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Copyright of Therya is the property of Asociacion Mexicana de Mastozoologia, A. C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mating systems constitute an important biological characteristic that must be evaluated in commercially important species due to the effects of these systems on population growth rates and genetic diversity levels, which in turn determine the evolutionary potential of a population in the presence of environmental change. The most commonly reported mating system in sharks is polyandry, yet isolated reports of genetic monogamy have been published. The present study aimed to infer the mating system of two gravid Mustelus californicus females from Puerto Libertad, Sonora. The genetic analyses and parental reconstructions from the litters of both females indicated that genetic monogamy was most likely at work. We also discuss the ecological and biological features that may support genetic monogamy in this species. This is the first record of this mating system in M. californicus, which provides baseline data for future studies. [ABSTRACT FROM AUTHOR]

Individuals of either sex may display alternative behaviors to obtain copulations, but few studies have examined the breeding patterns of females and males in populations where individuals of both sexes exhibit alternative reproductive tactics (ARTs). In prairie voles (Microtus ochrogaster), most adults are territorial, residing at a single nest site either as male–female pairs or as solitary individuals. However, some adults adopt nonterritorial, wandering tactics. During two field seasons monitoring prairie vole populations maintained in seminatural enclosures, we found evidence that females exhibiting different ARTs bred differentially with resident and wandering males. Females residing at a nest with a male bred significantly more often with a paired resident male, primarily their social partner, and significantly less often with male wanderers compared to single resident females or wandering females. These patterns were not due to chance, because paired resident females produced offspring with paired resident males significantly more than expected based on the relative abundance of these males in the population, whereas single resident females produced offspring with male wanderers significantly more than expected based on the proportion of male wanderers in the population. We did not find any evidence that multiple paternity was greater in the litters of single resident females and wanderer females even though these females lacked a male social partner to limit mating access by multiple males. This suggests that mate guarding by a female's male social partner was not the primary determinant of multiple paternity in the litters of females exhibiting different reproductive tactics. However, male ART did affect the likelihood of multiple paternity. Females that produced offspring with single resident or wanderer males had an increased likelihood of multiple paternity relative to females producing offspring with paired resident males. The results of this study show that female and male ARTs can affect breeding patterns. [ABSTRACT FROM AUTHOR]

Background: We still do not understand the key drivers or prevalence of genetic monogamy in mammals despite the amount of attention that the evolution of mammalian monogamy has received. There have been numerous reviews of the hypotheses proposed to explain monogamy, some of which focused on animals in general, while others focused on particular classes like birds or mammals, or on specific orders within a class. Because monogamy is rare in mammals overall but relatively common in some of the orders in which it has been observed (e.g., Primates, Macroscelidea, and Carnivora), mammals provide a unique taxon in which to study the evolution and maintenance of monogamy However, the term “monogamy” encompasses related but separate phenomena; i.e., social monogamy (pair-living by opposite-sex conspecifics) and genetic monogamy or reproductive monogamy (mating exclusivity). A recent review of mammalian monogamy reported that 226 species (9%) in 9 orders (35%) were socially monogamous, although socially monogamous mammals are not necessarily genetically monogamous.Methods: Since factors that predispose socially monogamous mammals to be genetically monogamous are still subject to debate, we conducted meta-analyses using model selection to determine the relative importance of several life history, demographic, and environmental factors in predicting genetic monogamy.Results: We found sufficient data to include 41 species in our analysis, about 2x more than have been included in previous analyses of mammalian genetic monogamy. We found that living as part of a socially monogamous pair vs. in a group was the best predictor of genetic monogamy, either by itself or in combination with high levels of paternal care. A male-biased sex ratio and low population density were inversely related to the number of pairs that were genetically monogamous, but not to the production of intra-pair young or litters.Conclusion: Our results agree with the results of some previous analyses but suggest that more than one factor may be important in driving genetic monogamy in mammals.

Molecular markers can reveal interesting aspects of organismal ecology and evolution, especially when surveyed in rare or elusive species. Herein, we provide a preliminary assessment of golden eagle ( Aquila chrysaetos) population structure in North America using novel single nucleotide polymorphisms (SNPs). These SNPs included one molecular sexing marker, two mitochondrial markers, 85 putatively neutral markers that were derived from noncoding regions within large intergenic intervals, and 74 putatively nonneutral markers found in or very near protein-coding genes. We genotyped 523 eagle samples at these 162 SNPs and quantified genotyping error rates and variability at each marker. Our samples corresponded to 344 individual golden eagles as assessed by unique multilocus genotypes. Observed heterozygosity of known adults was significantly higher than of chicks, as was the number of heterozygous loci, indicating that mean zygosity measured across all 159 autosomal markers was an indicator of fitness as it is associated with eagle survival to adulthood. Finally, we used chick samples of known provenance to test for population differentiation across portions of North America and found pronounced structure among geographic sampling sites. These data indicate that cryptic genetic population structure is likely widespread in the golden eagle gene pool, and that extensive field sampling and genotyping will be required to more clearly delineate management units within North America and elsewhere. [ABSTRACT FROM AUTHOR]

The article discusses a study that tested the hypothesis that the Taiwan vole Microtus kikuchii is both socially and genetically monogamous. Field information of home ranges was combined with genetic analysis of relationships among individual voles. DNA of the voles was amplified through microsatellite loci using primers designed for M. oeconomus and M. montebelli. Genetic analysis showed that several of the male-female pairs identified via overlapping home ranges did not reproduce. It was found that none of the litters in the study with multiple offspring had more than one father. The hypotheses regarding the social and genetic monogamy of the voles was reinforced.

Variation in ecological and demographic characteristics may alter the value of extrapair paternity (EPP) for socially monogamous species, thereby leading to variation in mating strategies among conspecific populations. Environmental factors influencing the need for parental care, and demographic factors influencing relatedness of social pairs or availability of unrelated extrapair partners, are both predicted to influence the direct and indirect benefits of EPP in cooperatively breeding birds. We examined genetic mating strategies in 3 long-term study populations of cooperatively breeding Florida scrub-jays (FSJs; Aphelocoma coerulescens) in which the value of EPP—or opportunities for it—was likely to vary: a fragmented site with a high frequency of inbreeding (potentially elevating the value of EPP as a means of increasing offspring heterozygosity); a suburban population with high rates of brood reduction (potentially elevating the value of shared parental investment); and a wildland site with a high frequency of unrelated breeders and opposite-sex auxiliaries (potentially elevating the opportunity for shared within-group parentage). Despite these differences, genetic monogamy dominated at all sites: 100% of the offspring sampled from the suburban site (144 offspring) and fragmented site (258 offspring), and 99.5% of offspring from the wildland site (367 of 369 offspring) were produced monogamously. Rare exceptions in our study populations demonstrate that, even in the FSJ, genetic monogamy is a plastic trait. The near ubiquity of genetic monogamy across 3 ecologically different study sites, however, suggests that this tendency toward monogamy is impervious to the population-level environmental and social variation that we documented. [ABSTRACT FROM PUBLISHER]

Because of female-biased illegal harvesting, knowledge about the genetic mating system of the black spiny-tailed iguana Ctenosaura pectinata is of primary interest for the conservation of this threatened species. Based on the high levels of multiple paternity found in clutches of many other reptiles, particularly in lizards, it is hypothesised that multiple paternity may also be common in black iguanas. This was investigated by using microsatellite DNA to estimate the number of males siring nine litters (9 mothers, 121 offspring genotyped at ten polymorphic loci) of black iguanas. Contrary to expectations, only 11% of sampled black iguana females produced litters consistent with being sired by multiple males. These data are the first evidence for the predominance of single paternity within an iguanid lizard, and suggest that black iguana may be more susceptible to loss of genetic variation in the face of gender-biased over-hunting pressure than previously thought. [ABSTRACT FROM AUTHOR]

We investigated sexual conflict over parental care in blue-headed vireos ( Vireo solitarius) and documented the first example of unvarying unisexual brood desertion in passerines. Females at all nests ( N = 24) that were monitored closely near fledgling, deserted their broods on or near the day of fledging leaving males alone to complete parental care of young. No males deserted. This observational evidence was confirmed with radiotracking of females (2004, 2007) and both pair members (2008). Radiotracked females began visiting distant males 1–4 days before young left the nest, subsequently paired with males 355–802 m away, and laid first eggs in new nests less than 5 days after deserting. In contrast, females suffering nest predation did not desert and renested with the same male. We suggest equal parental care (nest building, incubation, feeding) in the sexes, genetic monogamy, and an adult sex ratio biased towards males has led to female control of brood desertion in this species. Unisexual desertion may be more important in altricial birds than generally realized and we discuss prerequisites to predict its occurrence. One is genetic monogamy, which may be a female tactic that reduces the likelihood of males evolving counter-adaptations to female desertion. [ABSTRACT FROM AUTHOR]

Integrative studies of genetics, neurobiology and behaviour indicate that polymorphism in specific genes contributes to variation observed in some complex social behaviours. The neuropeptide arginine vasopressin plays an important role in the regulation of a variety of social behaviours, including social attachment of males to females, through its action on the vasopressin 1a receptor (V1aR). In socially monogamous prairie voles ( Microtus ochrogaster), polymorphism in the length of microsatellite DNA within the regulatory region of the gene ( avpr1a) encoding the V1aR predicts differences among males in neural expression of V1aRs and partner preference under laboratory conditions. However, understanding the extent to which V1aR mediates variation in prairie vole social and reproductive behaviour observed in nature requires investigating the consequences of avpr1a polymorphism and environmental influences under ecologically relevant conditions. We examined the relationship between avpr1a length polymorphism and monogamy among male prairie voles living in 0.1 ha enclosures during a time similar to their natural lifespan. We found no evidence that avpr1a genotype of males predicts variation in social monogamy measured in the field but some indices of social monogamy were affected by population density. Parentage data indicated that a male’s avpr1a genotype significantly influenced the number of females with which he sired offspring and the total number of offspring sired. Total brain concentrations of V1aR mRNA were not associated with either male behaviour or avpr1a genotype. These data show that melding ecological field studies with neurogenetics can substantially augment our understanding of the effects of genes and environment on social behaviours. [ABSTRACT FROM AUTHOR]

Sperm competition theory predicts that colonially breeding birds, such as many seabirds, should be exposed to high risks of sperm competition because there are many potential mating partners and severe socioecological constraints on mate-guarding behaviour. However, parentage studies have usually revealed a low frequency of extrapair paternity in colonial seabirds. Detailed studies of copulation behaviour could provide valuable insights into the causality of genetic monogamy in these species. We investigated the timing, frequency and success of extrapair and within-pair copulation attempts in the little auk, a socially monogamous and highly colonial seabird that raises only a single chick per year. We found that the majority of monitored individuals (above 60% in both sexes) engaged in extrapair copulation activities. Extrapair copulation attempts made up usually more than 10% of all copulation attempts of a particular individual but were generally unsuccessful because of female rejection behaviour. Only 2% (8/330) of all copulations with cloacal contact were extrapair copulations. Molecular parentage analysis of 64 chicks revealed only two cases of extrapair paternity, which is comparable to the proportion of successful copulations that were extrapair. We conclude that genetic monogamy seems to be maintained at a proximate level through female resistance to male extrapair copulation attempts and frequent within-pair copulations. Nevertheless, not all extrapair copulations were rejected by females, which suggests that engaging in one or a few extrapair copulations could be adaptive to females, for example as an insurance against mate infertility. [Copyright &y& Elsevier]

The article presents a study which examines the rate of extra-pair paternity (EPP) in the Atlantic Puffin Fratercula arctica. It mentions that researchers collected blood and tissues from 12 and 26 different family groups of Atlantic Puffins in late June and early July of 2003 and 2004. It cites that blood from chicks and adults was sampled by puncturing the bird's metatarsus vein with a sterile needle wherein the sample was transferred and dissolved in one milliliter of Queen's lysis buffer. The study reveals that molecular sexing confirmed that all 34 pairs where both adults were sampled consisted of one male and one female. Moreover, researchers determined that the chick being studied was also sired by its putative father.

Animals often face trade-offs during reproduction between activities such as parental care and territory defence. In species that are socially monogamous, males and females are faced with the additional problem of coordinating their respective contributions to such activities. Here, we examined male incubation behaviour in a passerine that shows genetic monogamy and in which males incubate extensively. Male incubation is rare in North American passerines and little is known about how males defend their territories during the incubation stage and whether females compensate for lower male incubation during territorial intrusions. Blue-headed vireo males contribute 50% of incubation time during the day. We performed playbacks to simulate intrusions to males while they were on the nest and off the nest during the incubation period. On average, males took 18min to arrive at the playback location while on the nest incubating, but took less than 2min when not incubating. In addition, only 44% of the males sang while on the nest, whereas all males sang in response to the playback when off the nest. This result suggests that males probably delay territory defence until females return to the nest to avoid exposing the nest to predators. Females returned to the nest to relieve their mates from incubation duties sooner during experimental intrusions than during control periods, which also allowed males to pursue intruders sooner. Genetic monogamy may underlie this apparent cooperation and the sex-role convergence exemplified in this species. [Copyright &y& Elsevier]

There is growing interest in the mating systems of sharks and their relatives (Class Chondrichthyes) because these ancient fishes occupy a key position in vertebrate phylogeny and are increasingly in need of conservation due to widespread overexploitation. Based on precious few genetic and field observational studies, current speculation is that polyandrous mating strategies and multiple paternity may be common in sharks as they are in most other vertebrates. Here, we test this hypothesis by examining the genetic mating system of the bonnethead shark, Sphyrna tiburo, using microsatellite DNA profiling of 22 litters (22 mothers, 188 embryos genotyped at four polymorphic loci) obtained from multiple locations along the west coast of Florida. Contrary to expectations based on the ability of female S. tiburo to store sperm, the social nature of this species and the 100% multiple paternity observed in two other coastal shark species, over 81% of sampled bonnethead females produced litters sired by a single male (i.e. genetic monogamy). When multiple paternity occurred in S. tiburo, there was an indication of increased incidence in larger mothers with bigger litters. Our data suggest that sharks may exhibit complex genetic mating systems with a high degree of interspecific variability, and as a result some species may be more susceptible to loss of genetic variation in the face of escalating fishing pressure. Based on these findings, we suggest that knowledge of elasmobranch mating systems should be an important component of conservation and management programmes for these heavily exploited species. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ornithology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Ornithology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Demographic data from an 8-year study of a marked population showed that switching territories and mates is common in both genders of dusky antbirds (Cercomacra tyrannina), a sedentary neotropical passerine with year-round territories and pairbonds. We conducted 22 experimental removals and followed six natural disappearances to examine territory switching. Antbirds quickly abandoned territories and mates to move to openings created by experimental removals. Pairing with the resident on a new territory was rapid. Unmated birds attracted new mates by singing a gender-specific song that differed from songs given by mated birds. There were no gender differences in replacement time or rate. Some vacancies, experimental and natural, were not filled, suggesting that floaters were rare. Territory and mate switching were not related to immediate enhancement of reproductive success because the probability of reproducing successfully was equally poor on all territories. Territory switching may be an overlooked but common tropical form of territoriality that increases individual survivorship during periods of low food abundance (dry season). We suggest that switching is favored when low annual reproductive success enhances selection for a long lifespan as the primary means to increase reproductive success. [ABSTRACT FROM PUBLISHER]

Extensive behavioural and pedigree data on a colour-marked population of Florida scrub-jays ( Aphelocoma coerulescens) suggested that this cooperatively breeding species is monogamous, with extremely rare exceptions in which males have two mates. We used multi-locus DNA fingerprinting to test these observations by determining genetic parentage. Despite restricted dispersal and high relatedness between behavioural parents and non-breeding members of the group, DNA fingerprints provided sufficient variability to determine parentage unambiguously in almost all cases. We found no evidence of extra-pair fertilisation of females or egg dumping, and confirmed a suspected case of polygyny in which a mother and daughter laid and incubated in the same nest. Our results confirm that detailed behavioural data allow accurate assignment of genetic parentage in this species. In Florida scrub-jays, large territory size may limit opportunities for cuckoldry, and persistent intense competition for limited breeding space may lead to low variance in the quality of established male breeders. These factors would reduce both the opportunity for, and benefits of engaging in extra-pair fertilisations. Delayed dispersal and cooperative breeding in this species have not evolved as avenues for direct reproduction by unpaired individuals. [ABSTRACT FROM AUTHOR]

Based on the breeding synchrony hypothesis, we predicted, in two congeners that nest in simiilar habitat but differ in nesting synchrony, that blue-headed vireos (Vireo solitarius) would have fewer extrapair fertilizations (EPFs) thaii red-eyed vireos (V. olivaceus EPFs were rare in blue-headed vireos (1/37 nestlings), but common in red-eyed vireos (11/19 nestlings). We studied the behavior of blue-headed vireos to determine what factors could promote genetic monogamy. We found no evidence that males mate guarded to prevent extrapair copulations from occurring. Males did not follow fertile mates closely when mates left the nest (14–25% of female departures) and, during the egg-laying period, males were often alone on the nest (22.3 mm/h). Female blue-headed vireos, but not red-eyed vireos, obtain direct benefits from social mates such as nest building and incubation (49.1% of the total), and they assess male quality long before becoming fertile. Female blue-headed vireos spent more time incubating when their mates had low incubation effort. Furthermore, male incubation effort was positively correlated with nest survival during incubation. We discuss the evolution of genetic monogamy and sex role convergence in blue-headed vireos in relation to asynchronous breeding. [ABSTRACT FROM AUTHOR]

Competing Interests: Conflict of Interest: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Monogamy is a rare strategy among mammals but relatively common among primates. The study of the evolution of monogamy in mammals and primates is lacking empirical studies that assess the relationship between a pair‐living social organization and genetic monogamy. Sexual or genetic monogamy can only be assessed by performing molecular analyses and investigating rates of extra‐pair paternity (EPP). Studying the occurrence of EPP can provide valuable insights into reproductive strategies and their adaptive value. The indri is a pair‐living primate that lives in stable groups. Their social units are composed of the reproductive pair and up to four more individuals, but extra‐pair copulation (EPC) can occur. This raises the question of whether this event may or may not lead to EPP. Here, we investigated whether a pair‐living social organization corresponds to genetic monogamy in indris (Indri indri). We analyzed the paternity of 12 offspring from seven pairs using a set of six microsatellite loci on fecal samples (mean number of alleles 11.7 ± 1.8 (mean ± standard deviation). We found that in 92% of cases the genetic profile of the offspring matched the paired male of the group for all the loci considered. In the only case of paternity mismatch, the paternity assignment remained inconclusive. Our results show that I. indri genetic monogamy is the norm and supports the hypothesis that pair‐living social organization is associated with low EPP rate. Also, our results are in contrast with the hypothesis of infertility as a reason to engage in EPC for this species. HIGHLIGHTS: In 92% of cases, the paired male of the group did not have any locus mismatch with the offspring. In the only case of paternity mismatch, we were not able to assign the sire identity.Our finding suggests that genetic monogamy is the norm in the indri, although EPC can occasionally occur. [ABSTRACT FROM AUTHOR]