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Persistent, vertical-migration rhythms in benthic microflora: I. The effect of light and temperature on the rhythmic behaviour of Euglena obtusa1

Published online by Cambridge University Press:  11 May 2009

John D. Palmer
Affiliation:
Department of Biology, New York University, New York, N.Y., 10453
Frank E. Round
Affiliation:
Department of Botany, University of Bristol

Extract

During daytime low tides on the River Avon at Bristol, England, the exposed river banks become a deep green colour owing to the presence of enormous numbers of Euglena obtusa which emerge out of the black mud. Cell densities on the surface surpass 105 cells/cm2. Before the tide returns to cover the area, the cells re-burrow back into the mud and remain there during high tide and throughout the night.

The cells can be prevented from emerging on to the surface mud at low tide by artificially darkening the area with an opaque covering just as the tide recedes. Cells which are already on the surface can be made to re-burrow by similarly placing them in darkness.

The vertical-migration rhythm will persist in the laboratory in constant illumi-nation, constant temperature, and away from the influence of the tide, for nearly one month. In these conditions the rhythm is diurnal, rather than tidal. The rhythm will not persist in constant darkness.

Because of the excessive turbidity of Avon water, each high tide imposes a period of darkness on the surface mud. It is thought that these dark periods transform the fundamental diurnal rhythm into one of tidal frequency.

Various intensities of constant illumination alter the form and amplitude of the rhythm, but not the period. The stable nature of the period, under different light intensities, is thought to be due to a unique, self-stabilizing feature inherent in this type of rhythm.

The rhythm is inhibited at 2° C. Between 5° and 15° C, the period of the rhythm is virtually unaltered; it remains approximately 24 h in length.

Type
Research Article
Copyright
Copyright © Marine Biological Association of the United Kingdom 1965

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References

Aschoff, J., 1960. Exogenous and endogenous components in circadian rhythms. Cold Spring Harb. Symp. quant. Biol., Vol. 25, pp. 1128.CrossRefGoogle ScholarPubMed
Bracher, R., 1919. Observations on Euglena deses. Ann. Bot., Vol. 33, pp. 93108.CrossRefGoogle Scholar
Bracher, R., 1929. The ecology of the Avon banks at Bristol. J. Ecol., Vol. 17, pp. 3581.CrossRefGoogle Scholar
Bracher, R., 1937. The light relation of Euglena limosa Gard. I. The influence of intensity and quality of light on phototaxy. J. Linn. Soc. (Bot.), Vol. 51, pp. 2342.CrossRefGoogle Scholar
Brown, F. A. Jr., 1960. Response to pervasive geophysical factors and the biological clock problem. Cold Spring Harb. Symp. quant. Biol., Vol. 25, pp. 5771.CrossRefGoogle Scholar
Brown, F. A. Jr, Fingerman, M. & Hines, M., 1954. A study of the mechanism involved in shifting of the phases of the endogenous daily rhythm by light stimuli. Biol. Bull. mar. biol. Lab., Woods Hole, Vol. 106, pp. 308–17.CrossRefGoogle Scholar
Bruce, V. G. & Pittendrigh, C. S., 1956. Temperature independence in a unicellular ‘clock’. Proc. natn. Acad. Sci., U.S.A., Vol. 42, pp. 676–82.CrossRefGoogle Scholar
Bühnemann, F., 1955. Das endodiurnal System der Oedogoniumzelle. III. Über den Temperatureinfluss. Z. Naturf., Bd. 10b, pp. 305–10.CrossRefGoogle Scholar
Bünning, E., 1960. Biological clocks. Cold Spring Harb. Symp. quant. Biol., Vol. 25, pp. 19.CrossRefGoogle Scholar
Callame, B. & Debyser, J., 1954. Observations sur les mouvements des diatomées à la surface des sédiments marins de la zone intercotidale. Vie Milieu, T. 5, pp. 242–9.Google Scholar
Hastings, J. W. & Sweeney, B. M., 1957. On the mechanism of temperature independence in a biological clock. Proc. natn. Acad. Sci., U.S.A., Vol. 43, pp. 804–11.CrossRefGoogle Scholar
Mori, S., 1944. Daily rhythmic activity of the sea-pen, Cavernularia obesa Valencinnes. III. Controlling of the activity by light. Zool. Mag., Tokyo, Vol. 56, pp. 81–5.Google Scholar
Palmer, J. D., 1964. Comparative studies in avian persistent rhythms: spontaneous change in period length. Comp. Biochem. Physiol., Vol. 12, pp. 273–82.CrossRefGoogle ScholarPubMed
Perkins, E. J., 1960. The diurnal rhythm of the littoral diatoms of the River Eden estuary, Fife. J. Ecol, Vol. 48, pp. 725–8.CrossRefGoogle Scholar
Pohl, F., 1948. Tagesrhythmus im phototaktischen Verhalten der Euglena gracilis. Z. Naturf., Bd. 3 b, pp. 367–74.CrossRefGoogle Scholar
Pringsheim, E. G., 1956. Contributions toward a monograph of the genus Euglena. Nova Ada Acad. Caesar. Leop. Carol., Vol. 18, pp. 1168.Google Scholar
Sweeney, B. M. & Hastings, J. W., 1958. Rhythmic cell division in populations of Gonyaulax polyedra. J. Protozool., Vol. 5, pp. 217–24.CrossRefGoogle Scholar
Sweeney, B. M. & Hastings, J. W., 1960. Effects of temperature on diurnal rhythms. Cold Spring Harb. Symp. quant. Biol., Vol. 25, pp. 87104.Google Scholar
Taylor, W. R. & Palmer, J. D., 1963. The relationship between light and photo-synthesis in intertidal benthic diatoms. Biol. Bull. mar. biol. Lab., Woods Hole, Vol. 125, pp. 395.Google Scholar
Williams, R. B., 1963. Use of netting to collect motile benthic algae. Limnol. Oceanogr., Vol. 8, pp. 360–1.CrossRefGoogle Scholar