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The effect of selection on brain and body size association in rats

Published online by Cambridge University Press:  14 April 2009

William R. Atchley
William R. Atchley
Affiliation:
Department of Genetics, University of Wisconsin, Madison, Wisconsin 53706

Summary

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Changes in brain size, body size and their co variance are reported from a long-term replicated directional selection experiment on body weight gain in rats. Two strains had been selected for increased and two for decreased weight gain between 3 and 9 weeks of age, and there were two randomly selected control lines. Selection produced significant changes in body weight in all selected lines. Divergence from the controls occurred in brain size in those strains selected for increased weight gain; no significant divergence was found for the strains selected for decreased weight gain. Divergence among unselected control lines suggests that genetic drift occurred in expression of brain size. Sexual dimorphism in response to selection results from sex differences in heritabilities and genetic correlations in relevant traits. In spite of considerable change in body size and brain size, no significant change in their covariation occurred either between the selection lines or between sexes. The relevance of these results to a brain and body size ‘scaling effect’ during evolutionary divergence is discussed.

Type
Research Article
Information
Genetics Research , Volume 43 , Issue 3 , June 1984 , pp. 289 - 298
Copyright
Copyright © Cambridge University Press 1984

References

REFERENCES

Atchley, W. R. (1983). Some genetic aspects of morphometric variation. In Numerical Taxonomy (ed. Felsenstein, J.), pp. 346–363. Berlin: Springer-Verlag.CrossRefGoogle Scholar
Atchley, W. R. (1984). Ontogeny, timing of development and genetic variance-covariance structure. American Naturalist 123, 519–540.CrossRefGoogle Scholar
Atchley, W. R. & Rutledge, J. J. (1980). Genetic components of size and shape. I. Dynamics of components of phenotypic variability and covariability during ontogeny in the laboratory rat. Evolution 34, 1161–1173.CrossRefGoogle ScholarPubMed
Atchley, W. R., Rutledge, J. J. & Cowley, D. E. (1981). Genetic components of size and shape. II. Multivariate covariance patterns in the rat and mouse. Evolution 35, 1037–1055.CrossRefGoogle ScholarPubMed
Atchley, W. R., Rutledge, J. J. & Cowley, D. E. (1982). A multivariate statistical analysis of direct and correlated response to selection in the rat. Evolution 36, 677–698.CrossRefGoogle Scholar
Bakee, R. L. & Chapman, A. B. (1975). Correlated response to selection for postweaning gain in rats. Genetics 80, 191–203.Google Scholar
Baker, R. L., Chapman, A. B. & Wardell, R. T. (1975). Direct response to selection for postweaning gain in the rat. Genetics 80, 171–189.CrossRefGoogle ScholarPubMed
Dubois, E. (1897). Sur le rapport du poids de l'encéphale avec la grandeur du corps chez les mammiferes. Bulletin de la Société d'anthropologie de Paris 8, 337–376.CrossRefGoogle Scholar
Falconer, D. S. (1981). Introduction to Quantitative Genetics, 2nd ed.London: Longman.Google Scholar
Gould, S. J. (1966). Allometry and size in ontogeny and phylogeny. Biological Reviews 41, 587–640.CrossRefGoogle ScholarPubMed
Gould, S. J. (1975). Allometry in primates, with emphasis on scaling and the evolution of the brain. Contributions in Primatology 5, 244–292.Google ScholarPubMed
Gould, S. J. (1977). Ontogeny and Phylogeny. Cambridge: Belknap Press.Google Scholar
Hahn, M. E., Jensen, C. & Dudek, B. C. (eds.) (1979). Development and Evolution of Brain Size. New York: Academic Press.Google Scholar
Huxley, J. S. (1932). Problems of Relative Growth. London: MacVeagh.Google Scholar
Jerison, H. J. (1973). Evolution of Brain Size and Intelligence. New York: Academic Press.Google Scholar
Kobayashi, T. (1963). Brain-to-body ratios and time of maturation of the mouse brain. American Journal of Physiology 204, 343–346.CrossRefGoogle ScholarPubMed
Lande, R. (1979). Quan titative genetic analysis of multivariate evolution applied to brain: body size allometry. Evolution 33, 402–416.Google Scholar
Lapique, L. (1898). Sur la relation du poids de l'encéphale au poids du corps. Comptes rendus de la Société de biologie filiales 50, 62–63.Google Scholar
Lapique, L. (1907). Tableau générale des poids somatiques et encéphaliques dans les espèces animales. Bulletin de la Société d'anthropologie de Paris 8, 248–262.Google Scholar
Martin, R. D. (1981). Relative brain size and basal metabolic rate in terrestrial vertebrates. Nature 293, 57–60.CrossRefGoogle ScholarPubMed
Radinsky, L. (1977). Brains of early carnivores. Paleobiology 3, 333–349.CrossRefGoogle Scholar
Radinsky, L. (1978). Evolution of brain size in carnivores and ungulates. American Naturalist 112, 815–831.CrossRefGoogle Scholar
Riska, B., Atchley, W. R. & Rutledoe, J. J. (1984). A genetic analysis of targeted growth in mice. Genetics. (In the Press.)CrossRefGoogle ScholarPubMed
Roderick, T. H., Wimer, R. E. & Wimer, C. C. (1976). Genetic manipulation of neuroanatomical traits. In Knowing, Thinking and Believing (eds. Petrinovich, L. and McGaugh, J. L.). New York: Plenum Press.Google Scholar
Sacher, G. A. & Staffeldt, E. F. (1974). Relation of gestation time to brain weight for placental mammals: Implication for the theory of vertebrate growth. American Naturalist 108, 593–616.CrossRefGoogle Scholar
Szarski, H. (1980). A functional and evolutionary interpretation of brain size in vertebrates. Evolutionary Biology 13, 149–174.CrossRefGoogle Scholar
Wood, B. A. (1978). Allometry and hominid studies. In Geological Background to Fossil Man (ed. Bishop, W. W.), pp. 125–138.CrossRefGoogle Scholar
Zar, J. H. (1974). Biostatistical Analysis. Englewood Cliffs: Prentice-Hall.Google Scholar