title: Shifts in stability and control effectiveness during evolution of Paraves support aerial maneuvering hypotheses for flight origins.
abstract: The capacity for aerial maneuvering was likely a major influence on the evolution of flying animals. Here we evaluate consequences of paravian morphology for aerial performance by quantifying static stability and control effectiveness of physical models for numerous taxa sampled from within the lineage leading to birds (Paraves). Results of aerodynamic testing are mapped phylogenetically to examine how maneuvering characteristics correspond to tail shortening, forewing elaboration, and other morphological features. In the evolution of Paraves we observe shifts from static stability to inherently unstable aerial planforms; control effectiveness also migrated from tails to the forewings. These shifts suggest that a some degree of aerodynamic control and capacity for maneuvering preceded the evolution of a strong power stroke. The timing of shifts also suggests features normally considered in light of development of a power stroke may play important roles in control.
authors.affiliation: Department of Integrative Biology, University of California , Berkeley, CA , USA.
authors.forename: Dennis
authors.initials: D
authors.lastname: Evangelista
authors.affiliation: Department of Integrative Biology, University of California , Berkeley, CA , USA.
authors.forename: Sharlene
authors.initials: S
authors.lastname: Cam
authors.affiliation: Department of Integrative Biology, University of California , Berkeley, CA , USA.
authors.forename: Tony
authors.initials: T
authors.lastname: Huynh
authors.affiliation: Department of Bioengineering, University of California , Berkeley, CA , USA.
authors.forename: Austin
authors.initials: A
authors.lastname: Kwong
authors.affiliation: Department of Bioengineering, University of California , Berkeley, CA , USA.
authors.forename: Homayun
authors.initials: H
authors.lastname: Mehrabani
authors.affiliation: Department of Mechanical Engineering, University of California , Berkeley, CA , USA.
authors.forename: Kyle
authors.initials: K
authors.lastname: Tse
authors.affiliation: Department of Integrative Biology, University of California , Berkeley, CA , USA ; Smithsonian Tropical Research Institute , Balboa , Panama.
authors.forename: Robert
authors.initials: R
authors.lastname: Dudley
keywords: Biomechanics; Control effectiveness; Directed aerial descent; Evolution; Flight; Maneuvering; Paraves; Stability