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Density-dependent sex ratio in Echinomermella matsi (Nematoda), a parasite of the sea urchin Strongylocentrotus droebachiensis

Published online by Cambridge University Press:  06 April 2009

A. Stien ,
O. Halvorsen  and
H. P. Leinaas
A. Stien
Affiliation:
Zoological Museum, University of Oslo, Sarsgt. 1, 0562 Oslo, Norway
O. Halvorsen
Affiliation:
Zoological Museum, University of Oslo, Sarsgt. 1, 0562 Oslo, Norway
H. P. Leinaas
Affiliation:
Norwegian Institute for Nature Research, PO Box 1037, Blindern, 0315 Oslo, Norway
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Summary

We investigated the adult sex ratio in 70 infrapopulations of the nematode Echinomermella matsi, a parasite of the green sea urchin Strongylocentrotus droebachiensis. The adult sex ratio was skewed towards female dominance at low adult intensity and towards male dominance at high adult intensity. We hypothesize that this is due to differences between the sexes in development and mortality rates, or that female recruitment is density dependent. A model with differences between the sexes in developmental and mortality rates may develop the observed sex ratios if the female developmental and mortality rates are several times that of the males. A large difference in developmental rates between the sexes appears unreasonable because the developmental rate for both sexes is low, and the predicted low female life-expectancy is unlikely because the males appear to accumulate in infrapopulations as the females age. Density dependence of female numbers is, however, supported by a significantly lower female recruitment in infrapopulations with old females. We also find that the mean male length is negatively related to measures of crowding, thereby supporting the hypothesis that competition is of importance in E. matsi infrapopulations. A female bias at low intensities of infection, a density dependence in female recruitment and the taxonomic position of E. matsi indicate that sex may be environmentally determined in this nematode.

Keywords

Echinomermella matsiStrongylocentrotus droebachiensissex ratioenvironmental sex determination.
Type
Research Article
Information
Parasitology , Volume 112 , Issue 1 , January 1996 , pp. 105 - 112
Copyright
Copyright © Cambridge University Press 1996

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References

REFERENCES

Adams, J., Greenwood, P. & Naylor, C. (1987). Evolutionary aspects of environmental sex determination. International Journal of Invertebrate Reproduction and Development 11, 123–36.CrossRefGoogle Scholar
Adamson, M. L. (1989). Evolutionary biology of the Oxyurida (Nematoda): biofacies of a haplodiploid taxon. Advances in Parasitology 28, 175–228.CrossRefGoogle ScholarPubMed
Allen, G. A. & Antos, J. A. (1993). Sex ratio variation in the dioecious shrub Oemleria cerasiformis. American Naturalist 141, 537–53.CrossRefGoogle ScholarPubMed
Anonymous (1988). Digitizing Software a Rockworks Application. Colorado: Rockware.Google Scholar
Anonymous (1992). Miljørapport (in Norwegian). Fisken og Havet Særnummer 2.Google Scholar
Berland, B. (1984). Basic techniques involved in helminth preservation. Systematic Parasitology 6, 242–5.CrossRefGoogle Scholar
Bull, J. J. & Charnov, E. L. (1988). How fundamental are Fisherian sex ratios? Oxford Surveys in Evolutionary Biology 5, 96–135.Google Scholar
Charnov, E. L. & Bull, J. J. (1977). When is sex environmentally determined? Nature, London 266, 828–30.CrossRefGoogle ScholarPubMed
Charnov, E. L. & Bull, J. J. (1989). Non-fisherian sex ratios with sex change and environmental sex determination. Nature, London 338, 148–50.CrossRefGoogle Scholar
ChitWood, B. G. (1933). The systematic position of Echinonema grayi Gemmil, 1901. Journal of Parasitology 20, 104.Google Scholar
Chitwood, B. G. & Chitwood, M. B. (1974). Introduction to Nematology. Baltimore: University Park Press.Google Scholar
Christie, J. R. (1929). Some observations on sex in the Mermithidae. Journal of Experimental Zoology 53, 59–76.CrossRefGoogle Scholar
Clark, W. C. (1978). Metabolite-mediated density-dependent sex determination in a free-living nematode, Diplenteron potohikus. Journal of Zoology 184, 245–54.CrossRefGoogle Scholar
Coil, W. H. (1963). The life cycle of a diecious tapeworm, Gyrocoelia pagollae Cable and Mayers, 1956. Journal of Parasitology 49 (Suppl.), 38–9.Google Scholar
Crofton, H. D. & Whitlock, J. H. (1969). Changes in sex ratio in Haemonchus contortus cayugensis. Cornell Veterinarian 57, 388–92.Google Scholar
Goodman, L. A. (1977). Population growth of the sexes. In Mathematical Demography (ed. Smith, D. & Kayfitz, N.), PP. 469–80. New York: Springer-Verlag.CrossRefGoogle Scholar
Gordon, R., Squires, J. M., Babie, S. J. & Burford, I. R. (1981). Effects of host diet on Romanomermis culicivorax, a mermithid parasite of mosquitoes. Journal of Nematology 13, 285–90.Google ScholarPubMed
Hagen, N. T. (1987). Sea urchin outbreaks and nematode epizootics in Vestfjorden, northern Norway. Sarsia 72, 213–29.CrossRefGoogle Scholar
Hagen, N. T. (1992). Macroparasitic epizootic disease: a potential mechanism for the termination of sea urchin outbreaks in Northern Norway. Marine Biology 114, 469–78.CrossRefGoogle Scholar
Johnson, R. N. & Viglierchio, D. R. (1969). Sugar beet nematode (Heterodera schachtii) reared on axenic Beta vulgaris root explants. II. Selected environmental and nutritional factors affecting development and sex ratio. Nematodologica 15, 144–52.CrossRefGoogle Scholar
Kendall, D. G. (1977). Stochastic processes and population growth. In Mathematical Demography (ed. Smith, D. & Kayfitz, N.), PP. 465–8. New York,: Springer-Verlag.CrossRefGoogle Scholar
Koliopanos, C. N. & Triantaphyllou, A. C. (1972).Effect of infection density on sex ratio of Heterodera glycines. Nematodologica 18, 131–7.CrossRefGoogle Scholar
Korpelainen, H. (1990). Sex ratios and conditions required for environmental sex determination in animals. Biological Reviews 65, 147–84.CrossRefGoogle ScholarPubMed
Manly, B. F. J. (1991). Randomization and Monte Carlo Methods in Biology. London: Chapman and Hall.CrossRefGoogle Scholar
Margolis, L., Esch, G. W., Holmes, J. C., Kuris, A. M. & Schad, G. A. (1982). The use of ecological terms in parasitology (report of an ad hoc committee of the American Society of Parasitologists). Journal of Parasitology 68, 131–3.CrossRefGoogle Scholar
Meagher, T. R. (1981). Population biology of Chamaelirium luteum, a dioecious lily. II. Mechanisms governing sex ratios. Evolution 35, 557–67.Google ScholarPubMed
Parenti, U. (1965). Male and female influence of adult individuals on undifferentiated larvae of the parasitic nematode Paramermis contorta. Nature, London 207, 1105–6.CrossRefGoogle Scholar
Petersen, J. J. (1972). Factor affecting sex ratios of a mermithid parasite of mosquitos. Journal of Nematology 4, 83–7.Google Scholar
Poinar, G. O. Jr. & Hansen, E. (1983). Sex and reproductive modifications in nematodes. Helminthological Abstracts, Ser. B 52, 145–63.Google Scholar
Schad, G. A. (1977). The role of arrested development in the regulation of nematode populations. In Regulation of Parasite Populations (ed. Esch, G. W.), pp. 111–67. New York: Academic Press.Google Scholar
Self, J. T. & Pipkin, J. S. (1966). Sex distribution of the dioecious cestode Shipleya inermis Fuhrmann, 1908 in dowitchers. Journal of Parasitology 52, 45.CrossRefGoogle Scholar
Shaw, R. G. & Mitchell-Olds, T. (1993). Anova for unbalanced data: an overview. Ecology 74, 1638–45.CrossRefGoogle Scholar
Skadsheim, A., Christie, H. & Leinaas, H. P. (1995). Population reductions of Strongylocentrotus droebachiensis (O. F. Müller) (Echinodermata) in Norway and the distribution of its endoparasite Echinomermella matsi Jones & Hagen, 1987 (Nematoda). Marine Ecology-Progress Series, 119, 199–209.CrossRefGoogle Scholar
Stien, A. (1993). The ecology and epidemiology of Echinomermella matsi (Nematoda), a parasite of the sea urchin Strongylocentrotus droebachiensis. Cand. Scient. thesis, University of Oslo, Norway.Google Scholar
Tingley, G. A. & Anderson, R. M. (1986). Environmental sex determination and density-dependent population regulation in the entomogenous nematode Romanomermis culicivorax. Parasitology 92, 431–49.CrossRefGoogle Scholar
Triantaphyllou, A. C. (1973). Environmental sex differentiation of nematodes in relation to pest management. Annual Review of Phytopathology 11, 441–62.CrossRefGoogle Scholar
Zar, J. H. (1984). Biostatistical Analysis. 2nd Edn.Englewood Cliffs, NJ: Prentice Hall.Google Scholar
Zervos, S. (1988 a). Population dynamics of a thelastomatid nematode of cockroaches. Parasitology 96, 353–68.CrossRefGoogle Scholar
Zervos, S. (1988 b). Evidence for population self-regulation, reproductive competition and arrhenotoky in a thelastomatid nematode of cockroaches. Parasitology 96, 369–79.CrossRefGoogle Scholar