Brood‐tending males in a biparental fish suffer high paternity losses but rarely cuckold

Abstract

Extra‐pair paternity within socially monogamous mating systems is well studied in birds and mammals but rather neglected in other animal taxa. In fishes, social monogamy has evolved several times but few studies have investigated the extent to which pair‐bonded male fish lose fertilizations to cuckolders and gain extra‐pair fertilizations themselves. We address this gap and present genetic paternity data collected from a wild population of Variabilichromis moorii, a socially monogamous African cichlid with biparental care of offspring. We show that brood‐tending, pair‐bonded males suffer exceptionally high paternity losses, siring only 63% of the offspring produced by their female partners on average. The number of cuckolders per brood ranged up to nine and yet, surprisingly, brood‐tending males in the population were rarely the culprits. Brood‐tending males sired very few extra‐pair offspring, despite breeding in close proximity to one another. While unpaired males were largely responsible for the cuckoldry, pair‐bonded males still enjoyed higher fertilization success than individual unpaired males. We discuss these results in the context of ecological and phenotypic constraints on cuckoldry and the fitness payoffs of alternative male tactics. Our study provides new insights into how pair‐bonded males handle the trade‐off between securing within‐pair and extra‐pair reproduction.

Congruent geographic variation in saccular otolith shape across multiple species of African cichlids

“…These species were selected because they were particularly abundant at all locations and represent a sample of species that shares many similarities in ecology and niche-space. For example, all four species are small-bodied cichlids (typical standard lengths for breeding individuals are: 6.0 cm for N. pulcher 32 34,37 ). Their diets are also similar, consisting of pelagic zooplankton, though V. moorii also commonly grazes on algae 36,37 .…”

“…Fish euthanized in this study were also used in numerous additional research projects (e.g. Bose et al 34 ) including studies of parental care, mating behaviours, and parasite load.…”

“…caudopunctatus 35 ). Their distributions are all geographically limited to rocky littoral zones, and their depth ranges overlap ( N. pulcher : 4–20 m, N. savoryi : 4–20 m, N. caudopunctatus : shallow—25 m 36 ; V. moorii : 2–13 m 34 , 37 ). Their diets are also similar, consisting of pelagic zooplankton, though V. moorii also commonly grazes on algae 36 , 37 .…”

Cuckolding and Troilism: definitions, relational and clinical contexts, emotional and sexual aspects, and neurobiological profiles. A complete review and investigation into the borderline forms of the relationship: Open Couples, Polygamy, Polyamory

“…The sexual act performed by one of the two partners of the main couple is experienced by the other as a violence to the person or as a humiliation capable of provoking denigration since emotionally it is not the couple who plays or decides the rules but it is only one of the two components and the other is the victim of the game or the clandestine relationship. The word used in this context, "cuckold" (masculine) or "reverse cuckold or cuckquean" (feminine), which derives from the medieval French "cucuault", literally means "the bad cuckoo", about the female of the cuckoo who is said that often changes In the animal kingdom, this practice is rather studied about fertilization possibilities and the increase in opportunities for procreative purposes, especially in mammals and birds [4] and less in the marine kingdom [5].…”

Inclusive fitness benefits mitigate costs of cuckoldry to socially paired males

“…55.1%, ref. [31]). Up to 100% of nests can contain extra-pair offspring, and the number of extra-pair sires per brood can sometimes surpass 10 males [32].…”