Sexual Size Dimorphism in Swine Denies Rensch’s Rule

Authors

  • Pere M. Parés-Casanova Dept. of Animal Production Univ, of Lleida (Catalunya, Spain)

Keywords:

body mass, differentiation of breed, domestication, sexual selection, Suidae

Abstract

Sexual dimorphism, defined as a phenotypic difference between males and females of a species, is a common phenomenon in animals. Rensch’s rule describes the pattern of sexual size dimorphism, claiming that larger species generally exhibit higher male to female body size ratios. Offering domesticated animals excellent opportunities for testing predictions of functional explanations of Rensch’s theory, we have tested in this paper whether the morphological size of domestic pig breeds follows this rule. We analysed the literature data on adult body size (live weight and withers height) of males and females in 130 contemporary domestic swine breeds and 4 wild Sus species. The analysis confirmed that the pattern of sexual size dimorphism in domestic swine does not conform to Rensch’s rule. It is proposed that this is due to the fact that males and females have been subjected not solely to a sexual selection regimen, but also to environmental factors, interspecific competition with other domestic species, an increase of intersexual food competition, poor feeding resources, and reproductive functional constraints. Considering all of the breeds studied, it is also likely that different counteracting selective pressures exist worldwide.

 

Author Biography

Pere M. Parés-Casanova, Dept. of Animal Production Univ, of Lleida (Catalunya, Spain)

Dept. of Animal Production

References

Abouheif, E., Fairbairn, D.J. A comparative analysis of allometry for sexual size dimorphism:assessing Rensch’s rule. Am. Nat. 149:540-562, 1997.

Andersson, M. Sexual selection. Princeton University Press, Princeton, N.J., 1994.

Arbuckle, S. Experimental animal domestication and its application to the study of animal exploitation in pre history. Vigne, J-D, Peters, J., Helmer, D. (eds.). The First Steps of Animal Domestication: New Archaeological Approaches, 2005.

Clutton-Brock, J. Domesticated animals from early times. Austin, TX: University of Texas Press, 1981.

Dale, J., Dunn, P.O., Figuerola, J., Lislevand, T., Székely, T., Whittingham, L.A. Sexual selection explains Rensch’s rule of allometry for sexual size dimorphism. Proc. R. Soc. Lond. B 274:2971-2979, 2007.

Darwin, C. The Variation of Animals and Plants under Domestication. John Murray, London, 1868.

Darwin, C. The descent of man, and selection in relation to sex. D. Appleton, New York, 1871.

Estes, R.D. The behavior guide to African mammals. University of California Press Ltd. Oxford, 1982.

Fairbairn, D.J. Allometry for sexual size dimorphism: pattern and process in the coevolution of body size in males and females. Ann. Rev. Ecol. Systs. 28: 659-687, 1997.

Frynta, D., Baudyšová, J., Hradcová, P., Faltusová, K. Kratochvíl, L. Allometry of Sexual Size Dimorphism in Domestic Dog. Plos One 7 (9), 2012.

Hammer, Ø., Harper, D.A.T., Ryan, P.D. PAST: Paleontological Statistics Software Package for Education and Data Analysis. Paleont. Elec. 4 (1), from http://palaeo-electronica.org/2001_1/past/issue1_01.html, 2001.

Jones, G. F. Genetic aspects of domestication, common breeds and their origin, pp. 17-50 in The Genetics of the Pig. Ruvinsky, A. (ed.) Rothschild M. F. CAB International, Oxon, UK, 1998.

Lovich, J.E., Gibbons, J.W. A review of techniques for quantifying sexual size dimorphism. Growth, Devel. Aging 56:269-281, 1992.

Paszek, A.A., Flickinger, G.H., Fontanesi, L., Beattie, C.W., Rohrer, G.A., et al. Evaluating evolutionary divergence with microsatellites. J. Mol. Evol. 46: 121-126, 19998.

Pérez-Barbería. F.J, Gordon, I.J., Pagel, M. The origins of sexual dimorphism in body size in ungulates. Evol. 56:1276-1285, 2002.

Polák, J., Frynta, D. Sexual size dimorphism in domestic goats, sheep, and their wild relatives. Biol. J. Linnean Soc. 98:872-883, 2009.

Polák, J., Frynta, D. Sexual size dimorphism in domestic cattle supports Rensch’s rule. Evol. Ecol. 24:1255-1266, 2010.

Raihani, G., Székely, T., Serrano-Meneses, M.A., Pitra, C., Goriup, P. The influence of sexual selection and male agility on sexual size dimorphism in bustards (Otididae). Anim. Behav. 71:833-838, 2006.

Ralls, K. Mammals in which females are larger than females. Quart. Rev. Biol. 51:245-276, 1976.

Rensch, B. Die Abhangigkeit der relativen Sexualdifferenz von der Korpergrosse. Bonner Zool. Beiträge 1:58-69, 1950.

Rensch, B. Evolution above the species level. Methuen & Co. Ltd. London, 1959.

Sambraus, H. H. A Colour Atlas of Livestock Breeds. Wolfe Publishing Ltd.Stuttgart. Stuttgart, 1992.

Székely, T., Freckleton, R.P., Reynolds, J.D. Sexual selection explains Rensch’s rule of size dimorphism in shorebirds. Proc. Natl. Acad. Sci. USA 101: 12224-12227, 2004.

Székely, T., Lislevand, T. and Figuerola, J. 2007. Sexual size dimorphism in birds. D.J. Fairbairn, W.U. Blanckenhorn and T. Székely, eds. Sex, Size and Gender Roles. Oxford University Press. Oxford.

Smith, R.J. 1999. Statistics of sexual size dimorphism. J. Hum. Evol. 36:423-459.

Wilson, D.E., Mittermeier, R.A. eds. 2011. Handbook of the Mammals of the World. Vol. 2 Hoofed Mammals. Lynx Edicions. Barcelona.

Downloads

Published

2013-10-14

How to Cite

Parés-Casanova, P. M. (2013). Sexual Size Dimorphism in Swine Denies Rensch’s Rule. Asian Journal of Agriculture and Food Sciences, 1(4). Retrieved from https://www.ajouronline.com/index.php/AJAFS/article/view/468