Isolation and characterization of highly polymorphic microsatellite loci in the 2‐Spot Ladybird,Adalia bipunctata

Contrary to theoretical predictions, female 2‐spot ladybirds (Adalia bipunctata) mate many more times than necessary to maintain high fertilisation success and may gain through the acquisition of material or genetic benefits. In order to investigate this mating system in detail, microsatellite markers have been isolated using a modified enrichment technique. Thirty‐nine loci were successfully amplified by polymerase chain reaction (PCR), of which only two were monomorphic. Detailed characterization of ten loci revealed very high levels of polymorphism. These markers are likely to be invaluable tools with which to study population genetics and patterns of paternity in this species.     

Validation of density–elasticity relationships for finite element modeling of human pelvic bone by modal analysis

In total hip arthroplasty and particularly in revision surgery, computer assisted pre-operative prediction of the best possible anchorage strategy for implant fixation would be a great help to the surgeon. Computer simulation relies on validated numerical models. In the current study, three density–elasticity relationships (No. 1–3) from the literature for inhomogeneous material parameter assignment from CT data in automated finite element (FE) modeling of long bones were evaluated for their suitability for FE modeling of human pelvic bone. Numerical modal analysis was conducted on 10 FE models of hemipelvic bone specimens and compared to the gold standard provided by experimental modal analysis results from a previous in-vitro study on the same specimens. Overall, calculated resonance frequencies came out lower than measured values. Magnitude of mean relative deviation of numerical resonance frequencies with regard to measured values is lowest for the density–elasticity relationship No. 3 (−15.9%) and considerably higher for both density–elasticity relationships No. 1 (−41.1%) and No. 2 (−45.0%). Mean MAC values over all specimens amount to 77.8% (No. 1), 78.5% (No. 2), and 83.0% (No. 3). MAC results show, that mode shapes are only slightly influenced by material distribution. Calculated resonance frequencies are generally lower than measured values, which indicates, that numerical models lack stiffness. Even when using the best suited (No. 3) out of three investigated density–elasticity relationships, in FE modeling of pelvic bone a considerable underestimation of model stiffness has to be taken into account.     

The messenger matters: Pollinator functional group influences mating system dynamics

The incredible diversity of plant mating systems has fuelled research in evolutionary biology for over a century. Currently, there is broad concern about the impact of rapidly changing pollinator communities on plant populations. Very few studies, however, examine patterns and mechanisms associated with multiple paternity from cross‐pollen loads. Often, foraging pollinators collect a mixed pollen load that may result in the deposition of pollen from different sires to receptive stigmas. Coincident deposition of self‐ and cross‐pollen leads to interesting mating system dynamics and has been investigated in numerous species. But, mixed pollen loads often consist of a diversity of cross‐pollen and result in multiple sires of seeds within a fruit. In this issue of Molecular Ecology, Rhodes, Fant, and Skogen ( 2017 ) examine how pollinator identity and spatial isolation influence multiple paternity within fruits of a self‐incompatible evening primrose. The authors demonstrate that pollen pool diversity varies between two pollinator types, hawkmoths and diurnal solitary bees. Further, progeny from more isolated plants were less likely to have multiple sires regardless of the pollinator type. Moving forward, studies of mating system dynamics should consider the implications of multiple paternity and move beyond the self‐ and cross‐pollination paradigm. Rhodes et al. ( 2017 ) demonstrate the importance of understanding the roles that functionally diverse pollinators play in mating system dynamics.     

distruct: a program for the graphical display of population structure

In analysis of multilocus genotypes from structured populations, individual coefficients of membership in subpopulations are often estimated using programs such as structure . distruct provides a general method for visualizing these estimated membership coefficients. Subpopulations are represented as colours, and individuals are depicted as bars partitioned into coloured segments that correspond to membership coefficients in the subgroups. distruct , available at http://www.cmb.usc.edu/~noahr/distruct.html , can also be used to display subpopulation assignment probabilities when individuals are assumed to have ancestry in only one group.     

Mate choice in modern societies

Most research on mate choice in modern societies is based on data that may or may not reflect actual mating behavior (e.g., stated preferences, personal advertisements). In the present study, real-life matings were reported by a large representative sample of men and women (N = 1,133). These data were used to test an evolutionary model in which mate choice is hypothesized to depend on resources potentially contributed to reproduction by each sex. Consistent with the model, it was found that (a) men (but not women) of higher social status acquire more mating partners, suggesting that male status is an important criterion in female choice; (b) women’s (but not men’s) number of partners decreases linearly with age, suggesting that female reproductive potential is an important criterion in male choice; and (c) women (but not men) display a significant relationship between marital dissolution and promiscuity, suggesting that female sexual exclusivity is an important criterion in male choice. These results are discussed in relation to understanding mate choice mechanisms from behavioral data. Daniel Pérusse is an assistant professor in the Department of Anthropology at the Université de Montréal. His research interests include the evolutionary biology of human social and reproductive behavior, sexual selection theory, and biocultural evolution. His current research bears on human socialization processes and psychosocial development from an evolutionary and behavior-genetic perspective. Recent publications include “Cultural and Reproductive Success in Industrial Societies: Testing the Relationship at the Proximate and Ultimate Levels” (Behavioral and Brain Sciences 16(2):267–322, 1993) and “Human Parental Behavior: Evidence for Genetic Influence and Potential Implications for Gene-Culture Theory” with M. C. Neale, A. Heath, and L. J. Eaves (Behavior Genetics, in press).     

Does paternity or paternal investment determine the level of paternal care and does female choice explain egg stealing in the fifteen-spined stickleback?

An earlier field study on the fifteen-spined stickleback (Spinachia spinachia) showed that frequent male—male interactionsresult in high frequencies of sneaking and egg stealing. Moreover,sneaking behavior was performed not only by males adoptingalternative mating strategies, but also by males with theirown nests. The advantage of sneaking is easily understood, but it is more difficult to explain the evolutionary benefitof stealing eggs from other males. I investigated whether malessuffering from sneaking adjust their paternal effort in relationto their degree of paternity. I also examined whether femalesprefer males that have more eggs in their nests, as this couldexplain egg stealing. There was no relationship between thedegree of paternity and fanning activity, hatching success,or nest defense. However, the older the eggs become, the morethe males increase their attack rate toward potential egg predators(goldsinny wrasse and shore crabs). Thus, males adjusted theirlevel of defense to the amount of energy and time already investedin the clutch. Females did not prefer males with more eggs intheir nests. On the contrary, females preferred males withreduced clutches over males with enlarged clutches. Therefore,female choice is unlikely to be a driving force behind eggstealing in this species.     

A Simple Numerical Procedure for Estimating the Prior Probability in the Biomathematical Proof of Paternity

This note gives a simple procedure for finding the maximum likelihood estimate of the prior probabilities in paternity cases. The procedure is based on a fixed point principle.     

DNA profiling of cattle using micro- and minisatellite core probes

We have evaluated 15 different micro- and minisatellite core probes for use in identity and paternity testing in cattle, based on Southern blot hybridization analysis. The core probes were tested in animals of different breeds and by analysis of seven two-generation pedigrees. Of the 15 core probes tested, seven were able to detect on average seven variant bands per individual animal. Segregation analysis showed that on average two out of 3 6 variant bands scored per core probe were genetically linked while two out of 12 variant bands correspond to the same allelic pair. The results obtained demonstrate the effectiveness of multilocus core probes for determining identity and paternity in cattle.     

Male mating success in an aquatically mating pinniped, the harbour seal (Phoca vitulina), assessed by microsatellite DNA markers

Similar to many other pinniped species, harbour seals ( Phoca vitulina ) mate exclusively at sea. Here we present the first attempt to measure male mating success in an aquatically mating pinniped. Male mating success was estimated by paternity analysis in two cohorts of pups born at Sable Island, Nova Scotia, Canada, using microsatellite DNA markers. The genotypes of 275 pups born in 1994 and 1995 were compared to those of 90 candidate males at six microsatellite loci using a likelihood approach to resolve paternity. Paternity could be assigned for two, 22, 40 and 85 pups at confidence levels of 95, 80, 65 and 50%, respectively. Most successful males were assigned the paternity of a single offspring, suggesting a low variance in male mating success relative to most pinniped species. The proportion of paternal half sibs within cohorts and between maternally related sibs estimated by maximum likelihood were not significantly different from zero. It is thus unlikely that most offspring were sired by a small number of highly successful unsampled males, and that female harbour seals do not usually exhibit fidelity to the same male in sequential breeding seasons. A low level of polygyny in Sable Island harbour seals is consistent with predictions based on their breeding ecology, as females are highly mobile and widely dispersed in the aquatic mating environment at Sable Island.     

Fractional paternity assignment: theoretical development and comparison to other methods

Summary There has recently been a burgeoning interest in the analysis of paternity patterns for natural populations because of its relevance to population genetic phenomena such as the distance between successful mates, relative male reproductive success and gene flow. In this paper we develop a method of analyzing populational patterns of paternity, the fractional paternity method, and compare its performance to two other commonly used methods of paternity analysis (simple exclusion and the most-likely methods). We show that the fractional method is the most accurate method for determining populational patterns of paternity because it assigns paternity to all progeny examined, and because it avoids biases inherent in the other paternity analysis methods when model assumptions are met. In particular, it avoids a systematic bias of the most-likely paternity assignment method, which has a tendency to over-assign paternity of progeny to certain male parents with a greater than average number of homozygous marker loci. We also demonstrate the effect of linkage of some of the marker loci on paternity assignment, showing how the knowledge of the linkage phase of male and female parents in the population can significantly improve the accuracy of the estimates of populational patterns of paternity. Knowledge of the linkage phase of individuals in a population is usually unknown and difficult to assess without progeny testing, which involves considerable labor. However, we show how the linkage phase of hermaphroditic individuals in a population can be obtained in conjunction with the paternity analysis if progeny can be obtained from each hermaphroditic individual in the population, thereby avoiding the problem of traditional progeny testing. Applications of the fractional paternity approach developed herein should contribute significantly to our understanding of the mating patterns in, and hence the evolution of, natural populations.