QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Dudley, R. Search for Related Content PubMed PubMed Citation Articles by Dudley, R.

Journal of Experimental Biology, Vol 198, Issue 4 1065-1070, Copyright © 1995 by Company of Biologists

JOURNAL ARTICLES

Extraordinary flight performance of orchid bees (Apidae: Euglossini) hovering in heliox (80% He/20% O2)

R Dudley

Limits to insect flight performance are difficult to evaluate because the full range of aerodynamic capabilities cannot be easily elicited or controlled. Invasive experimental manipulations, such as tethering and weight addition, may adversely affect the biomechanics of the flight system as a whole. Because air density is a major determinant of aerodynamic force production, gas mixtures of variable density can be used to investigate insect flight performance non-invasively. Three species of orchid bee hovering in heliox (80 % He/20 % O2) exhibited dramatic increases in lift and power output relative to flight in normal air. Stroke amplitude increased significantly in heliox, while wingbeat frequency was unchanged; the Reynolds numbers of the wings decreased on average by 41 %. Although lift performance of airfoils generally degrades at lower Reynolds numbers, mean lift coefficients in heliox increased significantly relative to values for hovering in normal air. Mean muscle mass-specific power output for flight in heliox mixtures ranged from 130 to 160 W kg-1, substantially exceeding values determined from isolated asynchronous muscle preparations as well as limits postulated from the results of load-lifting experiments. The use of variable-density gas mixtures to examine animal flight performance is a simple yet powerful manipulation that will permit a new evaluation of both insect and vertebrate flight mechanics.

This article has been cited by other articles:

				R. Dudley and Y. Winter Hovering flight mechanics of neotropical flower bats (Phyllostomidae: Glossophaginae) in normodense and hypodense gas mixtures J. Exp. Biol., December 1, 2002; 205(23): 3669 - 3677. [Abstract] [Full Text] [PDF]

				J. R. Usherwood and C. P. Ellington The aerodynamics of revolving wings II. Propeller force coefficients from mayfly to quail J. Exp. Biol., June 1, 2002; 205(11): 1565 - 1576. [Abstract] [Full Text] [PDF]

				D. L. Altshuler, P. Chai, and J. S. P. Chen Hovering Performance of Hummingbirds in Hyperoxic Gas Mixtures J. Exp. Biol., January 6, 2001; 204(11): 2021 - 2027. [Abstract] [Full Text] [PDF]

				F. Lehmann and M. Dickinson The production of elevated flight force compromises manoeuvrability in the fruit fly Drosophila melanogaster J. Exp. Biol., January 2, 2001; 204(4): 627 - 635. [Abstract] [PDF]

				R. Suarez, J. Staples, J. Lighton, and O Mathieu-Costello Mitochondrial function in flying honeybees (Apis mellifera): respiratory chain enzymes and electron flow from complex III to oxygen J. Exp. Biol., January 3, 2000; 203(5): 905 - 911. [Abstract] [PDF]

				C. Ellington The novel aerodynamics of insect flight: applications to micro-air vehicles J. Exp. Biol., January 12, 1999; 202(23): 3439 - 3448. [Abstract] [PDF]