Predictably Philandering Females Prompt Poor Paternal Provisioning

Abstract

Dryad data: http://dx.doi.org/10.5061/dryad.0t313.abstract: One predicted cost of female infidelity in socially monogamous species is that cuckolded males should provide less parental care. This relationship is robust across species, but evidence is ambiguous within species. We do not know whether individual males reduce their care when paired with cheating females compared with when paired with faithful females (within-male adjustment) or, alternatively, if the males that pair with cheating females are the same males that provide less parental care in general (between-male effect). Our exceptionally extensive long-term data set of repeated observations of a wild passerine allows us to disentangle paternal care adjustment within males-within pairs and between males-while accounting for environmental variables. We found a within-male adjustment of paternal provisioning, but not incubation effort, relative to the cuckoldry in their nest. This effect was mainly driven by females differing consistently in their fidelity. There was no evidence that this within-male adjustment also took place across broods with the same female, and we found no between-male effect. Interestingly, males that gained more extrapair paternity provided less care. Data from a cross-foster experiment suggested that males did not use kin recognition to assess paternity. Our results provide insight into the role of individual variation in parental care and mating systems.

Correlates of complete brood failure in blue tits: could extra‐pair mating provide unexplored benefits to females?

“…The 'good genes' hypothesis therefore does not seem supported in this population, and more importantly, 'good genes' effects could not explain why all nestlings in a brood would survive better, regardless of the genes they may carry, when the brood is sired by more than one male. Finally, given the common expectation that cuckolded males should provide less care and protection for their brood due to low paternity (but see Schroeder et al 2016), our observations require alternative explanations. A first tentative explanation for the difference in brood failure between brood types is that areas differed in both resource availability and extra-pair mating, with extra-pair mating higher in areas of high food abundance or low predation risk.…”

“…While we did not find any difference in age, body size, body condition, or breeding phenology between mothers of mixed-paternity broods and those of single-paternity broods, we did however not directly measure their behaviour, and cannot rule out that they might have differed in some other traits. This might also apply to males, and in particular the link between male propensity to loose paternity and the level of protection and care received by their brood (Patrick et al 2012, Schroeder et al 2016, is an aspect that would require further investigation. However, differences in behavioural traits alone would not suffice to explain why older male neighbours would sire more EP offspring, irrespective of other phenotypic traits.…”

“…Extra-pair copulation (EPC) and its outcome, extra-pair paternity (EPP), are known to be widespread amongst socially monogamous birds (Griffith et al 2002). In such systems males are predicted to reduce their parental investment when paternity in the nest is low or uncertain, and hence EPC is expected to increase the reproductive burden for promiscuous females (Westneat and Sherman 1993, Kempenaers and Sheldon 1997, Arnqvist and Kirkpatrick 2005, Houston et al 2005, Schroeder et al 2016). However, since EPC is a widespread strategy across avian taxa, it has been suggested that benefits from EPC could be gained not only by cuckolding males, but also by their female partners.…”

Matrilateral Bias in Human Grandmothering

“…The first is the species-or population-specific rate of "extra-pair" paternity ("cuckoldry"), which helps explain "fixed" differences between taxa in such matters as whether male birds incubate their partners' eggs (e.g., Møller and Birkhead, 1993). The second is a psychological variable, responsive to cues of paternity probability including the timing of a mate's absences and the phenotypic resemblance of father and offspring, which helps explain individual differences in such things as male participation in feeding the young (e.g., Schroeder et al, 2016). As a result of a history of natural selection, both the population parameter and the individual difference variable influence paternal care, mate guarding, patrilateral kin investment, and other social phenomena in many species (Daly and Wilson, 1988).…”

Size of nest‐cavity entrance influences male attractiveness and paternal provisioning in house wrens

“…Trivers, 1972;Queller, 1997;Bowers et al, 2014aBowers et al, , 2015b. In species with biparental care, females often copulate with males other than the one with which they form a social bond, and the cuckolded males often respond by reducing their parental investment commensurate with their decreased confidence of paternity in the brood (Matysiokov a & Reme s, 2013;Schroeder et al, 2016). Indeed, selection should favor plasticity that allows individuals to recognize the optimal behavioral strategy in any given context.…”