|
|
|
|||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
EFFECTS OF OPERATING FREQUENCY AND TEMPERATURE ON MECHANICAL POWER OUTPUT FROM MOTH FLIGHT MUSCLE
1 Department of Psychobiology, University of California, Irvine, CA 92717, USA; Present address: Department of Biology, UMass/Boston, Boston, MA 02125-3393, USA
2 Department of Psychobiology, University of California, Irvine, CA 92717, USA
1. Mechanical work output was determined for an indirect flight muscle, the first dorsoventral, of the tobacco hawkmoth Manduca sexta. Work output per cycle was calculated from the area of force-position loops obtained during phasic electrical stimulation (1 stimulus cycle-1) and imposed sinusoidal length change. There was an optimal stimulus phase and an optimal length change (strain) that maximized work output (loop area) at constant cycle frequency and temperature.
2. When cycle frequency was increased at constant temperature, work output first increased and then decreased. It was always possible to find a frequency that maximized work output. There also always existed a higher frequency (termed the optimal frequency in this paper) that maximized the mechanical power output, which is the product of the cycle frequency (s-1) and the work per cycle (J).
3. As temperature increased from 20 to 40°C, the mean maximum power output increased from about 20 to about 90 W kg-1 of muscle (Q10=2.09). There was a corresponding increase in optimal frequency from 12.7 to 28.3 Hz, in the work per cycle at optimal frequency from 1.6 to 3.2Jkg-1 muscle and in mean optimal strain from 5.9 to 7.9%.
4. Two electrical stimuli per cycle cannot increase power output at flight frequencies, but if frequency is reduced then power output can be increased with multiple stimulation.
5. Comparison of mechanical power output from muscle and published values of energy expenditure during free hovering flight of Manduca suggests that mechanical efficiency is about 10%.
6. In the tobacco hawkmoth there is a good correspondence between, on the one hand, the conditions of temperature (35–40°C) and cycle frequency (28–32 Hz) that produce maximal mechanical power output in the muscle preparation and, on the other hand, the thoracic temperature (35–42°C) and wing beat frequency (24–32 Hz) observed during hovering flight.
Key words: work, mechanical power, synchronous muscle, insect muscle, muscle efficiency, cycle frequency, temperature, flight, hawkmoth, Manduca sexta
Accepted on October 19, 1989
This article has been cited by other articles:
![]() |
E. A. Jones, A. S. Jong, and D. J. Ellerby The effects of acute temperature change on swimming performance in bluegill sunfish Lepomis macrochirus J. Exp. Biol., May 1, 2008; 211(9): 1386 - 1393. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. A. Woods Jr, S. J. Fusillo, and B. A. Trimmer Dynamic properties of a locomotory muscle of the tobacco hornworm Manduca sexta during strain cycling and simulated natural crawling J. Exp. Biol., March 15, 2008; 211(6): 873 - 882. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. J. Ellerby and G. N. Askew Modulation of flight muscle power output in budgerigars Melopsittacus undulatus and zebra finches Taeniopygia guttata: in vitro muscle performance J. Exp. Biol., November 1, 2007; 210(21): 3780 - 3788. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Guschlbauer, H. Scharstein, and A. Buschges The extensor tibiae muscle of the stick insect: biomechanical properties of an insect walking leg muscle J. Exp. Biol., March 15, 2007; 210(6): 1092 - 1108. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. S. Tu and T. L. Daniel Submaximal power output from the dorsolongitudinal flight muscles of the hawkmoth Manduca sexta J. Exp. Biol., December 15, 2004; 207(26): 4651 - 4662. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Fischer, H. Wolf, and A. Buschges The locust tegula: kinematic parameters and activity pattern during the wing stroke J. Exp. Biol., June 1, 2002; 205(11): 1531 - 1545. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. H. Marden, G. H. Fitzhugh, M. Girgenrath, M. R. Wolf, and S. Girgenrath Alternative splicing, muscle contraction and intraspecific variation: associations between troponin T transcripts, Ca2+ sensitivity and the force and power output of dragonfly flight muscles during oscillatory contraction J. Exp. Biol., March 12, 2002; 204(20): 3457 - 3470. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. A. Syme and R. E. Shadwick Effects of longitudinal body position and swimming speed on mechanical power of deep red muscle from skipjack tuna (Katsuwonus pelamis) J. Exp. Biol., January 15, 2002; 205(2): 189 - 200. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. K. Josephson, J. G. Malamud, and D. R. Stokes The efficiency of an asynchronous flight muscle from a beetle J. Exp. Biol., January 12, 2001; 204(23): 4125 - 4139. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. N. Askew, R. L. Marsh, and C. P. Ellington The mechanical power output of the flight muscles of blue-breasted quail (Coturnix chinensis) during take-off J. Exp. Biol., January 11, 2001; 204(21): 3601 - 3619. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Josephson, J. Malamud, and D. Stokes Power output by an asynchronous flight muscle from a beetle J. Exp. Biol., January 9, 2000; 203(17): 2667 - 2689. [Abstract] [PDF] |
||||
![]() |
V. Brezina and K. R. Weiss The Neuromuscular Transform Constrains the Production of Functional Rhythmic Behaviors J Neurophysiol, January 1, 2000; 83(1): 232 - 259. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Rome, D. Swank, and D. Coughlin The influence of temperature on power production during swimming. II. Mechanics of red muscle fibres in vivo J. Exp. Biol., January 1, 2000; 203(2): 333 - 345. [Abstract] [PDF] |
||||
![]() |
M Girgenrath and R. Marsh Power output of sound-producing muscles in the tree frogs Hyla versicolor and Hyla chrysoscelis J. Exp. Biol., January 11, 1999; 202(22): 3225 - 3237. [Abstract] [PDF] |
||||