Levels Of Genetic Relatedness Research Articles

Molecular characterization of some currants (Ribes species) from Türkiye using inter-primer binding site (iPBS) and simple sequence repeat (SSR) markers

AbstractThis study was carried out to determine the genetic relationships and variation levels among currant genotypes and cultivars in Türkiye. Ten currant cultivars and one hybrid Jostaberry cultivar, which are breeding products of Europe but are best known and have high commercial value in Türkiye, were used. One black-fruited currant cultivar from Türkiye was included. In addition, 14 currant genotypes naturally grown in Türkiye were used. In this study, 14 retrotransposon-based inter-primer binding site (iPBS) and 10 microsatellite-based simple sequence repeat (SSR) markers were used for a total of 26 currant samples. By evaluating the allele profiles obtained from PCR and capillary electrophoresis with iPBS and SSR primers, the size range, average number of alleles, total number of alleles, number of polymorphic alleles, polymorphism rate, heterozygosity, polymorphism information content, marker index and discriminating power were determined successfully. In addition, unweighted pair group method with arithmetic mean (UPGMA) dendrograms and principal coordinate analysis (PCoA) were constructed and performed. The amounts of amplification product produced using iPBS and SSR markers for currant species with different fruit colours were also compared. In this study, it was proven that the level of genetic relatedness among currant cultivars and genotypes can be determined with high accuracy by iPBS markers. Moreover, the use of iPBS markers in currants was performed for the first time in this study. On the other hand, with the preferred SSR markers, the level of genetic relatedness among currants was successfully determined.

Dynamic shifts in social network structure and composition within a breeding hybrid population.

Mating behaviour and the timing of reproduction can inhibit genetic exchange between closely related species; however, these reproductive barriers are challenging to measure within natural populations. Social network analysis provides promising tools for studying the social context of hybridization, and the exchange of genetic variation, more generally. We test how social networks within a hybrid population of California Callipepla californica and Gambel's quail Callipepla gambelii change over discrete periods of a breeding season. We assess patterns of phenotypic and genotypic assortment, and ask whether altered associations between individuals (association rewiring), or changes to the composition of the population (individual turnover) drive network dynamics. We use genetic data to test whether social associations and relatedness between individuals correlate with patterns of parentage within the hybrid population. To achieve these aims, we combine RFID association data, phenotypic data and genomic measures with social network analyses. We adopt methods from the ecological network literature to quantify shifts in network structure and to partition changes into those due to individual turnover and association rewiring. We integrate genomic data into networks as node-level attributes (ancestry) and edges (relatedness, parentage) to test links between social and parentage networks. We show that rewiring of associations between individuals that persist across network periods, rather than individual turnover, drives the majority of the changes in network structure throughout the breeding season, and that the traits involved in phenotypic/genotypic assortment were highly dynamic over time. Social networks were randomly assorted based on genetic ancestry, suggesting weak behavioural reproductive isolation within this hybrid population. Finally, we show that the strength of associations within the social network, but not levels of genetic relatedness, predicts patterns of parentage. Social networks play an important role in population processes such as the transmission of disease and information, yet there has been less focus on how networks influence the exchange of genetic variation. By integrating analyses of social structure, phenotypic assortment and reproductive outcomes within a hybrid zone, we demonstrate the utility of social networks for analysing links between social context and gene flow within wild populations.

Interactions among individuals of Setaria Italica at different levels of genetic relatedness under different nutrient and planting density conditions

Plants frequently interrelate with their neighbors at different levels of genetic relatedness in close contiguity due to sessile in nature and limited seed dispersal. Niche differentiation may diminish competition among the neighboring plants, and the interactions among neighbors may also be influenced according to their identity or genetic relatedness. However, it is still unclear how interactions among individuals at different levels of genetic relatedness can be affected by different nutrient and planting density conditions. To answer this question, we conducted a greenhouse experiment. The materials were three genotypes of Setaria italica, i.e., Special early no.1 (focal plant), GT 35-1 (neighbor) and Golden valley 808 (neighbor), and Triticum aestivum (neighbor). According to the affinity level, plants were grown with different combinations, such as close kin (A1A1), far kin (A1A2), non-kin (A1A3), and stranger group (A1B). Planting density in the pots set either short distance or long distance with low and high of two levels of nutrient supply. Results showed spike diameter, spike length and aboveground biomass significantly higher in the close-kin treatment, but simultaneously root competition was more intense at short planting distance, under the condition of low and high nutrient levels in close kin treatment as compared to other interactions. We concluded that interactions among individuals of Setaria italica at different nutrient conditions influenced by both neighbor's identity and planting density.

Combining Salmonella Dublin genome information and contact-tracing to substantiate a new approach for improved detection of infectious transmission routes in cattle populations

This study presents a new method for detection of between-herd livestock movements to facilitate disease tracing and more accurately describe network behaviour of relevance for spread of infectious diseases, including within-livestock business risk-carrying contacts that are not necessarily recorded anywhere. The study introduces and substantiates the concept of grouping livestock herds into business-units based on ownership and location in the tracing analysis of animal movement-based contact networks. To test the utility of this approach, whole core genome sequencing of 196 Salmonella Dublin isolates stored from previous surveillance and project activities was combined with information on cattle movements recorded in the Danish Cattle Database between 1997 and 2017. The aim was to investigate alternative explanations for S. Dublin circulation in groups of herds connected by ownership, but without complete records of livestock movements. The EpiContactTrace R-package was used to trace the contact networks between businesses and compare the network characteristics of businesses sharing strains of S. Dublin with different levels of genetic relatedness. The ownership-only definition proved to be an unreliable grouping approach for large businesses, which could have internal distances larger than 250 km and therefore do not represent useful epidemiological units. Therefore, the grouping was refined using spatial analysis. More than 90% of final business units formed were composed of one single cattle property, whereas multi-property businesses could reach up to eight properties in a given year, with up to 15 cattle herds having been part of the same business through the study period. Results showed markedly higher probabilities of introduction of infectious animals between proposed businesses from which the same clone of S. Dublin had been isolated, when compared to businesses with non-related strains, thus substantiating the business-unit as an important epidemiological feature to consider in contact network analysis and tracing of infection routes. However, this approach may overestimate real-life contacts between cattle properties and putatively overestimate the degree of risk-contacts within each business, since it is based solely on information about property ownership and location. This does not consider administrative and individual farmers behaviours that essentially keep two properties separated. Despite this, we conclude that defining epidemiological units based on businesses is a promising approach for future disease tracing tasks.

Development of on-shore behavior among polar bears (Ursus maritimus) in the southern Beaufort Sea: inherited or learned?

Polar bears (Ursus maritimus) are experiencing rapid and substantial changes to their environment due to global climate change. Polar bears of the southern Beaufort Sea (SB) have historically spent most of the year on the sea ice. However, recent reports from Alaska indicate that the proportion of the SB subpopulation observed on‐shore during late summer and early fall has increased. Our objective was to investigate whether this on‐shore behavior has developed through genetic inheritance, asocial learning, or through social learning. From 2010 to 2013, genetic data were collected from SB polar bears in the fall via hair snags and remote biopsy darting on‐shore and in the spring from captures and remote biopsy darting on the sea ice. Bears were categorized as either on‐shore or off‐shore individuals based on their presence on‐shore during the fall. Levels of genetic relatedness, first‐order relatives, mother–offspring pairs, and father–offspring pairs were determined and compared within and between the two categories: on‐shore versus off‐shore. Results suggested transmission of on‐shore behavior through either genetic inheritance or social learning as there was a higher than expected number of first‐order relatives exhibiting on‐shore behavior. Genetic relatedness and parentage data analyses were in concurrence with this finding, but further revealed mother–offspring social learning as the primary mechanism responsible for the development of on‐shore behavior. Recognizing that on‐shore behavior among polar bears was predominantly transmitted via social learning from mothers to their offspring has implications for future management and conservation as sea ice continues to decline.

Kin recognition in rice (Oryza sativa) lines.

Kin recognition is an important mediator of interactions within individuals of a species. Despite increasing evidence of kin recognition in natural plant populations, relatively little is known about kin recognition in crop species where numerous cultivars have been generated by artificial selection. We identified rice (Oryza sativa) cultivars with the ability for kin recognition from two sets of indica-inbred and indica-hybrid lines at different levels of genetic relatedness. We then assessed this ability among kin and nonkin and tested potential mechanisms in a series of controlled experiments and field trails. Rice cultivars with the ability for kin recognition were capable of detecting the presence of kin and nonkin and responded to them by altering root behavior and biomass allocation, particularly for grain yield. Furthermore, we assessed the role of root exudates and found a root-secreted nitrogen-rich allantoin component to be responsible for kin recognition in rice lines. Kin recognition in rice lines mediated by root exudates occurs in a cultivar-dependent manner. Rice cultivars with the ability for kin recognition may increase grain yield in the presence of kin. Such an improvement of grain yield by kin recognition of cultivar mixtures offers many implications and applications in rice production.

Generating Improved Experimental Designs with Spatially and Genetically Correlated Observations Using Mixed Models

The aim of this study was to generate and evaluate the efficiency of improved field experiments while simultaneously accounting for spatial correlations and different levels of genetic relatedness using a mixed models framework for orthogonal and non-orthogonal designs. Optimality criteria and a search algorithm were implemented to generate randomized complete block (RCB), incomplete block (IB), augmented block (AB) and unequally replicated (UR) designs. Several conditions were evaluated including size of the experiment, levels of heritability, and optimality criteria. For RCB designs with half-sib or full-sib families, the optimization procedure yielded important improvements under the presence of mild to strong spatial correlation levels and relatively low heritability values. Also, for these designs, improvements in terms of overall design efficiency (ODE%) reached values of up to 8.7%, but these gains varied depending on the evaluated conditions. In general, for all evaluated designs, higher ODE% values were achieved from genetically unrelated individuals compared to experiments with half-sib and full-sib families. As expected, accuracy of prediction of genetic values improved as levels of heritability and spatial correlations increased. This study has demonstrated that important improvements in design efficiency and prediction accuracies can be achieved by optimizing how the levels of a treatment are assigned to the experimental units.

Genetic Diversity in Drumstick of Andaman Islands and Their Relatedness with Probable Introduction Sites from Mainland India

The study investigated genetic diversity in Moringa oleifera Lam. samples (63) from nine islands in Andaman and Nicobar Islands (India) and their relatedness with samples (5) from their probable source regions in mainland India. The polymerase chain reaction analysis with polymorphic random fragment polymorphic DNA (RAPD) (5) and inter simple sequence repeat (ISSR) (20) markers generated 987 and 4190 amplicons, respectively. The RAPD analysis resulted into two main and eight sub-clusters and ISSR markers generated two main and five sub-clusters. Extent of similarity in 68 samples was revealed to be 49% by RAPDs to 53% by ISSR markers. Average polymorphism information content (PIC) value ranged from 0.47 to 0.50 for the studied markers. Maximum collections from the islands were grouped along with samples from Tamil Nadu, Andhra Pradesh and Kerala which suggest high level of genetic relatedness. The information on influence of ‘isle factor’ in genetic divergence of introduced drumsticks is useful for continuance of studies on genetic changes for adaptation.

Genetic characterization of <i>Salmonella</i> and <i>Shigella</i> spp. isolates recovered from water and riverbed sediment of the Apies River, South Africa

Riverbed sediment is a vital component of river ecosystems and plays an important role in many geomorphological and ecological processes. However, when re-suspension occurs, pathogenic bacteria associated with sediment particles may be released into the water column, thus creating a health risk to those who use such water for drinking, household and recreational purposes. The aim of this study was to investigate the presence of bacterial pathogens Salmonella spp. and Shigella spp. in the Apies River and to ascertain whether there was any level of genetic relatedness between river water and riverbed sediment isolates of these pathogenic bacteria. A total of 124 water and sediment samples were collected from a site located on the Apies Rivers upstream of the Daspoort Wastewater Treatment Works, Pretoria, Gauteng, South Africa, between August and November 2014. In order to detect and identify the target bacteria, samples were analysed by culture-dependent and culture-independent techniques (quantitative real-time PCR). Genetic relatedness was established using Sanger sequencing of the invA gene of Salmonella spp. and ipaH of Shigella spp. Results of this study displayed the presence of the target bacteria both in the water and sediment of the river. The phylogenetic tree of Salmonella spp. revealed a ≥ 99% and 99% genetic relatedness between river water and riverbed sediment isolates for Salmonella spp. and Shigella spp., respectively. The degree of genetic relatedness between sediment and water pathogen isolates suggests that these organisms could possibly have a common origin and that there could be possible movement of microorganisms between the water column and the sediments. Keywords: Salmonella spp., Shigella spp., river water, riverbed sediment, genetic relatedness

Joint Estimation of Relatedness Coefficients and Allele Frequencies from Ancient Samples.

Here, we develop and test a method to address whether DNA samples sequenced from a group of fossil hominin bone or tooth fragments originate from the same individual or from closely related individuals. Our method assumes low amounts of retrievable DNA, significant levels of sequencing error, and contamination from one or more present-day humans. We develop and implement a maximum likelihood method that estimates levels of contamination, sequencing error rates, and pairwise relatedness coefficients in a set of individuals. We assume that there is no reference panel for the ancient population to provide allele and haplotype frequencies. Our approach makes use of single nucleotide polymorphisms (SNPs) and does not make assumptions about the underlying demographic model. By artificially mating genomes from the 1000 Genomes Project, we determine the numbers of individuals at a given genomic coverage that are required to detect different levels of genetic relatedness with confidence.

Identity recognition in response to different levels of genetic relatedness in commercial soya bean.

Identity recognition systems allow plants to tailor competitive phenotypes in response to the genetic relatedness of neighbours. There is limited evidence for the existence of recognition systems in crop species and whether they operate at a level that would allow for identification of different degrees of relatedness. Here, we test the responses of commercial soya bean cultivars to neighbours of varying genetic relatedness consisting of other commercial cultivars (intraspecific), its wild progenitor Glycine soja, and another leguminous species Phaseolus vulgaris (interspecific). We found, for the first time to our knowledge, that a commercial soya bean cultivar, OAC Wallace, showed identity recognition responses to neighbours at different levels of genetic relatedness. OAC Wallace showed no response when grown with other commercial soya bean cultivars (intra-specific neighbours), showed increased allocation to leaves compared with stems with wild soya beans (highly related wild progenitor species), and increased allocation to leaves compared with stems and roots with white beans (interspecific neighbours). Wild soya bean also responded to identity recognition but these responses involved changes in biomass allocation towards stems instead of leaves suggesting that identity recognition responses are species-specific and consistent with the ecology of the species. In conclusion, elucidating identity recognition in crops may provide further knowledge into mechanisms of crop competition and the relationship between crop density and yield.

Negotiation and appeasement can be more effective drivers of sociality than kin selection.

Two alternative frameworks explain the evolution of cooperation in the face of conflicting interests. Conflicts can be alleviated by kinship, the alignment of interests by virtue of shared genes, or by negotiation strategies, allowing mutually beneficial trading of services or commodities. Although negotiation often occurs in kin-structured populations, the interplay of kin- and negotiation-based mechanisms in the evolution of cooperation remains an unresolved issue. Inspired by the biology of a cooperatively breeding fish, we developed an individual-based simulation model to study the evolution of negotiation-based cooperation in relation to different levels of genetic relatedness. We show that the evolution of negotiation strategies leads to an equilibrium where subordinates appease dominants by conditional cooperation, resulting in high levels of help and low levels of aggression. This negotiation-based equilibrium can be reached both in the absence of relatedness and in a kin-structured population. However, when relatedness is high, evolution often ends up in an alternative equilibrium where subordinates help their kin unconditionally. The level of help at this kin-selected equilibrium is considerably lower than at the negotiation-based equilibrium, and it corresponds to a level reached when responsiveness is prevented from evolving in the simulations. A mathematical invasion analysis reveals that, quite generally, the alignment of payoffs due to the relatedness of interaction partners tends to impede selection for harsh but effective punishment of defectors. Hence kin structure will often hamper rather than facilitate the evolution of productive cooperation.

Transcriptome sequencing of three Pseudo-nitzschia species reveals comparable gene sets and the presence of Nitric Oxide Synthase genes in diatoms

Diatoms are among the most diverse eukaryotic microorganisms on Earth, they are responsible for a large fraction of primary production in the oceans and can be found in different habitats. Pseudo-nitzschia are marine planktonic diatoms responsible for blooms in coastal and oceanic waters. We analyzed the transcriptome of three species, Pseudo-nitzschia arenysensis, Pseudo-nitzschia delicatissima and Pseudo-nitzschia multistriata, with different levels of genetic relatedness. These species have a worldwide distribution and the last one produces the neurotoxin domoic acid. We were able to annotate about 80% of the sequences in each transcriptome and the analysis of the relative functional annotations allowed comparison of the main metabolic pathways, pathways involved in the biosynthesis of isoprenoids (MAV and MEP pathways), and pathways putatively involved in domoic acid synthesis. The search for homologous transcripts among the target species and other congeneric species resulted in the discovery of a sequence annotated as Nitric Oxide Synthase (NOS), found uniquely in Pseudo-nitzschia multistriata. The predicted protein product contained all the domains of the canonical metazoan sequence. Putative NOS sequences were found in other available diatom datasets, supporting a role for nitric oxide as signaling molecule in this group of microalgae.

Dispersal distance is influenced by parental and grand-parental density.

Non-genetic transmission of information across generations, so-called parental effects, can have significant impacts on offspring morphology, physiology, behaviour and life-history traits. In previous experimental work using the two-spotted spider mite Tetranychus urticae Koch, we demonstrated that dispersal distances increase with local density and levels of genetic relatedness. We here show that manipulation of parental and grand-parental density has a significant effect on offspring dispersal distance, of the same order of magnitude as manipulation of offspring density. We demonstrate that offspring exposed to the same density disperse further if they were born to parents exposed to higher density compared with parents exposed to low density. Offspring dispersal distance also increases when grand-parents were exposed to higher density, except for offspring exposed to low densities, which disperse at shorter distances whatever the grand-parental density. We also show that offspring from mothers exposed to higher densities were overall larger, which suggests that parents in high densities invest more in individual offspring, enabling them to disperse further. We propose that our findings should be included in models investigating the spread rate of invasive species or when predicting the success of conservation measures of species attempting to track changing climates.

Genetic diversity and gene flow of some Persian walnut populations in southeast of Iran revealed by SSR markers

Iran is reported to be a center of diversity for Juglans regia and wild walnut trees are found in virtually every corner of the country. Thus Iran is considered a rich natural pool of walnut germplasm for developing improved genotypes. Kerman province is the most important Iranian province for walnut culture and has the largest walnut plantations in Iran. Genetic structure and gene flow were analyzed in six walnut populations of this province using 17 microsatellite loci. The number of alleles per locus ranged from 4 to 11, with a total of 147 alleles and 5.16 effective alleles per locus. The polymorphism information content for the loci ranged from 0.56 to 0.82. The expected heterozygosity (H e) for the populations ranged from 0.65 to 0.87. There were differences between populations regarding the number of effective alleles and Shannon’s information index (I). In all populations, observed heterozygosity (H o) was lower than expected, but diversity within the populations was high (I = 1.5) and many of the private alleles were present at relatively high frequency. The average F st value was 0.08. The level of gene flow based on F st was high (N m = 3.01), which meant that the high level of genetic diversity maintained within each population was less susceptible to genetic drift. The geographical proximity of the populations was not correlated with their level of genetic relatedness. These results imply the high potential of walnut populations of Kerman province for breeding programs.

Using Random Amplified Polymorphic DNA (RAPD) analysis to investigation of genetic diversity, and relationships among a set of clinical Aspergillus fumigatus isolates

This study is an attempt to determine the genetic diversity and relationships among fourteen local isolate isolated from patients with Aspergillosis (Aspergillus fumigatus) by using the Random Amplified Polymorphic DNA (RAPD) technique. Twelve universal primers used in this study produced 94 bands across fourteen isolates. Of these bands, 67 bands or 71.2% were polymorphic. The size of the amplified bands ranged between 100-2000 bp. The genetic polymorphism value of each primer was determined and ranged between 33-100%. In terms of unique banding patterns, determine the finger print for six isolates the most characteristic banding pattern was for the (AFU1, AFU2, AFU3, AFU4, AFU8 and AFU14) with primer (OP F-16 , OP I-06, OP F-16, OP X-01, OP X-01and OP A-06). Genetic distances ranged from 0.12419 to 0.64404 among A. fumigatus isolates. Cluster analyses were performed to construct a dendrogram among studied A. fumigatus isolates. The cluster analysis places most of the A.fumigatus isolates isolated from patient come from yhe same area into a close relation (subcluster) showing a high level of genetic relatedness and were distinct from isolates from another area (the other subcluster). Interestingly, a number of isolates originating from the same sources did form well defined groups, indicating association between the RAPD patterns and the geographic origin of the isolates. The information generated from this study can be used in the future for controlling of Aspergillosis programs.

Biases in quantitative genetic analyses using open-pollinated progeny tests from natural tree populations

In plant quantitative genetic studies conducted ex situ, the large number of seeds produced per individual has promoted the use of open-pollinated progeny tests. In subsequent analyses, seeds collected on the same mother-plant are assumed to be half-sibs. The consequences of the departure from half-sib assumption in progeny tests have been investigated since the 1960s using simulation approaches and, more recently, using molecular-based experimental approaches. This review aims to synthesize the results and conclusions of these simulation and empirical studies. We focus on tree species, where controlled crosses are difficult to carry out experimentally and departures from half-sib assumptions occur frequently in natural populations. First, the average level of relatedness expected within maternal progeny for many tree populations is higher than that of half-sibs. This is the consequence of non-random mating resulting from the small number of effective pollen donors per female, unequal male reproductive success and/or selfing. As result, estimates of genetic variance and heritability for quantitative traits may be upward biased. Alternatively, inbreeding depression, dominance effects and the heterogeneity of the male gamete pool among females are often neglected, which may lead to underestimation of the heritability of traits. A correction based on the mean genetic relatedness between offspring and the relatedness between parents is often used to compensate those biases. However, such correction cannot accurately adjust the estimates in situations where variable levels of genetic relatedness among families, dominance effects or inbreeding depression exist within the progeny. An alternative and promising approach is the use of the “animal model” approach, which optimizes the use of molecular data and paternal information to estimate heritability more accurately.

Genetic rescue versus outbreeding depression in Vallisneria americana: Implications for mixing seed sources for restoration

The selection of seed stock for restoration remains a complex issue. Using local stock reduces the chances of outbreeding depression or genetic dilution, whereas mixing sources may increase diversity and counteract inbreeding depression. Evaluation of these opposing approaches remains difficult when planning a restoration project but is needed to increase chances of long-term population persistence. We evaluated seed production and germination success of seeds from controlled reproductive crosses of the submersed aquatic plant Vallisneria americana (wild celery) collected from populations throughout the Chesapeake Bay. We assessed differences in seeds, capsules, and germination success in three types of crosses: (1) individuals within-populations, (2) among-populations but within-genetically differentiated regions, and (3) among-regions. We observed population level differences in within-population and among-region crosses. Levels of genetic relatedness among individuals, genetic diversity within populations, or differentiation across populations did not predict reproductive success. Our data show that mixing sources from different populations and regions has both benefits and drawbacks. Thus, minimizing the risks of outbreeding and inbreeding depression, presented as a mostly dichotomous issue in the restoration literature, is not an either-or issue in V. americana.

Going that extra mile: individuals travel further to maintain face-to-face contact with highly related kin than with less related kin.

The theory of inclusive fitness has transformed our understanding of cooperation and altruism. However, the proximate psychological underpinnings of altruism are less well understood, and it has been argued that emotional closeness mediates the relationship between genetic relatedness and altruism. In this study, we use a real-life costly behaviour (travel time) to dissociate the effects of genetic relatedness from emotional closeness. Participants travelled further to see more closely related kin, as compared to more distantly related kin. For distantly related kin, the level of emotional closeness mediated this relationship - when emotional closeness was controlled for, there was no effect of genetic relatedness on travel time. However, participants were willing to travel further to visit parents, children and siblings as compared to more distantly related kin, even when emotional closeness was controlled for. This suggests that the mediating effect of emotional closeness on altruism varies with levels of genetic relatedness.

Kinship, parentage, and temporal stability in nursery colonies of Leisler’s bat (Nyctalus leisleri)

Levels of genetic relatedness within bat colonies are often unknown, and consequently the reasons for group formation and social organization are unclear. The Leisler’s bat (Nyctalus leisleri), like most temperate bat species, forms nursery colonies in summer. We used microsatellite markers to examine identity and to attempt to estimate relatedness among females within a nursery colony, over 2 consecutive years, to ascertain whether females show kinship and natal philopatry, testing the hypothesis that this is the basis of colony formation. Parentage and relatedness of young born within a colony was assessed to investigate mating patterns via male reproductive skew and whether males achieve mating success within their natal colony. While there was evidence for female philopatry, levels of genetic relatedness within colonies were low. This suggests that kinship is not a major determinant in group formation, as roosts also comprise a large number of distant relatives or non-kin. Roost switching and gene flow are likely to be high. Both sexes reproduced in their first year, whereas males appear to be the more dispersive sex. We argue that the physical environment as well as information sharing provided by communal roosting are likely to be important factors for the formation of these large natal colonies in N. leisleri and possibly other lineages of bats.