial phase running, with no preferential gait at most speeds. Compliant limb morphology and grounded running in birds can be regarded as an evolutionary constraint, but lapwings effectively make use of advantages offered by this gait for a great fraction of their speed range. Thus, effective usage of grounded running during terrestrial locomotion is suggested generally to be a part of striding avian bipedalism—even in species not specialized in walking/running locomotion. J. Exp. Zool. 317A:580–594, 2012. © 2012 Wiley Periodicals, Inc.