Search results for "Sexual behavior"

Low levels of relatedness on black grouse leks despite male philopatry

2008

In lekking species, males cluster on specific areas for display (the leks) and females generally prefer to copulate with males on large aggregations. The maintenance of leks in which only a few males reproduce might be explained if subordinate males gain indirect fitness benefits. By joining a lek on which relatives are displaying, subordinates might attract more females to the lek thereby increasing the mating opportunities of their kin. In black grouse, a genetic structure among leks has previously been found suggesting that relatives could display together. Using 11 microsatellite loci, we extended this result by testing for the presence of kin structures in nine black grouse leks (101 m…

Using genetic markers to unravel the origin of birds converging towards pre-migratory sites

2018

AbstractIdentifying patterns of individual movements in spatial and temporal scales can provide valuable insight into the structure of populations and the dynamics of communities and ecosystems. Especially for migrating birds, that can face a variety of unfavorable conditions along their journey, resolving movements of individuals across their annual cycle is necessary in order to design better targeted conservation strategies. Here, we studied the movements of a small migratory falcon, the Lesser Kestrel (Falco naumanni), by genetically assigning feathers from individuals of unknown origin that concentrate in large roosts during the pre-migratory period. Our findings suggest that birds fro…

Distortion of symmetrical introgression in a hybrid zone: evidence for locus-specific selection and uni-directional range expansion

2006

The fate of species integrity upon natural hybridization depends on the interaction between selection and dispersal. The relative significance of these processes may be studied in the initial phase of contact before selection and gene flow reach equilibrium. Here we study a hybrid zone of two salamander species, Lyciasalamandra antalyana and Lyciasalamandra billae, at the initial phase of hybridization. We quantify the degree and mode of introgression using nuclear and mtDNA markers. The hybrid zone can be characterized as an abrupt transition zone, the central hybrid zone being only c. 400 m, but introgressed genes were traced up to 3 km. Introgression was traced in both sexes but gene flo…

No inbreeding depression but increased sexual investment in highly inbred ant colonies.

2012

Inbreeding can lead to the expression of deleterious recessive alleles and to a subsequent fitness reduction. In Hymenoptera, deleterious alleles are purged in haploid males moderating inbreeding costs. However, in these haplodiploid species, inbreeding can result in the production of sterile diploid males. We investigated the effects of inbreeding on the individual and colony level in field colonies of the highly inbred ant Hypoponera opacior. In this species, outbreeding winged sexuals and nest-mating wingless sexuals mate during two separate reproductive periods. We show that regular sib-matings lead to high levels of homozygosity and the occasional production of diploid males, which spo…

Inbreeding depression in an insect with maternal care: influences of family interactions, life stage and offspring sex.

2013

Although inbreeding is commonly known to depress individual fitness, the severity of inbreeding depression varies considerably across species. Among the factors contributing to this variation, family interactions, life stage and sex of offspring have been proposed, but their joint influence on inbreeding depression remains poorly understood. Here, we demonstrate that these three factors jointly shape inbreeding depression in the European earwig, Forficula auricularia. Using a series of cross-breeding, split-clutch and brood size manipulation experiments conducted over two generations, we first showed that sib mating (leading to inbred offspring) did not influence the reproductive success of…

Trends in HIV sexual prevention: Attitudinal beliefs and behavioral intention in Spanish young people over the past two decades (1999-2020).

2022

Abstract Despite preventive efforts, HIV exposure is still a concern for public health. The current prevalence is related to unsafe sex, which is based on socio-cognitive variables. Therefore, information about these variables is required to verify whether the past preventive strategies have been effective and improve the future ones. However, there is not updated information to adjust future preventive interventions. For this reason, this study analyzes trends by gender in Spanish young people over the past two decades in perceived susceptibility to HIV, severity perceived to HIV, condom confidence and the intention of condom use, from 1999 to 2020. For this purpose, 11,665 Spanish young p…

Network analysis of knowledge and practices regarding sexual and reproductive health: a study among adolescent street girls in Kinshasa (DRC)

2016

The aim of the study was to ascertain the influence of knowledge and interventions in sexual and reproductive health and contraception practices among adolescent street girls from Kinshasa, Democratic Republic of the Congo.A cross-sectional study was carried out among street girls between 12 and 21 years of age. A standardised questionnaire was used, encompassing socio-demographic data and knowledge and practices regarding sexual and reproductive health. A network analysis was carried out.The study comprised 293 street girls. The mean age was 17.1 years (range 12-21 years) and the mean time spent living on the streets was 3.9 years (range 0-15 years). Commercial sex was reported by 78.5% (9…

2014

Published version of an article from the journal: Health and Quality of Life Outcomes. Also available from the publisher: http://dx.doi.org/10.1186/1477-7525-12-43

Disparities in Accessing Sexual and Reproductive Health Services at the Intersection of Disability and Female Adolescence in Tanzania

2021

Despite at times having greater needs for sexual and reproductive health (SRH) services, adolescents with disabilities often face challenges when trying to access them. This inaccessibility is further exacerbated during female adolescence. The qualitative study examines how SRH services respond to the characteristics of Tanzanian adolescent females with disabilities. We used the method of empathy-based stories to investigate the perceptions of 136 adolescent females with disabilities of their access to SRH services in Tanzania. The study used thematic content analysis and the Levesque model of health care access was applied as an analytical framework. The results demonstrate that discrimina…

Short- and long-term population dynamical consequences of asymmetric climate change in black grouse

2006

Temporal asymmetry in patterns of regional climate change may jeopardize the match between the proximate and ultimate cues of the timing of breeding. The consequences on short- and long-term population dynamics and trends as well as the underlying mechanisms are, however, often unknown. Using long-term data from Finland, we demonstrate that black grouse ( Tetrao tetrix ) have responded to spring warming by advancing both egg-laying and hatching. However, early summer (the time of hatching) has not advanced, and chicks have to face colder post-hatching conditions. Demonstrating that these conditions are critical to post-hatching survival, we show that chicks are increasingly suffering highe…