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Rapid shell closure in the brachiopods Terebratulina retusa and Terebrataua transversa

Published online by Cambridge University Press:  11 May 2009

Spafford C. Ackerly
Affiliation:
Department of Geological Sciences, Cornell University, Ithaca, New York 14853, USA

Extract

Rapid shell closure in articulate brachiopods, occurring by a twitch contraction of the the ‘quick’ adductor muscles, is a response to disturbance or to physiological requirements of the organism. The relative simplicity of the closing system permits a detailed analysis of the functional architecture of the mechanism and the underlying principles of skeleto-muscular organization, in terms of (1) basic kinematic properties of the system (speeds and times of closure), (2) hydrodynamic reactions resisting closure, and (3) considerations of muscle physiology and mechanics.

Analyses of shell closure in the brachiopods Terebratulina retusa from the Firth of Lorn, Scotland, and Terebratalia transversa from Puget Sound, USA, reveal (1) shell-closing times of the order of 50 to 70 ms, (2) closing velocities of the order of 3·5 radians s-1, from initial gapes of about 0·05 to 0·2 rad, and (3) muscle moment forces and hydrodynamic reactions with magnitudes of the order of 5 × 10-4 N m (5 g cm). Muscle tensions developed in the ‘quick’ adductor muscle are of the order of 105 N m2, and contraction velocities are of the order of one muscle length per second. Hydrodynamic reactions are a fundamental constraint on the closing mechanism, as determined by the concordance of actual closing events with predictions of a hydrodynamic model.

Type
Research Article
Copyright
Copyright © Marine Biological Association of the United Kingdom 1992

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References

Ackerly, S.C., 1985a. Hinge mechanism in the Orthida and Strophomenida (Brachiopoda): a quantitative assessment. Geological Society of America, Abstracts with Programs, 17, 1.Google Scholar
Ackerly, S.C., 1985b. Allometry and muscle mechanics in orthid brachiopods. In Proceedings of the First International Congress on Brachiopods, Universite de Bretagne Occidentale, Brest, France, 913 September, 1985, p. 1.Google Scholar
Ackerly, S.C., 1991a. Rapid shell closure in Recent Terebratulida and Paleozoic Orthida. In Brachiopods through time (ed. D.I., Mackinnonet al.), pp. 177182. Rotterdam: A.A. Balkema.Google Scholar
Ackerly, S.C., 1991b. Hydrodynamics of rapid shell closure in articulate brachiopods. journal of Experimental Biology, 156, 287314.CrossRefGoogle Scholar
Armstrong, J., 1968. Analysis of the function of the diductor muscles in articulate brachiopods. Neues Jahrbuch fur Geologie und Paläontologie, Monatshefte, 1968, 641654.Google Scholar
Borgerding, J.L., 1976. Evolution of the diductor muscle system in articulate brachiopods with respect to mechanical efficiency of hingement. MS thesis, University of Indiana.Google Scholar
Carlson, S.J., 1984. Evolutionary trends in brachiopod hinge mechanics. Geological Society of America, Abstracts with Programs, 16, 463.Google Scholar
Carlson, S.J., 1986. Ontogenetic and evolutionary trends in the articulate brachiopod hinge mechanism. PhD thesis, University of Michigan.Google Scholar
Collins, M.J., 1986. Taphonomic processes in a deep water Modiolus-brachiopod assemblage from the west coast of Scotland. PhD thesis, University of Glasgow.Google Scholar
Cox, I., 1934. Notes on the shell musculature of Gryphus vitreus (Born). Geological Magazine, 71, 226230.CrossRefGoogle Scholar
Curry, G.B., 1979. Shell growth and ecology of Recent brachiopods from Scotland and New Zealand. PhD thesis, University of London.Google Scholar
Curry, G.B., 1982. Ecology and population structure of the Recent brachiopod Terebratulina from Scotland. Palaeontology, 25, 227246.Google Scholar
Eshleman, W.P. & Wilkens, J.L., 1979. Actomyosin ATPase activities in the brachiopod Terebratalia transversa. Canadian journal of Zoology, 57, 19441949.CrossRefGoogle Scholar
Goldspink, G., 1977. Design of muscles in relation to locomotion. In Mechanics and energetics of animal locomotion (ed. Alexander, R. McN. and G., Goldspink), pp. 122. London: Chapman and Hall.Google Scholar
Gould, S.J., 1977. Ontogeny and phylogeny. Cambridge, Massachusetts: Harvard University Press.Google Scholar
Hill, A.V., 1950. The dimensions of animals and their muscular dynamics. Science Progress. London, 38, 209230.Google Scholar
Hughes, W.W., Rosenberg, G.D., & Tkachuck, R.D., 1988. Growth increments in the shell of the living brachiopod Terebratalia transversa. Marine Biology, 98, 511518.CrossRefGoogle Scholar
Jaanusson, V., 1971. Evolution of the brachiopod hinge. Smithsonian Contributions to Paleobiology, 3, 3346.Google Scholar
Jaanusson, V. & Neuhaus, H., 1965. Mechanism of the diductor muscles in articulate brachiopods. Stockholm Contributions in Geology, 13, 18.Google Scholar
Labarbera, M., 1978. Brachiopod orientation to water movement: functional morphology. Lethaia, 11, 6779.CrossRefGoogle Scholar
Mackinnon, D.I., 1977. The formation of muscle scars in articulate brachiopods. Philosophical Transactions of the Royal Society of London (B), 280, 127.Google Scholar
McCammon, H.M., 1971. Behavior in the brachiopod Terebratulina septentrionalis (Couthouy). Journal of Experimental Marine Biology and Ecology, 6, 3545.CrossRefGoogle Scholar
Richardson, J.R., 1981. Brachiopods and pedicles. Paleobiology, 7, 8795.CrossRefGoogle Scholar
Rudwick, M.J.S., 1961. ‘Quick’ and ‘catch’ adductor muscles in brachiopods. Nature, London, 191, 1021.CrossRefGoogle Scholar
Rudwick, M.J.S., 1962. Filter-feeding mechanisms in some brachiopods from New Zealand. Journal of the Linnean Society of London. Zoology, 44, 592615.CrossRefGoogle Scholar
Rudwick, M.J.S., 1970. Living and Fossil Brachiopods. London: Hutchinson.Google Scholar
Thayer, C.W., 1975. Diductor muscles of brachiopods: active or passive? Paleobiology, 1, 4447.CrossRefGoogle Scholar
Thayer, C.W., 1977. Recruitment, growth, and mortality of a living articulate brachiopod, with implications for the interpretation of survivorship curves. Paleobiology, 3, 98109.CrossRefGoogle Scholar
Wilkens, J.L., 1978a. Adductor muscles of brachiopods: activation and contraction. Canadian Journal of Zoology, 56, 315323.Google Scholar
Wilkens, J.L., 1978b. Diductor muscles of brachiopods: activation and very slow contraction. Canadian Journal of Zoology, 56, 324332.CrossRefGoogle Scholar