Author(s): Mónus, F. & Barta, Z.
Title: Repeatability analysis of egg shape in a wild Tree Sparrow (Passer montanus) population: a sensitive method for egg shape description
Year: 2005
Volume: 51
Pages: 151-162.
Abstract: The shape of avian eggs varies widely among and within species. To explore this variation, several methods for egg shape description were used in previous works. The simplest methods were unsuitable to detect small differences in shape of different eggs, while more elaborated methods required special equipment, since they were not generally used. In this study we present a simple method for egg shape description which incorporate quickness in the field, high sensitivity to egg shape differences and furthermore require no special equipment. The method is based on a function which describe the outline of the egg in a two dimensions co-ordinate system and outline originates from field taken photographs. The method was tested on clutches of wild living Tree Sparrow (Passer montanus) population. Three out of four parameters of the function were found to be repeatable in Tree Sparrows. The eggs of repetitive clutches of females were more similar considering these egg shape parameters than eggs of different females. A simple, widely used index to describe egg shape, egg shape index was found to be far less sensitive in our repeatability analyses. The method described here may be particularly suitable to investigate intraspecific variation of egg shape.
Keywords: Passer montanus, description, egg shape, repeatability, Tree Sparrow
Journal: Acta Zoologica Academiae Scientiarum Hungaricae
Journal abbreviation:
ISSN: 1217-8837
Publisher: Hungarian Natural History Museum, Budapest
Editor(s): Bakonyi, G. & Peregovits, L.
