A unified-models analysis of the development of sexual size dimorphism in Damaraland mole-rats, Fukomys damarensis


Type
Article
Change log
Authors
Clutton-Brock, TH 
Abstract

jats:titleAbstract</jats:title>jats:pIndividual variation in growth rates often generates variation in fitness. However, the ability to draw meaningful inferences from growth data depends on the use of growth models that allow for direct comparisons of growth between the sexes, between populations, and between species. Unlike traditional sigmoid functions, a recently parameterized family of unified growth models provides a reliable basis for comparisons since each parameter affects a single curve characteristic and parameters are directly comparable across the unified family. Here, we use the unified-models approach to examine the development of sexual size dimorphism in Damaraland mole-rats (Fukomys damarensis), where breeding males are larger than breeding females. Using skeletal measurements, we show here that the larger size of male Damaraland mole-rats arises from an increased growth rate across the entire period of development, rather than through sex differences in the duration or timing of growth. Male-biased skeletal size dimorphism is not unusual among rodents, and our measures of sex differences in size in captive mole-rats are close to sexual size differences in the wild, where size dimorphism = 1.04 (male:female). We hope our study will encourage the wide use of unified growth models by mammalogists.</jats:p>

Description
Keywords
Bathyergidae, cooperative breeder, growth interval equations, nonlinear mixed-effects models, ontogeny, sexual dimorphism, sociality
Journal Title
Journal of Mammalogy
Conference Name
Journal ISSN
0022-2372
1545-1542
Volume Title
100
Publisher
Oxford University Press (OUP)
Rights
All rights reserved
Sponsorship
European Research Council (294494)
European Research Council (742808)
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