Passerine extrapair mating dynamics: a bayesian modeling approach comparing four species.
In many socially monogamous animals, females engage in extrapair copulation (EPC), causing some broods to contain both within-pair and extrapair young (EPY). The proportion of all young that are EPY varies across populations and species. Because an EPC that does not result in EPY leaves no forensic trace, this variation in the proportion of EPY reflects both variation in the tendency to engage in EPC and variation in the extrapair fertilization (EPF) process across populations and species. We analyzed data on the distribution of EPY in broods of four passerines (blue tit, great tit, collared flycatcher, and pied flycatcher), with 18,564 genotyped nestlings from 2,346 broods in two to nine populations per species. Our Bayesian modeling approach estimated the underlying probability function of EPC (assumed to be a Poisson function) and conditional binomial EPF probability. We used an information theoretical approach to show that the expected distribution of EPC per female varies across populations but that EPF probabilities vary on the above-species level (tits vs. flycatchers). Hence, for these four passerines, our model suggests that the probability of an EPC mainly is determined by ecological (population-specific) conditions, whereas EPF probabilities reflect processes that are fixed above the species level.
Department of Biosciences, University of Helsinki, FIN-00014 Helsinki, Finland. jon.brommer@helsinki.fi
Jon E
JE
Brommer
Jussi S
JS
Alho
Clotilde
C
Biard
Joanne R
JR
Chapman
Anne
A
Charmantier
Amelie
A
Dreiss
Ian R
IR
Hartley
Mårten B
MB
Hjernquist
Bart
B
Kempenaers
Jan
J
Komdeur
Toni
T
Laaksonen
Paula K
PK
Lehtonen
Thomas
T
Lubjuhn
Samantha C
SC
Patrick
Balázs
B
Rosivall
Joost M
JM
Tinbergen
Marco
M
van der Velde
Kees
K
van Oers
Tomasz
T
Wilk
Wolfgang
W
Winkel
D000818:Animals; D001499:Bayes Theorem; D005260:Female; D005838:Genotype; D008297:Male; D046109:Passeriformes / Q000235:genetics / Q000502:physiology*; D011157:Population Dynamics; D012726:Sexual Behavior, Animal; D013045:Species Specificity