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Rivoli's Hummingbird: Eugenes Fulgens, Donald R. Powers

Faculty Publications - Department of Biological & Molecular Science

Rivoli's Hummingbird was named in honor of the Duke of Rivoli when the species was described by René Lesson in 1829. Even when it became known that William Swainson had written an earlier description of this species in 1827, the common name Rivoli's Hummingbird remained until the early 1980s, when it was changed to Magnificent Hummingbird. In 2017, however, the name was restored to Rivoli's Hummingbird when the American Ornithological Society officially recognized Eugenes fulgens as a distinct species from E. spectabilis, the Talamanca Hummingbird, of the highlands of Costa Rica and western Panama.

Rivoli's Hummingbird is found from the …

Integrating Morphology And Kinematics In The Scaling Of Hummingbird Hovering Metabolic Rate And Efficiency, Derrick J. E. Groom, M. Cecilia B. Toledo, Donald R. Powers, Bret W. Tobalske, Kenneth C. Welch Jr.

Faculty Publications - Department of Biological & Molecular Science

Wing kinematics and morphology are influential upon the aerodynamics of flight. However, there is a lack of studies linking these variables to metabolic costs, particularly in the context of morphological adaptation to body size. Furthermore, the conversion efficiency from chemical energy into movement by the muscles (mechanochemical efficiency) scales with mass in terrestrial quadrupeds, but this scaling relationship has not been demonstrated within flying vertebrates. Positive scaling of efficiency with body size may reduce the metabolic costs of flight for relatively larger species. Here, we assembled a dataset of morphological, kinematic, and metabolic data on hovering hummingbirds to explore the …

Hovering In The Heat: Effects Of Environmental Temperature On Heat Regulation In Foraging Hummingbirds, Don R. Powers, Kathleen M. Langland, Susan M. Wethington, Sean D. Powers, Catherine H. Graham, Bret W. Tobalske

Faculty Publications - Department of Biological & Molecular Science

At high temperature (greater than 40°C) endotherms experience reduced passive heat dissipation (radiation, conduction and convection) and increased reliance on evaporative heat loss. High temperatures challenge flying birds due to heat produced by wing muscles. Hummingbirds depend on flight for foraging, yet inhabit hot regions. We used infrared thermography to explore how lower passive heat dissipation during flight impacts body-heat management in broad-billed (Cynanthus latirostris, 3.0 g), black-chinned (Archilochus alexandri, 3.0 g), Rivoli’s (Eugenes fulgens, 7.5 g) and blue-throated (Lampornis clemenciae, 8.0 g) hummingbirds in southeastern Arizona and calliope hummingbirds (Selasphorus calliope, 2.6 g) in Montana. Thermal gradients driving passive …

Flight Mechanics And Control Of Escape Manoeuvres In Hummingbirds. I. Flight Kinematics, Bo Cheng, Bret W. Tobalske, Donald R. Powers, Tyson L. Hedrick, Susan M. Wethington, George T.C. Chiu, Xinyan Deng

Faculty Publications - Department of Biological & Molecular Science

Hummingbirds are nature’s masters of aerobatic manoeuvres. Previous research shows that hummingbirds and insects converged evolutionarily upon similar aerodynamic mechanisms and kinematics in hovering. Herein, we use three-dimensional kinematic data to begin to test for similar convergence of kinematics used for escape flight and to explore the effects of body size upon manoeuvring. We studied four hummingbird species in North America including two large species (magnificent hummingbird, Eugenes fulgens, 7.8 g, and blue-throated hummingbird, Lampornis clemenciae, 8.0 g) and two smaller species (broad-billed hummingbird, Cynanthus latirostris, 3.4 g, and black-chinned hummingbirds Archilochus alexandri, 3.1 g). Starting from a steady hover, …

Flight Mechanics And Control Of Escape Manoeuvres In Hummingbirds. Ii. Aerodynamic Force Production, Flight Control And Performance Limitations, Bo Cheng, Bret W. Tobalske, Donald R. Powers, Tyson L. Hedrick, Yi Wang, Susan M. Wethington, George T.C. Chiu, Xinyan Deng

Faculty Publications - Department of Biological & Molecular Science

The superior manoeuvrability of hummingbirds emerges from complex interactions of specialized neural and physiological processes with the unique flight dynamics of flapping wings. Escape manoeuvring is an ecologically relevant, natural behaviour of hummingbirds, from which we can gain understanding into the functional limits of vertebrate locomotor capacity. Here, we extend our kinematic analysis of escape manoeuvres from a companion paper to assess two potential limiting factors of the manoeuvring performance of hummingbirds: (1) muscle mechanical power output and (2) delays in the neural sensing and control system. We focused on the magnificent hummingbird (Eugenes fulgens, 7.8 g) and the black-chinned …

The Impact Of Social Interactions On Torpor Use In Hummingbirds, Donald R. Powers

Faculty Publications - Department of Biological & Molecular Science

Measurements of metabolic rate and fat deposition were made on a three-species hummingbird guild in southeastern Arizona to determine if the energetic advantage gained by a dominant territorial species (Lampornis clemenciae) over subordinate competitors (Archilochus alexandri and Eugenes fulgens) resulted in less frequent use of torpor. Results showed that L. clemenciae was able to store enough fat during the day to avoid nocturnal torpor. Restricted access to food limited fat storage in both competitors, resulting in frequent torpor use. Avoidance of torpor by L. clemenciae supports the notion that use of nocturnal torpor by hummingbirds comes with a cost, and …