Reduced Skull Sexual Dimorphism in a Local Sheep Breed

Subject Areas : Camel

P.M. Pares-Casanova ¹

1 - Department of Animal Production, University of Lleida, Av. Alcalde Rovira Roure, 191 25700 Lleida, Catalunya, Spain

Received: 2013-09-28 Accepted : 2013-10-15 Published : 2014-09-01

Keywords: Size, craniometric points, sexual dimorphism, shape, <i>Fardasca</i> breed,

Abstract :

This study estimated the magnitude of sexual dimorphism in a relict sheep from Catalunya (NE Spain), called Fardasca,using geometric morphometric techniques. For these analyses, a total of 18 skull specimens (2 adult males and 16 females) were studied. Our results suggest that the breed is not cranially dimorphic, so sex determination using landmarks described here as criteria is likely to yield poor results.

References:

Adams D. and Funk D.J. (1997). Morphometric inferences on sibling species and sexual dimorphism in Neochlamisus bebbianae leaf beetles: multivariate applications of the thin-plate spline. Sys. Biol. 46(1), 180-194.
Andersson M. (1994). Sexual Selection. Princeton: Princeton University Press.
Bookstein F.L. (1998). A hundred years of morphometrics. Acta Zool. Acad. Sci. Hung. 44, 7-59.
Dryden I. and Mardia K. (1998). Statistical Shape Analysis. Chichester: Wiley.
Hammer Ø., Harper D.A.T. and Ryan P.D. (2001). PAST: paleontological statistics software package for education and data analysis. Palaentologia electronica4(1). On line: http://palaeo-electronica.org/2001_1/past/issue1_01.html.
Gannon W.L. and Rácz G.R. (2006). Character displacement and ecomorphological analysis of two long-eared Myotis (M. auriculus and M. evotis). J. Mammal. 87(1), 171-179.
Kendall D.G. (1977). The diffusion of shape. Adv. Appl. Probab. 9, 428-430.
Klingenberg C.P. (2011). MorphoJ: an integrated software package for geometric morphometrics. Mol. Ecol. Res. 11, 353-357.
Lawing A.M. and Polly P.D. (2010). Geometric morphometrics: recent applications to the study of evolution and development. J. Zool. 280, 1-7.
LeBlanc M., Festa-Bianchet M. and Jorgenson J.T. (2001). Sexual size dimorphism in bighorn sheep (Ovis canadensis): effects of population density. Canadian J. Zool. 79, 1661-1670.
Marcus L., Bello E. and García-Valdecasas A. (1993). Contributions to morphometrics. Madrid: Monografias del Museo Nacional de Ciencias Naturales 8, Madrid.
Michelena P., Gerard J.F., Deneubourg J.L. and Bon R. (2006). Sexual dimorphism, activity budget and synchrony in groups of sheep. Oecologia. 148, 170-180.
Polák J. and Frynta D. (2009). Sexual size dimorphism in domestic goats, sheep, and their wild relatives. Biol. J. Linn. Soc. 98(4), 872-883.