Section 52
Chapter 51,439

Allometry of sexual size dimorphism in domestic dog

Frynta, D.; Baudyšová, J.; Hradcová, P.; Faltusová, K.ři.; Kratochvíl, L.áš

Plos one 7(9): E46125


ISSN/ISBN: 1932-6203
PMID: 23049956
DOI: 10.1371/journal.pone.0046125
Accession: 051438189

Download citation:  

The tendency for male-larger sexual size dimorphism (SSD) to scale with body size - a pattern termed Rensch's rule - has been empirically supported in many animal lineages. Nevertheless, its theoretical elucidation is a subject of debate. Here, we exploited the extreme morphological variability of domestic dog (Canis familiaris) to gain insights into evolutionary causes of this rule. We studied SSD and its allometry among 74 breeds ranging in height from less than 19 cm in Chihuahua to about 84 cm in Irish wolfhound. In total, the dataset included 6,221 individuals. We demonstrate that most dog breeds are male-larger, and SSD in large breeds is comparable to SSD of their wolf ancestor. Among breeds, SSD becomes smaller with decreasing body size. The smallest breeds are nearly monomorphic. SSD among dog breeds follows the pattern consistent with Rensch's rule. The variability of body size and corresponding changes in SSD among breeds of a domestic animal shaped by artificial selection can help to better understand processes leading to emergence of Rensch's rule.

PDF emailed within 0-6 h: $19.90