Multiple Fathers Research Articles

Mating frequency estimation and its importance for colony abundance analyses in eusocial pollinators: a case study of Bombus impatiens (Hymenoptera: Apidae).

The genus Bombus (bumble bees) includes approximately 265 species, many of which are in decline in North America and Europe. To estimate colony abundance of bumble bees in natural and agricultural habitats, sibship relationships are often reconstructed from genetic data with the assumption that colonies have 1 monandrous queen. However, some species such as the North American common eastern bumble bee (Bombus impatiens Cresson) can display low levels of polyandry, which may bias estimates of colony abundance based on monandrous sibship reconstructions. To accurately quantify rates of polyandry in wild and commercially mated queens of this species, we empirically estimated mating frequencies using a novel statistical model and genotypes from 730 bees. To genotype individuals, we used a highly polymorphic set of microsatellites on colonies established from 20 wild-caught gynes and 10 commercial colonies. We found multiple fathers in 3 of the wild colonies and 3 of the commercial colonies. This resulted in average effective mating frequencies of 1.075 ± 0.18 and 1.154 ± 0.25 for wild and commercial colonies, respectively. These findings agree with previous reports of low rates of polyandry for B. impatiens. Using a large empirical dataset, we demonstrate that assuming monandry for colony abundance estimation in species that violate this assumption results in an overestimation of the number of colonies. Our results emphasize the importance of studying mating frequencies in social species of conservation concern and economic importance for the accuracy of colony abundance estimation and for understanding their ecology and sociobiology.

Social and genetic relationships among individuals in urban kit fox social groups

Smaller canids, such as most foxes, individually hunt small prey, and therefore, social groups typically consist of just a mated pair. However, these smaller canids occasionally form groups in which the members have been presumed to be genetically or socially related. We studied social and genetic relationships among urban San Joaquin kit fox ( Vulpes macrotis mutica Merriam, 1902) groups in Bakersfield, California. Of 59 groups, 42.4% had extra adults in addition to the parents. Foxes were field classified as either mothers, fathers, helpers (extra adults), or pups. We then assessed relatedness of foxes within social groups using 11 microsatellites in DNA from tissue or hair samples. Mated pairs were significantly less related than mothers and helpers, with fathers and helpers being intermediate. Twelve pairs of females were mother–daughter dyads, but we also found two cases of sisters and two cases where the females were unrelated. Pups were always related to a female identified as their mother. Father–pup pairs were less related than mother–pup pairs, with helper–pup pairs being intermediate. The extra-pair paternity rate (multiple fathers per litter) was 39%. The social flexibility exhibited by kit foxes may increase their resiliency to marked fluctuations in resource availability, thereby reducing extinction risk.

Polyandry and sperm competition in two traumatically inseminating species of Strepsiptera (Insecta)

Polyandry, the practice of females mating with multiple males, is a strategy found in many insect groups. Whether it increases the likelihood of receiving beneficial genes from male partners and other potential benefits for females is controversial. Strepsiptera are generally considered monandrous, but in a few species females have been observed copulating serially with multiple males. Here we show that the offspring of a single female can have multiple fathers in two Strepsiptera species: Stylops ovinae (Stylopidae) and Xenos vesparum (Xenidae). We studied female polyandry in natural populations of these two species by analysis of polymorphic microsatellite loci. Our results showed that several fathers can be involved in both species, in some cases up to four. Mating experiments with S. ovinae have shown that the first male to mates with a given female contributes to a higher percentage of the offspring than subsequent males. In X. vesparum, however, we found no significant correlation between mating duration and offspring contribution. The prolonged copulation observed in S. ovinae may have the advantage of reducing competition with sperm from other males. Our results show that monandry may not be the general pattern of reproduction in the insect order Strepsiptera.

In the intimacy of the darkness: Genetic polyandry in deep-sea luminescent lanternsharks Etmopterus spinax and Etmopterus molleri (Squaliformes, Etmopteridae).

Multiple paternity seems common within elasmobranchs. Focusing on two deep-sea shark species, the velvet belly lanternshark (Etmopterus spinax) and the slendertail lanternshark (Etmopterus molleri) we inferred the paternity in 31 E. spinax litters from Norway (three to 18 embryos per litter) and six E. molleri litters from Japan (three to six embryos), using 21 and 10 specific microsatellites, respectively. At least two E. spinax litters were sired from multiple fathers each, with highly variable paternal skew (1:1 to 9:1). Conversely, no clear signal of genetic polyandry was found in E. molleri.

A comparison of methodologies: sibling identification using a relational versus a graph-based approach

IntroductionThe detection of siblings is an important pre-requisite for many research problems, yet is traditionally difficult or time-consuming owing to the way linked data is conventionally stored. We compare the methodology and results for an identification of siblings by SANT DataLink using a legacy relational approach and a graph-based approach.
 Objectives and ApproachAn existing project involving the identification of sibling clusters using relational techniques was replicated using the same core data in SANT DataLink’s Next Generation Linkage Managment System (NGLMS) which is graph-based. Data is stored in the NGLMS using richer relationships than just 'is W% similar to' or 'is part of group N'. Birth data was separated into children and parents and explicit child/parent relationships recorded. When coupled with electoral roll data using probabilistic and deterministic linkage, sibling structure can be identified by performing network traversal via parents, e.g.
 crecord—[MOTHER]⟶mrecord—[IS_SIMILAR_TO]⟶mrecord*⟵[MOTHER]—crecord*
 i.e. find the mother, find that mother’s cluster, find all children related to that cluster. The resulting records are siblings.
 ResultsA graph-based approach enabled the methology of 'finding siblings' to be more clearly described and communicated by mirroring genealogical structures natively within in the data. Comparable results were achieved in a shorter time with less manual effort using the same underlying data. Generating sibling clusters from the graph-based data required less manual intervention and review as explicit PARENT/CHILD relationships were stored in the data and able to be quickly traversed to assemble familial units and thus siblings. A focus on automated linkage quality rather than manual review was facilitated by the approach. Anomalous structures requiring detailed review, such as multiple fathers and mothers of a single child, were trivially identifiable and so manual effort was focussed on actions where a higher return in terms of end-product quality could be achieved.
 Conclusion/ImplicationsStoring data in a representation which more closely resembles the the underlying real-world situation allows greater fidelity with respect to data modeling. This in turn, enables the asking of richer questions and makes the answering of such questions much easier.

Mate guarding and male body condition shape male fertilization success and female mating system in the common quail

In species with female polygamy, pair bonds are frequently established since mate guarding can determine male fertilization success. However, extending the duration of pair bonds also implies reducing the chances of finding new mates. Males face a trade-off between mate guarding and looking for new mates, which can be shaped by their body condition. Here, we investigated the effect of male body condition and mate guarding over the female mating system (genetic monogamy or polygamy) and the male fertilization success in the common quail, Coturnix coturnix, a species with sperm storage and thus the potential for postcopulatory selection, and without paternal care. We monitored 20 females and 32 males. We genotyped them, the 21 clutches laid by these females and a large proportion of the males present in the population, which could have sired the clutches, to perform paternity analyses. We tested whether it is the pairing order or the duration of the pair bond that determines the fertilization outcome in clutches with multiple fathers. We hypothesized that males with better body condition might be able to find a mate faster, reducing the cost of mate switching and increasing fertilization success by spending less time in a pair bond. We observed socially monogamous and polygamous females, and our genetic analyses revealed that broods could be sired by one and by multiple fathers. Female genetic polygamy was more frequent when first matings were with males in good body condition. We detected two or three different fathers in multiple paternity broods. The male that mate guarded for longest was the one that sired most of the clutch. Although males in better body condition seemed to establish shorter pair bonds, further data are needed to confirm this trend.

A Review of Patterns of Multiple Paternity Across Sea Turtle Rookeries.

Why females would mate with multiple partners and have multiple fathers for clutches or litters is a long-standing enigma. There is a broad dichotomy in hypotheses ranging from polyandry having benefits to simply being an unavoidable consequence of a high incidence of male-female encounters. If females simply give in to mating when it is too costly to avoid being harassed by males (convenience polyandry), then there should be a higher rate of mating as density increases. However, if females actively seek males because they benefit from multiple mating, then mating frequency, and consequently the incidence of multiple paternity of clutches, should be high throughout. To explore these competing explanations, here we review the incidence of multiple paternity for sea turtles nesting around the World. Across 30 rookeries, including all 7 species of sea turtle, the incidence of multiple paternity was only weakly linked to rookery size (r2=0.14). However, using high resolution at-sea GPS tracking we show that the specifics of movement patterns play a key role in driving packing density and hence the likely rate of male-female encounters. When individuals use the same focal areas, packing density could be 100× greater than when assuming individuals move independently. Once the extent of adult movements in the breeding season was considered so that movements and abundance could be combined to produce a measure of density, then across rookeries we found a very tight relationship (r2=0.96) between packing density and the incidence of multiple paternity. These findings suggest that multiple paternity in sea turtles may have no benefit, but is simply a consequence of the incidence of male-female encounters.

Variability in Parenting Self-Efficacy Across Prudential Adolescent Behaviors

SYNOPSISObjective. Extant research examining the predictors and outcomes of parenting self-efficacy has predominantly focused on families with young children. Adolescence is a time of increased autonomy during which parents may be uncertain about their abilities to influence their adolescents’ risk-taking behavior. Design. Parents’ (N = 145 mothers and 53 fathers) confidence in their parenting abilities across prudential adolescent behaviors was investigated, including alcohol consumption, cyber activities, eating behaviors, and problem peer associations. Additionally, we explored how adolescents’ (N = 161, Mage = 14.4 years, 60% female) reports of their engagement in those behaviors were associated with parents’ perceptions of their ability to impact their adolescents’ behavior (i.e., self-efficacy). Results. Mixed-model analysis of variance revealed that mothers and fathers felt most efficacious in reducing their adolescents’ engagement in problematic cyber activities and least efficacious regarding alcohol consumption. Bivariate correlations indicated multiple negative associations between adolescents’ engagement in prudential behaviors and both mothers’ and fathers’ behavior-specific parenting self-efficacy. Conclusions. Results suggest that parents with adolescents have varying levels of confidence in their ability to parent different types of prudential adolescent behaviors. Additionally, for multiple behavior categories, mothers’ and fathers’ behavior-specific parenting self-efficacy was negatively associated with adolescent engagement in corresponding behaviors, such that increased adolescent engagement was related to lower levels of behavior-specific parenting self-efficacy.

Increase in multiple paternity across the reproductive lifespan in a sperm-storing, hermaphroditic freshwater snail.

Polyandry is a common phenomenon and challenges the traditional view of stronger sexual selection in males than in females. In simultaneous hermaphrodites, the physical proximity of both sex functions was long thought to preclude the operation of sexual selection. Laboratory studies suggest that multiple mating and polyandry in hermaphrodites may actually be common, but data from natural populations are sparse. We therefore estimated the rate of multiple paternity and its seasonal variability in the annual, sperm-storing, simultaneously hermaphroditic freshwater snail Radix balthica for the entire duration of the reproductive lifespan. We also tested whether multiple paternity was associated with clutch size or embryonic development. To obtain these data, we measured and genotyped 60 field-collected egg clutches using nine highly polymorphic microsatellite markers. Overall, 50% of the clutches had multiple fathers, and both the frequency (20-93% of clutches) and magnitude of multiple paternity (mean 1.3-3.8 fathers per clutch) substantially increased over time, probably because of extensive sperm storage. Most multiply sired clutches (83%) had a dominant father, but neither clutch size nor the proportion of developed embryos per clutch was associated with levels of multiple paternity. Both the evident promiscuity and the frequent skew of paternity shares suggest that sexual selection may be an important evolutionary force in the study population.

An optimized approach for massive web page classification using entity similarity based on semantic network

With the development of mobile technology, the users browsing habits are gradually shifted from only information retrieval to active recommendation. The classification mapping algorithm between users interests and web contents has been become more and more difficult with the volume and variety of web pages. Some big news portal sites and social media companies hire more editors to label these new concepts and words, and use the computing servers with larger memory to deal with the massive document classification, based on traditional supervised or semi-supervised machine learning methods. This paper provides an optimized classification algorithm for massive web page classification using semantic networks, such as Wikipedia, WordNet. In this paper, we used Wikipedia data set and initialized a few category entity words as class words. A weight estimation algorithm based on the depth and breadth of Wikipedia network is used to calculate the class weight of all Wikipedia Entity Words. A kinship-relation association based on content similarity of entity was therefore suggested optimizing the unbalance problem when a category node inherited the probability from multiple fathers. The keywords in the web page are extracted from the title and the main text using N-gram with Wikipedia Entity Words, and Bayesian classifier is used to estimate the page class probability. Experimental results showed that the proposed method obtained good scalability, robustness and reliability for massive web pages.

Does multiple paternity affect seed mass in angiosperms? An experimental test in Dalechampia scandens.

Flowers fertilized by multiple fathers may be expected to produce heavier seeds than those fertilized by a single father. However, the adaptive mechanisms leading to such differences remain unclear, and the evidence inconsistent. Here, we first review the different hypotheses predicting an increase in seed mass when multiple paternity occurs. We show that distinguishing between these hypotheses requires information about average seed mass, but also about within-fruit variance in seed mass, bias in siring success among pollen donors, and whether siring success and seed mass are correlated. We then report the results of an experiment on Dalechampia scandens (Euphorbiaceae), assessing these critical variables in conjunction with a comparison of seed mass resulting from crosses with single vs. multiple pollen donors. Siring success differed among males when competing for fertilization, but average seed mass was not affected by the number of fathers. Furthermore, paternal identity explained only 3.8% of the variance in seed mass, and siring success was not correlated with the mass of the seeds produced. Finally, within-infructescence variance in seed mass was not affected by the number of fathers. These results suggest that neither differential allocation nor sibling rivalry has any effect on the average mass of seeds in multiply sired fruits in D.scandens. Overall, the limited paternal effects observed in most studies and the possibility of diversification bet hedging among flowers (but not within flowers), suggest that multiple paternity within fruits or infructescence is unlikely to affect seed mass in a large number of angiosperm species.

Co-father relationships among the Suruí (Paiter) of Brazil.

Partible paternity refers to the conception belief that children can have multiple fathers (“co-fathers”) and is common to indigenous cultures of lowland South America. The nature of social relationships observed between co-fathers reveals information about the reproductive strategies underlying partible paternity. Here we analyze clan, genealogical, and social relationships between co-fathers for the Suruí, an indigenous horticultural population in Brazil. We show that co-fathers roughly assort into two separate categories. In the affiliative category, co-father relationships are amicable when they are between close kin, namely brothers and father-son. In the competitive category, relationships are more likely of avoidance or open hostility when between more distant kin such as cousins or unrelated men of different clans. Results therefore imply multiple types of relationships, including both cooperative and competitive contexts, under the rubric of partible paternity. These complexities of partible paternity institutions add to our knowledge of the full range of cross-cultural variation in human mating/marriage arrangements and speak to the debate on whether or not humans should be classified as cooperative breeders.

Strong male-biased operational sex ratio in a breeding population of loggerhead turtles (Caretta caretta) inferred by paternal genotype reconstruction analysis.

Characterization of a species mating systems is fundamental for understanding the natural history and evolution of that species. Polyandry can result in the multiple paternity of progeny arrays. The only previous study of the loggerhead turtle (Caretta caretta) in the USA showed that within the large peninsular Florida subpopulation, multiple paternity occurs in approximately 30% of clutches. Our study tested clutches from the smaller northern subpopulation for the presence of multiple paternal contributions. We examined mothers and up to 20 offspring from 19.5% of clutches laid across three nesting seasons (2008–2010) on the small nesting beach on Wassaw Island, Georgia, USA. We found that 75% of clutches sampled had multiple fathers with an average of 2.65 fathers per nest (1–7 fathers found). The average number of fathers per clutch varied among years and increased with female size. There was no relationship between number of fathers and hatching success. Finally, we found 195 individual paternal genotypes and determined that each male contributed to no more than a single clutch over the 3-year sampling period. Together these results suggest that the operational sex ratio is male-biased at this site.

The secret sex lives of sage-grouse: multiple paternity and intraspecific nest parasitism revealed through genetic analysis

In lek-based mating systems only a few males are expected to obtain the majority of matings in a single breeding season and multiple mating is believed to be rare. We used 13 microsatellites to genotype greater sage-grouse (Centrocercus urophasianus) samples from 604 adults and 1206 offspring from 191 clutches (1999–2006) from Alberta, Canada, to determine paternity and polygamy (males and females mating with multiple individuals). We found that most clutches had a single father and mother, but there was evidence of multiple paternity and intraspecific nest parasitism. Annually, most males fathered only one brood, very few males fathered multiple broods, and the proportion of all sampled males in the population fathering offspring averaged 45.9%, suggesting that more males breed in Alberta than previously reported for the species. Twenty-six eggs (2.2%) could be traced to intraspecific nest parasitism and 15 of 191 clutches (7.9%) had multiple fathers. These new insights have important implications on what we know about sexual selection and the mating structure of lekking species. Key wor ds: lek, multiple paternity, nest parasitism, paternity, polygyny, sage-grouse. [Behav Ecol]

The Participation of Fathers in Child Protection Conferences: A Practitioner's Perspective

Fathers’ involvement in child protection processes appears to remain low and is problematic given their influence over the lives and wellbeing of their children and partners. Men's views need to be taken into account, as part of consideration of risk and the meaning of their participation for others in the family. While the risk or presence of abuse may necessarily limit how the participation of a father is managed in case conferences, and needs to be explored and challenged, in most cases it does not justify failing to contact or seeking to involve fathers. Involving fathers is crucial to actively managing and tackling risks. Most work on engaging fathers has been focused on engaging them one‐to‐one or in families. This article focuses on the neglected issue of the participation of fathers in child protection conferences and subsequent inter‐agency team work on the child protection plan recommended at the child protection conference. It argues that, with careful preparation and chairing, fathers’ participation can be managed using the skills of relationship‐based and authoritative practice in tandem. Copyright © 2012 John Wiley & Sons, Ltd.‘Fathers’ involvement in child protection processes appears to remain low’‘Fathers’ participation can be managed using the skills of relationship‐based and authoritative practice in tandem’Key Practitioner Messages Including fathers' participation and views should be a requirement of good practice and forms an integral part of the assessment and management of risks; the extent of live participation depends on, and needs to be limited to manage, the immediate risks. Even in complex cases involving multiple fathers, careful planning and skilled chairing can make it possible to include all the men in conferences. The energy and commitment that can be generated for fathers at conferences can be harnessed to help enable them to change.

High incidence of multiple paternity in an Australian snapping turtle (Elseya albagula)

Genetic parentage studies can provide detailed insights into the mating system dynamics of wild populations, including the prevalence and patterns of multiple paternity. Multiple paternity is assumed to be common among turtles, though its prevalence varies widely between species and populations. Several important groups remain to be investigated, including the family Chelidae, which dominate the freshwater turtle fauna of the Southern Hemisphere. We used seven polymorphic microsatellite markers to investigate the presence of multiple fathers within clutches from the white-throated snapping turtle (Elseya albagula), an Australian species of conservation concern. We uncovered a high incidence of multiple paternity, with 83% of clutches showing evidence of multiple fathers and up to three males contributing to single clutches. We confirm a largely promiscuous mating system for this species in the Burnett River, Queensland, although a lone incidence of single paternity indicates it is not the only strategy employed. These data provide the first example of multiple paternity in the Chelidae and extend our knowledge of the taxonomic breadth of multiple paternity in turtles of the Southern Hemisphere.

P2-S9.08 Baby daddy sex as a risk factor for HIV/STDs

BackgroundConcurrent sexual relationships increase the likelihood of exposure to HIV/STDs. Sexual patterns among poor urban African-American (AA) women may help to explain the disproportionate incidence of HIV/STDs seen in this...

Paternal genotype reconstruction reveals multiple paternity and sex ratios in a breeding population of leatherback turtles (Dermochelys coriacea)

When animals are difficult to observe while breeding, insights into the mating system may be gained by using molecular techniques. Patterns of extra-pair copulation, multiple paternity and parental genotype analysis may elucidate population characteristics that help improve knowledge of life history while informing management decisions. During the course of a long-term study of leatherback turtles, we assessed the level of multiple paternity in successive clutches for 12 known females nesting at Sandy Point National Wildlife Refuge (St. Croix, U.S. Virgin Islands). We used seven polymorphic microsatellite markers to genotype the females and 1,019 hatchlings representing 38 nests (3–4 clutches from each female). Using deductive genotype reconstruction and GERUD1.0, we identified the 12 mothers and 17 different fathers that were responsible for 38 nests. We found that seven females (58.3%) showed no evidence of multiple paternity in their clutches, while five females (41.7%) had mated with two males each. There was evidence of two fathers (polyandry) in successive clutches for these five females. Multiple fathers didn’t contribute to clutches equally. For clutches laid by an individual female, the primary father was responsible for 53.7 to 85.9% of the hatchlings. We demonstrate the feasibility of using male genotype reconstruction to characterize the male component of this breeding population and to assess operational sex ratios for breeding sea turtles.

Prevalence of multiple mating by female common dormice, Muscardinus avellanarius

Mating behaviour is an important component of species’ life histories. Knowledge of natural patterns of mating can lead also to more effective management strategies for populations of conservation concern. Despite a high conservation profile many aspects of the biology of the common dormouse (Muscardinus avellanarius) remain unknown, potentially limiting present conservation efforts. We determine the mating behaviour of M. avellanarius at two woodland sites in the UK: (1) Bontuchel (a natural population in Wales) and (2) Wych (a population in England that was established by reintroducing captive-bred animals) by genotyping mothers and litters at a panel of 10 microsatellite loci. Adult female body weight positively correlates with litter size and no apparent reproductive skew was evident. We found that multiple mating by female dormice is prevalent at both sites, with litters containing three or more offspring sired by multiple fathers; moreover, multiple mating is adopted by released animals even after a period of captive breeding where females are mated singly or as a breeding pair. We also present evidence for low proportion of fathers identified in our samples that probably related to unsampled individuals and/or larger than anticipated population sizes. This first report of mating behaviour in M. avellanarius highlights the role of genetic studies to uncover species’ reproductive behaviours and include these data for conservation management.

Evolutionary history of partible paternity in lowland South America

Partible paternity, the conception belief that more than one man can contribute to the formation of a fetus, is common in lowland South America and characterized by nonexclusive mating relationships and various institutionalized forms of recognition and investment by multiple cofathers. Previous work has emphasized the fitness benefits for women where partible paternity beliefs facilitate paternal investment from multiple men and may reduce the risk of infanticide. In this comparative study of 128 lowland South American societies, the prevalence of partible paternity beliefs may be as much as two times as common as biologically correct beliefs in singular paternity. Partible paternity beliefs are nearly ubiquitous in four large language families--Carib, Pano, Tupi, and Macro-Je. Phylogenetic reconstruction suggests that partible paternity evolved deep in Amazonian prehistory at the root of a tentative Je-Carib-Tupi clade. Partible paternity often occurs with uxorilocal postmarital residence (males transfer), although there are exceptions. Partible paternity may have benefits for both sexes, especially in societies where essentially all offspring are said to have multiple fathers. Despite a decrease in paternity certainty, at least some men probably benefit (or mitigate costs) by increasing their number of extramarital partners, using sexual access to their wives to formalize male alliances, and/or sharing paternity with close kin.