Coevolution at Two Trophic Levels

  • S. D. Jayakar
Conference paper
Part of the Proceedings in Life Sciences book series (LIFE SCIENCES)

Abstract

Most of the classical populations genetics theories have till today dealt with models regarding genetic changes in a single species as a result of its interactions with its physical environment. Models dealing with competition between species have received some attention (Roughgarden 1979, Matessi and Jayakar 1980, Christiansen and Loeschcke 1980). It is clear, however, that any serious theoretical consideration of evolutionary mechanisms must take into account the coevolution, besides its competitors, also of its prey, its predators, and its parasites. Several models of gene frequency changes of such interactions have been proposed, but they suffer from the drawback that they deal only with gene frequencies and not with population sizes or densities (Mode 1958, Leonard 1977, Lewis 1981, Jayakar 1970). Roughgarden (1979) proposed a general ecological model of species interactions and considered several particular examples. Population sizes must be an essential feature of models involving two trophic levels since the possible extinction of food sources (or hosts) must govern the choice of organisms on which to feed or parasitize.

Keywords

Dikos 

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References

  1. Christiansen FB, Loeschcke V (1980) Intraspecific competition and evolution. In: Barigozzi C (ed) Vito Volterra Symposium on mathematical models in biology. Lecture notes in bio- mathematics 39. Springer, Berlin Heidelberg New YorkGoogle Scholar
  2. Jayakar SD (1970) A mathematical model for the interaction of gene frequencies in a parasite and its host. Theor Popul Biol 1:140–161PubMedCrossRefGoogle Scholar
  3. Leonard KJ (1977) Selection pressures and plant pathogens. Ann NY Acad Sci 287:201–222CrossRefGoogle Scholar
  4. Lewis JW (1981) On the coevolution of pathogen and host: I. General theory of discrete time coevolution; II. Selfing hosts and haploid pathogens. J Theor Biol 93:927–983PubMedCrossRefGoogle Scholar
  5. Matessi C, Jayakar SD (1980) Models of density-frequency dependent selection for the exploitation of resources. II. In: Barigozzi C (ed) Vito Volterra Symposium on mathematical models in biology. Lecture notes in biomathematics 39. Springer, Berlin Heidelberg New YorkGoogle Scholar
  6. Mode CJ (1958) A mathematical model for the coevolution of obligate parasites and their hosts. Evolution 12:158–165CrossRefGoogle Scholar
  7. Rossi L, Fano ED (1979) Role of fungi in the trophic niche of the congeneric detritivorous Asellus aquaticus and Proasellus coxalis. Oikos 32:380–385CrossRefGoogle Scholar
  8. Rossi L, Basset A, Marchetti E (1981) Predazione ed evoluzione della nicchia trofica in cinque specie di detrivori bentonici. Boll Zool 48:97–98CrossRefGoogle Scholar
  9. Roughgarden J (1979) Theory of population genetics and evolutionary ecology: an introduction. Macmillan, New YorkGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1984

Authors and Affiliations

  • S. D. Jayakar
    • 1
  1. 1.Department of Genetics and MicrobiologyUniversity of PaviaPaviaItaly

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