Hostname: page-component-848d4c4894-wg55d Total loading time: 0 Render date: 2024-05-13T16:36:44.679Z Has data issue: false hasContentIssue false

Population size structure and sex ratios in some woodlice (Crustacea: Oniscidae) from southern Africa

Published online by Cambridge University Press:  10 July 2009

J. M. Dangerfield
Affiliation:
Department of Biology, University of Botswana, Private Bag 0022, Gaborone, Botswana.
S. R. Telford
Affiliation:
Department of Zoology, University of Pretoria, Pretoria 0002, South Africa.

Abstract

The population size structure and adult sex ratio were recorded for four indigenous and one introduced species of terrestrial isopod from southern Africa. Interspecific variation was considerable with either discrete or continuous distributions indicative of the production of separate cohorts or continuous recruitment. Intraspecific variation was also considerable particularly in species such as Aphiloscia vilis which can be found in diverse habitats. Sex ratios were consistently female biased, a result consistent with observations made on temperate species. These observations, and a consideration of sexual dimorphism based on body mass, suggest that phenotypic plasticity may be an important tactic in the life histories of tropical woodlice and that in some populations the potential exists for strong sexual competition and complex mating systems.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1994

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

LITERATURE CITED

Al-Dabbagh, K. Y. & Block, W. 1981. Population ecology of a terrestrial isopod in two Breckland grass heaths. Journal of Animal Ecology 50:6177.CrossRefGoogle Scholar
Caswell, H. 1983. Phenotypic plasticity in life-history traits:, demographic effects and evolutionary consequences. American Zoologist 23:3546.CrossRefGoogle Scholar
Dangerfield, J. M. 1990. Abundance, biomass and diversity of soil macrofauna in savanna woodland and associated managed habitats. Pedobiologia 34:141151.CrossRefGoogle Scholar
Dangerfield, J. M. & Hassall, M. 1992. Phenotypic variation in the breeding phenology of the woodlouse Amadillidium vulgare. Oecologia 89:140146.CrossRefGoogle ScholarPubMed
Dangerfield, J. M., Milner, A. E. & Matthews, R. 1992. Seasonal activity patterns and behaviour of julid millipedes in south-eastern Botswana. Journal of Tropical Ecology 8:451464.CrossRefGoogle Scholar
Dangerfield, J. M. & Telford, S. R. 1990. Breeding phenology, variation in reproductive effort and offspring size in a tropical population of the woodlouse Porcetlliondes pruinosus. Oecologia 82:251258.CrossRefGoogle Scholar
Dangerfield, J. M. & Telford, S. R. 1991. Distribution patterns of Aphiloscia maculicornis Budde-Lund (Crustacea, Oniscidae) in a moist tropical forest above Victoria Falls, Zimbabwe. In The Biology of Terrestrial Isopods III. Proceedings of the Third International Symposium on the Biology of Terrestrial Isopods. Juchault, P. & Mocquard, J. P. (eds). Universite de Poitiers, France.Google Scholar
Davis, R. C. 1984. The effects of weather and habitat structure on the population dynamics of three species of woodlice (Crustacea: Oniscoidea) in a dune grassland. Oikos 42:387395.CrossRefGoogle Scholar
Deevey, E. S. 1947. Life tables for natural populations of animals. Quarterly Review of Biology 22:283314.CrossRefGoogle ScholarPubMed
Emlen, S. T. & Oring, L. W. 1977. Ecology, sexual selection and the evolution of mating systems. Science 197:215223.CrossRefGoogle ScholarPubMed
Ferrara, F. & Taiti, S. 1979. A check-list of terrestrial isopods from Africa (south of the Sahara). Monitore Zoologico Italiano, Supplement 12, 10:89215.CrossRefGoogle Scholar
Ferrara, F., Argano, R., Manicastri, C., Schmalfuss, H. & Taiti, S. (eds.) 1989. Proceedings of the Second Symposium of the Biology of Terrestrial Isopods. Monitore zoologico italiano N.S. Monografia 4. Universita di Firenze.Google Scholar
Fisher, R. A. 1930. The genetical theory of natural selection. Clarendon Press, Oxford.CrossRefGoogle Scholar
Hassall, M. & Dangerfield, J. M. 1990. Density-dependent processes in the population dynamics of Amadillidium vulgare (Isopoda: Oniscidae). Journal of Animal Ecology 59:941958.CrossRefGoogle Scholar
Hassall, M., Dangerfield, J. M., Manning, T. P. & Robinson, F. G. 1988. A modified high-gradient extractor for multiple samples of soil macro-arthropods. Pedobiologia 32:2130.CrossRefGoogle Scholar
Howard, H. W., 1942. The genetics of Armadilliditm vulgare Latr. II. Studies on the inheritance of monogeny and amphogeny. Journal of Genetics 44:143159.CrossRefGoogle Scholar
Howard, H. W. 1980. The distribution at breeding time of the sex of the woodlouse Armadillidium vulgare Latreille (Isopoda). Crustaceana 39:5258.CrossRefGoogle Scholar
Ma, H. H. T., Dudgeon, D. & Lam, P. K. S. 1991a. Seasonal changes in populations of three sympatric isopods in a Hong Kong forest. Journal of Zoology (London) 224:347365.CrossRefGoogle Scholar
Ma, H. H. T., Lam, P. K. S. & Dudgeon, D. 1991b. Inter- and intraspecific variation in the life histories of three sympatric isopods in a Hong Kong forest. Journal of Zoology (London) 224:677–387.CrossRefGoogle Scholar
Paris, O. H. 1963. The ecology of Armadillidium vulgare in Californian grassland: Food, enemies and weather. Ecological Monographs 33:122.CrossRefGoogle Scholar
Radu, V. & Tomescu, N. 1976. Quantitativ-okologische untersuchungen an landisopoden. Pedobiologia 16:3643.CrossRefGoogle Scholar
Rigaud, T., Juchault, P. & Mocquard, J.-P. 1991a. Experimental study of temperature effects on the sex ratio of broods in the terrestrial Crustacea Armadillidium vulgare Latr. Possible implications in natural populations. Journal of Evolutionary Biology 4:603617.CrossRefGoogle Scholar
Rigaud, T., Souty-Grosset, C., Raimond, R., Mocquard, J.-P. & Juchault, P. 1991b. Feminizing endocytobiosis in the terrestrial crustacean Armadillidium vulgare Latr. (Isopoda): Recent acquisitions. Endocytobiosis and Cell Research 7:259273.Google Scholar
Sunderland, K. D., Hassall, M. & Sutton, S. L. 1976. The population dynamics or Philoscia muscorum (Crustacea: Oniscoidea) in a dune grassland ecosystem. Journal of Animal Ecology 45:487506.CrossRefGoogle Scholar
Sutton, S. & Holdich, D. M. (eds). 1984. The biology of terrestrial isopods. Zoological Society of London Symposia 53. Oxford Scientific Publications.Google Scholar
Sutton, S. L., Hassall, M., Willows, R. A., Davis, R. C., Grundy, A. & Sunderland, K. D. 1984. Life histories of terrestrial isopods. Symposium of the Zoological Society London 53:269294.Google Scholar
Swift, M. J., Heal, O. W. & Anderson, J. M. 1979. Decomposition in terrestrial ecosystems. Blackwell Scientific Publications, Oxford.CrossRefGoogle Scholar
Warburg, M. 1987. Isopods and their terrestrial environment. Advances in Ecological Research 17:187242.CrossRefGoogle Scholar
Warburg, M. R., Linsenmair, K. E. & Bercovitz, K. 1984. The effect of climate on the distribution and abundance of isopods. Symposium of the Zoological Society, London 53:339367.Google Scholar
Willows, R. 1984. Breeding phenology of woodlice and oostegite development in Ligia oceanica (L.) (Crustacea). Symposium of the Zoological Society, London 53:469485.Google Scholar
Willows, R. 1987. Population dynamics and life history of two contrasting populations of Ligia oceanica (Crustacea: Oniscidae) in the rocky supralittoral. Journal of Animal Ecology 56:315330.CrossRefGoogle Scholar