Multiple paternity is related to adult sex ratio and sex determination system in reptiles |
| |
Authors: | Ivett Pipoly Robert Duffy Gábor Mészáros Veronika Bókony Balázs Vági Tamás Székely András Liker |
| |
Institution: | 1. ELKH-PE Evolutionary Ecology Research Group, University of Pannonia, Veszprém, Hungary;2. Milner Centre for Evolution, Department of Biology & Biochemistry, University of Bath, Bath, UK;3. Centre for Ecological Research, Institute of Aquatic Ecology, Department of Tisza Research, Conservation Ecology Research Group, Debrecen, Hungary;4. Department of Evolutionary Ecology, Plant Protection Institute, Centre for Agricultural Research, Eötvös Loránd Research Network, Budapest, Hungary;5. ELKH-DE Reproductive Strategies Research Group, Department of Evolutionary Zoology and Human Biology, University of Debrecen, Debrecen, Hungary;6. Milner Centre for Evolution, Department of Biology & Biochemistry, University of Bath, Bath, UK
ELKH-DE Reproductive Strategies Research Group, Department of Evolutionary Zoology and Human Biology, University of Debrecen, Debrecen, Hungary |
| |
Abstract: | The adult sex ratio (ASR, the proportion of males in the adult population) is an emerging predictor of reproductive behaviour, and recent studies in birds and humans suggest it is a major driver of social mating systems and parental care. ASR may also influence genetic mating systems. For instance male-skewed ASRs are expected to increase the frequency of multiple paternity (defined here as a clutch or litter sired by two or more males) due to higher rates of coercive copulations by males, and/or due to females exploiting the opportunity of copulation with multiple males to increase genetic diversity of their offspring. Here, we evaluate this hypothesis in reptiles that often exhibit high frequency of multiple paternity although its ecological and life-history predictors have remained controversial. Using a comprehensive dataset of 81 species representing all four non-avian reptile orders, we show that increased frequency of multiple paternity is predicted by more male-skewed ASR, and this relationship is robust to simultaneous effects of several life-history predictors. Additionally, we show that the frequency of multiple paternity varies with the sex determination system: species with female heterogamety (ZZ/ZW sex chromosomes) exhibit higher levels of multiple paternity than species with male heterogamety (XY/XX) or temperature-dependent sex determination. Thus, our across-species comparative study provides the first evidence that genetic mating system depends on ASR in reptiles. We call for further investigations to uncover the complex evolutionary associations between mating systems, sex determination systems and ASR. |
| |
Keywords: | extra-pair paternity genetic mating system multiple mating phylogenetic comparative analysis sex chromosome social behaviour |
|
|