The application of Y-chromosome analysis is expanding in fields such as forensic science and genealogy. By researching the potential polymorphisms this chromosome can present, we can further our ability to assess DNA profiles for these disciplines to avoid erroneous exclusions of paternal linkage, wrongful convictions based on forensic evidence, and other misinformed genetic conclusions. The conservation of Y-haplotypes during transmission occurs due to a relative lack of genetic recombination events in the inheritance of the Y-chromosome [1]. However, random mutation events can occur in a paternal line resulting in haplotype changes. These changes can include allele duplications and deletions that occur at the STR and SNP loci used in forensic DNA analysis. This can become important in cases of sexual assault where male-female mixture samples have low amounts of male DNA such that the male signal is not amplified in currently used STR multiplexes [7]. In this study, we analyzed a father and his eleven sons using two different methodologies for genetic analysis; next generation sequencing and capillary electrophoresis. The samples were obtained from the Coriell Institute for Medical Research located in Hamden, NJ, in the form of frozen DNA extracts isolated from a blood-sourced lymphocyte cell culture [22]. DNA from these samples was tested with the ForenSeqTM DNA Signature Prep Kit [14] (Verogen, San Diego, CA) primer set A and the YFilerTM Plus PCR Amplification Kit [24] (Thermo Fisher Scientific, Waltham, MA). Using these two platforms, three Y-STR loci were identified as discordant between the father and all of his eleven sons. In all three instances, the father possessed the same allele as the sons as well as one additional allele. At two of these loci (DYS449 and DYS635), the additional allele was one repeat (4bp) longer than that of the shared allele. At the other locus (DYS458), the additional allele was three repeats (12bp) longer than that of the shared allele. Following read count and peak height analysis, it was concluded that these double allele loci are not the product of stutter and are potentially the product of a non-inheritable mutation. With the knowledge that the DNA was extracted from a blood lymphocyte cell culture, it is believed that a somatic mutation may be present in the cell line. We are not able to determine whether the mutations exist in the blood of the father (true somatic mutations) or occurred as a result of the cell culture process. Throughout the study, details concerning the position of these loci on the Y-chromosome, the repeat motifs of the alleles, and the potential for duplication and/or stutter as the originating event are discussed in an effort to further understand this phenomenon. Potential locus duplications were compared to those reported on the National Institute of Standards and Technology STRBase [21] list of allele variations and also to information found in literature. The observed DYS635 locus had an allele designation of 21,22 which is reported on STRBase. The DYS449 and DYS458 loci showed potential allele-specific locus duplications that were not found on STRBase. The implications of potentially undocumented non-inheritable allele patterns in the Y-chromosome, such as this, are significant when considering comparisons between DNA obtained from germline cells (sperm) versus a known casework sample which is usually obtained from blood or saliva [7].

The African wild dog, second most endangered carnivore in Africa, has a well-developed, highly cooperative pack system. The usual structure of a pack consists of a dominant breeding pair, the alpha male and female, several subordinates, non-breeding adults and dependent offspring. Domestic dog microsatellites were used to study the parentage in three packs and confirm that more than one dog, including the subordinate males, can sire pups within a litter as previously suggested. The study was performed on two isolated populations of wild dogs in the North West Province of South Africa. In Madikwe Game Reserve, skin samples from 47 dogs were obtained by means of biopsy darts (adults) and skin slivers taken from the ear (subadults) and stored in absolute ethanol. In Pilanesberg National Park, blood samples from 18 captured dogs were collected in EDTA blood tubes. The wild dogs were photographed and individually identified according to coat patterns. Behavioural data to determine ranking were collected from all three packs. DNA was extracted from collected samples using proteinase-K digestion followed by isolation of DNA with phenol/chloroform/isoamyl alcohol. A total of 16 microsatellite loci that consistently amplified and appeared to be polymorphic in wild dogs, were used. Polymerase Chain Reaction (PCR) was performed using two panels of microsatellite loci in multiplex reactions. An amount of 1 µl of PCR product was loaded on to the 3130 XL Genetic Analyser with Genescan 500 LIZ (Applied Biosystems) size standard and analysed using STRand (Board of Regents, University of California) software program. CERVUS 2.0 software was used to calculate allele frequencies, expected and observed heterozygosity, frequency of null alleles, polymorphic information content and exclusion probabilities for parentage assignment. Parentage verification was also performed manually. The parentage analysis revealed that at least one pup was not sired by the alpha male in each of the five litters studied. Although previous studies suggested that the alpha male sires the majority of offspring in the pack, our results confirm that subordinate males commonly sire pups with the alpha female if and when the opportunity arises. This is possibly a mechanism to decrease the effects of inbreeding. / Dissertation (MSc (Veterinary Sciences))--University of Pretoria, 2006. / Production Animal Studies / unrestricted

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第21334号 / 理博第4430号 / 新制||理||1636(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 古市 剛史, 教授 湯本 貴和, 教授 髙井 正成 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

Due to an extreme asymmetry in parental investment, raising the potential for sexual conflict, orangutans provide unique insights into the role of sexual conflict in male and female reproductive strategies. Sexual selection acts on reproductive strategies, selecting for strategies that increase an individual's reproductive success. Sexual conflict results when the reproductive strategies of one sex impose costs on the other. Three forms of sexual selection have been documented in orangutans—male-male competition, female choice, and sexual coercion. This dissertation asks (1) how males employ reproductive strategies to increase their likelihood of reproductive success in the face of multi-male mating by females and (2) how females employ reproductive strategies to enact female choice and increase infant survival in the face of male-male competition and sexual coercion. I investigate these two questions using genetic paternity, long-term association data, and a year of behavioral data from orangutans (Pongo pygmaeus wurmbii) in Gunung Palung National Park, West Kalimantan, Indonesia. Brown-modified Hinde Indices, initiation and termination of associations, and following data reveal that female participation is necessary to sustain longer male-female associations and females use facultative associations to employ mate choice. Genetic paternity determination found low reproductive skew, with flanged males siring more offspring than unflanged males. Investigation of female infanticide avoidance strategies showed that females with dependent offspring under age six associate with males less often than other categories of females do, and mothers decrease the distance with their offspring during associations with males. These results highlight the importance of both female choice and male-male competition in reproductive outcomes, and illustrate how facultative associations play a key role in the reproductive strategies of both male and female orangutans. Both sexes’ strategies are studied, demonstrating the dynamic co-evolution of strategies and counterstrategies. I also consider the implications of these findings for the evolution of male bimaturism. Examining orangutan mating and reproductive behaviors deepens our understanding of how sexual conflict and sexual selection have shaped their unusual mating system and broadens our understanding of sexual conflict in reproductive strategies in a species with an extreme disparity between maternal and paternal investment. / 2025-08-31T00:00:00Z

Our paper analyzes how paid parental leave schemes affect female labor force participation in Sweden. We examine this question on municipality level from 2003 to 2019. The purpose of this paper is to examine the role of a policy reform made in 2016 and analyze how it mainly affects women and their participation rate. It contributes to the fields of economics but also has a sociological aspect. We expect the policy reform to increase the share of parental leave days taken out by men, decrease the women's share, and increase female labor force participation. The empirical results do not show statistically significant evidence that the reform in 2016 increased or decreased women's participation rate. However, the share of net days taken out by men rises, and the share of female net days falls.

The purpose of the present study was to investigate the factors that may be related to employees' decisions to use the family-friendly benefits (e.g., maternity/paternity leave, flexible work schedule) that are offered to them by their employers. Research has shown that both employees and organizations benefit when employees use family-friendly benefits. However, research has also shown that many employees do not take advantage of such benefits. Studies examining this issue are limited, and much of the research that has been conducted is anecdotal and atheoretical. The present study overcame this problem by empirically examining the use of family-friendly benefits within the theoretical context of Ajzen's (1991) theory of planned behavior. The results of this study support the theory of planned behavior. Specifically, the results indicated that whether an individual perceived he/she had control over the use of family-friendly benefits was the most predictive of whether he/she intended to use them. Whether the individual perceived that others would approve of these behaviors was also predictive of intention to perform the behaviors. In addition, an individual's intention to take leave or use a flexible work schedule was the most predictive of whether he or she actually engaged in the behaviors. Implications for practice as well as future research directions are also discussed.

Considering the high reproductive investment of the social male and the cost to the female of losing this benefit by soliciting copulations outside the social pair bond, it is expected that most raptor populations would exhibit low to no occurrence of extra-pair paternity (EPP). This holds true for the majority of raptor species studied to date with only one exception of an urban Cooper's hawk (Accipiter cooperii) study which reported an unexpectedly high extra-pair young frequency of 19.29%. In our study we examined the frequency of EPP within a red-shouldered hawk (Buteo lineatus) population residing in the suburban/urban matrix of southwest Ohio. During the breeding seasons of 2018 and 2019, 181 breeding age and nestling individuals were color-banded and sampled for genetic analysis using nine microsatellite loci. After genotyping a total of 40 broods (with at least two nestlings per brood) and both presumptive parents of each brood, no clear evidence of EPP was detected. However, at one nest site, the entire brood of four chicks was not sired by the adult male observed during the courtship period, nor another adult male observed tending the chicks later in the season. We suspect that this particular nest represented two instances of rapid mate replacement rather than extra-pair fertilization by a third unsampled male, because none of the chicks were sired by either of the two adult males observed at the nest. We also reviewed potential factors contributing to our finding of overall genetic monogamy in our study population in comparison to other raptor taxa EPP studies. Our results suggested that factors other than habitat composition alone play an important role in determining the type of breeding strategy exhibited by different raptor populations.

No description available.

京都大学 / 新制・課程博士 / 博士(理学) / 甲第24076号 / 理博第4843号 / 新制||理||1693(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 中川 尚史, 准教授 中村 美知夫, 教授 中務 真人 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

External fertilization makes male anurans susceptible to direct intrasexual competition for fertilization opportunities at the egg mass. The red-eyed treefrog, Agalychnis callidryas, is one species in which pairs of males appear to simultaneously fertilize the clutch of a Single female. DNA fingerprinting revealed the presence of multiple paternity in two egg clutches examined from two matings involving a female with two males. The breeding biology of females and the potential costs and benefits of mating with multiple males were examined. Females were found to decrease the number of eggs in matings with multiple males. In addition, amplexed females moving toward Oviposition sites avoided secondary males by moving when approached by secondary males. Mortality to the eggs as a result of multiple males attempting to amplex females is suggested as the reason females avoid multiple males. Males were found to exhibit calling site defense from other males. Males used a combination of auditory and a visual behavior in defending calling sites. The call types are described and the contexts within which calls occur is discussed. Density of frogs was found to be a better indicator of the occurrence of matings involving multiple males than the operational sex ratio (number of males/number of females). / Ph. D.