Multiple Paternity

We examined multiple paternity during eight breeding events within a 10-year period (1995–2005) for a total of 114 wild American alligator nests in Rockefeller Wildlife Refuge in south-west Louisiana. Our goals included examining (i) within population variation in multiple paternity among years, (ii) variation in multiple paternity in individual females and (iii) the potential for mate fidelity. To accomplish this, in the current study, eggs were sampled from 92 nests over 6 years and analysed along with 22 nests from a previous 2-year study. Genotypes at five microsatellite loci were generated for 1802 alligator hatchlings. Multiple paternity was found in 51% of clutches and paternal contributions to these clutches were highly skewed. Rates of multiple paternity varied widely among years and were consistently higher in the current study than previously reported for the same population. Larger females have larger clutches, but are not more likely to have multiply sired nests. However, small females are unlikely to have clutches with more than two sires. For 10 females, nests from multiple years were examined. Seven (70%) of these females exhibited long-term mate fidelity, with one female mating with the same male in 1997, 2002 and 2005. Five females exhibiting partial mate fidelity (71%) had at least one multiple paternity nest and thus mated with the same male, but not exclusively. These patterns of mate fidelity suggest a potential role for mate choice in alligators.

Proposed benefits of multiple paternity include increased reproductive output, elevated fitness of progeny, and maintenance of population genetic diversity. However, an alternative consideration is whether multiple paternity is simply an unavoidable byproduct of sexual conflict, with males seeking to maximize mating encounters while females seek to minimize the stress of copulation. Here we examine the polyandrous mating system in sharks, with a focus on the reproductive genetics of the shortspine spurdog, Squalus mitsukurii. Members of the genus Squalus are long-lived, slow-growing, and employ the longest gestation period of any vertebrate. To evaluate multiple paternity and genetic diversity in S. mitsukurii, we genotyped 27 litters plus 96 individuals with eight microsatellite loci. Further, 670 bp of the mtDNA control region were sequenced in 112 individuals to examine population structure. Squalus mitsukurii in Hawaii show low genetic diversity relative to other sharks (π = 0.0010 ± 0.0008) and no significant population structure in the Hawaiian Archipelago. Direct allele counts and Bayesian approximations returned concordant estimates of 11% multiple paternity, the lowest observed in sharks to date. Pearson correlation analysis of multiple paternity and heterozygosity in five shark studies reveals an R2 = 0.40. Though non-significant, these data indicate that multiple paternity may promote retention of genetic diversity. Considering the protracted reproductive interval of S. mituskurii, sexual conflict that results from conflicting male and female reproductive strategies may favor the development of female mating avoidance behavior to minimize trauma. In S. mitsukurii this behavior includes segregation of sexes and an asynchronous reproductive cycle.

Cases concerning polygamous households can present difficult challenges for family courts. Though a growing number of Americans practice polygamy, the lifestyle still remains shrouded in mystery. Many polygamists are religious (and sometimes racial) minorities that have suffered from discrimination. The most influential judicial precedents concerning polygamy come from the nineteenth century and are tinged with religious and racial stereotypes, which can make judges uncomfortable with citing those decisions. There is a need for reliable, unprejudiced, and up-to-date information about polygamy that judges can cite while maintaining an image of objectivity and impartiality. This Article seeks to provide that resource. It provides information about the evolutionary influences that shape polygamy, how polygamy is practiced in the modern world, and common problems affecting polygamous households that judges should be aware of.

Little is known about the reproductive behaviors and the actual outcomes of mating attempts in the gopher tortoise (Gopherus polyphemus). We examined the mating system and reproductive behaviors of a population of gopher tortoises in central Florida. Using microsatellite ...

Effective management of exploited species demands contemporary knowledge of population structure and mating patterns. Genetic markers can prove useful in providing this knowledge. Despite its commercial importance, genetic markers for American lobster (Homarus americanus) are limited. We developed 12 tetra- and 1 trinucleotide microsatellite loci for American lobster that exhibit little stuttering after PCR amplification. Gene diversity of these loci ranged from 0.516 to 0.929. A four-locus multiplex permits rapid genotyping of progeny in parentage experiments with a paternity exclusion probability over the four loci of 97.8%. We examined the loci for conformity to Hardy-Weinberg expectations (HWE) and linkage using individuals from one location and found that four loci deviated from HWE. We also tested inheritance and pairwise linkage using 48 embryos from each of two females. With the exception of two loci that were derived from the same clone and separated by 72 bp, no evidence o...

Reproductive success is a critical measure of an organism’s fitness. Determining reproductive success in vertebrates is confounded by the concealed mechanism and timing of fertilization (e.g., sperm competition and storage). To assess the relationship between observed mating behavior and reproductive success in the central Asian tortoise, Testudo horsfieldii Gray, 1844, we determined individual genotypes from a captive colony of adults and their offspring. We constructed a size-selected genomic library from T. horsfieldii and screened for polymorphic microsatellite markers. The screen resulted in identification of two novel microsatellite regions. Cross-species amplification of microsatellite markers using primers developed for the bog turtle, Glyptemys muhlenbergii (Schoepff, 1801), resulted in isolation of three additional polymorphic microsatellites for T. horsfieldii. The five loci, which have between 5 and 17 alleles and observed heterozygosities between 0.44 and 0.90, were use...

[Abstract] In this protocol, determination of seed paternity by microsatellite markers in Nicotiana attenuata is described. However, this does not include a protocol for the novel marker selection/identification, but rather exploits the markers generated for a closely related species N.

The number of sires fertilizing a given dam is a key parameter of the mating system in species with spatially restricted offspring dispersal, since genetic relatedness among maternal sibs determines the intensity of sib competition. In flowering plants, the extent of multiple paternity is determined by factors such as floral biology, properties of the pollen vector, selfing rate, spatial organization of the population, and genetic compatibility between neighbours. To assess the extent of multiple paternity and identify ecological factors involved, we performed a detailed study of mating patterns in a small population of a self-incompatible clonal herb, Arabidopsis halleri. We mapped and genotyped 364 individuals and 256 of their offspring at 12 microsatellite loci and jointly analysed the level of multiple paternity, pollen and seed dispersal, and spatial genetic structure. We found very low levels of correlated paternity among sibs (P(full-sib) = 3.8%) indicating high multiple pate...