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 Westneat, M. Articles by Walker, J. Search for Related Content PubMed PubMed Citation Articles by Westneat, M. Articles by Walker, J. Social Bookmarking                         What's this?

Journal of Experimental Biology, Vol 200, Issue 13 1881-1893, Copyright © 1997 by Company of Biologists

JOURNAL ARTICLES

Motor patterns of labriform locomotion: kinematic and electromyographic analysis of pectoral fin swimming in the labrid fish Gomphosus varius

M Westneat and J Walker

Labriform locomotion is a widespread swimming mechanism in fishes during which propulsive forces are generated by oscillating the pectoral fins. We examined the activity of the six major muscles that power the pectoral fin of the bird wrasse Gomphosus varius (Labridae: Perciformes). The muscles studied included the fin abductors (arrector ventralis, abductor superficialis and abductor profundus) and the fin adductors (arrector dorsalis, adductor superficialis and adductor profundus). Our goals were to determine the pattern of muscle activity that drives the fins in abduction and adduction cycles during pectoral fin locomotion, to examine changes in the timing and amplitude of electromyographic (EMG) patterns with increases in swimming speed and to correlate EMG patterns with the kinematics of pectoral fin propulsion. EMG data were recorded from three individuals over a range of swimming speeds from 15 to 70 cm s-1 (1­4.8 TL s-1, where TL is total body length). The basic motor pattern of pectoral propulsion is alternating activity of the antagonist abductor and adductor groups. The downstroke is characterized by activity of the arrector ventralis muscle before the other abductors, whereas the upstroke involves nearly synchronous activity of the three adductors. Most EMG variables (duration, onset time, amplitude and integrated area) showed significant correlations with swimming speeds. However, the timing and duration of muscle activity are relatively constant across speeds when expressed as a fraction of the stride period, which decreases with increased velocity. Synchronous recordings of kinematic data (maximal abduction and adduction) with EMG data revealed that activity in the abductors began after maximal adduction and that activity in the adductors began nearly synchronously with maximal abduction. Thus, the pectoral fin mechanism of G. varius is activated by positive work from both abductor and adductor muscle groups over most of the range of swimming speeds. The adductors produce some negative work only at the highest swimming velocities. We combine information from pectoral fin morphology, swimming kinematics and motor patterns to interpret the musculoskeletal mechanism of pectoral propulsion in labrid fishes.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				E. M. Standen Pelvic fin locomotor function in fishes: three-dimensional kinematics in rainbow trout (Oncorhynchus mykiss) J. Exp. Biol., September 15, 2008; 211(18): 2931 - 2942. [Abstract] [Full Text] [PDF]

				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]

				J. L. Kendall, K. S. Lucey, E. A. Jones, J. Wang, and D. J. Ellerby Mechanical and energetic factors underlying gait transitions in bluegill sunfish (Lepomis macrochirus) J. Exp. Biol., December 15, 2007; 210(24): 4265 - 4271. [Abstract] [Full Text] [PDF]

				E. A. Jones, K. S. Lucey, and D. J. Ellerby Efficiency of labriform swimming in the bluegill sunfish (Lepomis macrochirus) J. Exp. Biol., October 1, 2007; 210(19): 3422 - 3429. [Abstract] [Full Text] [PDF]

				A. N. Rice and M. W. Westneat Coordination of feeding, locomotor and visual systems in parrotfishes (Teleostei: Labridae) J. Exp. Biol., September 15, 2005; 208(18): 3503 - 3518. [Abstract] [Full Text] [PDF]

				J. A. Walker Dynamics of pectoral fin rowing in a fish with an extreme rowing stroke: the threespine stickleback (Gasterosteus aculeatus) J. Exp. Biol., May 1, 2004; 207(11): 1925 - 1939. [Abstract] [Full Text] [PDF]

				E. G. Drucker and G. V. Lauder Wake Dynamics and Locomotor Function in Fishes: Interpreting Evolutionary Patterns in Pectoral Fin Design Integr. Comp. Biol., November 1, 2002; 42(5): 997 - 1008. [Abstract] [Full Text] [PDF]

				K. E. Korsmeyer, J. F. Steffensen, and J. Herskin Energetics of median and paired fin swimming, body and caudal fin swimming, and gait transition in parrotfish (Scarus schlegeli) and triggerfish (Rhinecanthus aculeatus) J. Exp. Biol., May 1, 2002; 205(9): 1253 - 1263. [Abstract] [Full Text] [PDF]

				E. G. Drucker and G. V. Lauder Experimental Hydrodynamics of Fish Locomotion: Functional Insights from Wake Visualization Integr. Comp. Biol., April 1, 2002; 42(2): 243 - 257. [Abstract] [Full Text] [PDF]

				L. Rosenberger and M. Westneat Functional morphology of undulatory pectoral fin locomotion in the stingray taeniura lymma (Chondrichthyes: dasyatidae) J. Exp. Biol., January 12, 1999; 202(24): 3523 - 3539. [Abstract] [PDF]

				C. Wilga and G. Lauder Locomotion in sturgeon: function of the pectoral fins J. Exp. Biol., January 9, 1999; 202(18): 2413 - 2432. [Abstract] [PDF]