Long-term impacts of an early childhood shock on human capital: Evidence from the 1999 economic crisis in Ecuador.

This paper provides evidence on the lasting effects of the 1999 economic crisis in Ecuador on human capital formation. We show for children born during the crisis that the negative repercussions are still observable more than 10 years after macroeconomic recovery. Taking advantage of micro-level data collected in 2012 and 2014, we assess long-term impacts on health and education. After controlling for age-in-months and survey effects as well as a linear birth year-cohort trend that varies by region, we find that after 12-16 years, the cohorts born during the recession report height-for-age Z-scores that are 0.003 standard deviations (SDs) lower for each month of exposure and have 0.002 fewer years of schooling per month exposed compared to the cohorts born outside the recession years. Children exposed to the entire crisis are 0.063 SDs smaller and have 0.042 years less of schooling. Girls have lower health outcomes than boys. Concomitantly, we show that selective childbearing or excess infant mortality are unlikely to drive our results. The persistence of the negative effects points to the existence of a poverty trap suggesting that policy interventions in response to (economic) crizes should be extended beyond macroeconomic recovery to counteract long-term, micro-level consequences.

Contrasting levels of ß-diversity and underlying phylogenetic trends indicate different paths to chemical diversity in highland and lowland willow species.

Diverse specialised metabolites contributed to the success of vascular plants in colonising most terrestrial habitats. Understanding how distinct aspects of chemical diversity arise through heterogeneous environmental pressures can help us understand the effects of abiotic and biotic stress on plant evolution and community assembly. We examined highland and lowland willow species within a phylogenetic framework to test for trends in their chemical α-diversity (richness) and ß-diversity (variation among species sympatric in elevation). We show that differences in chemistry among willows growing at different elevations occur mainly through shifts in chemical ß-diversity and due to convergence or divergence among species sharing their elevation level. We also detect contrasting phylogenetic trends in concentration and α-diversity of metabolites in highland and lowland willow species. The resulting elevational patterns contribute to the chemical diversity of willows and suggest that variable selective pressure across ecological gradients may, more generally, underpin complex changes in plant chemistry.

Insights into the Taxonomically Challenging Hexaploid Alpine Shrub Willows of Salix Sections Phylicifoliae and Nigricantes (Salicaceae).

The complex genomic composition of allopolyploid plants leads to morphologically diverse species. The traditional taxonomical treatment of the medium-sized, hexaploid shrub willows distributed in the Alps is difficult based on their variable morphological characters. In this study, RAD sequencing data, infrared-spectroscopy, and morphometric data are used to analyze the phylogenetic relationships of the hexaploid species of the sections Nigricantes and Phylicifoliae in a phylogenetic framework of 45 Eurasian Salix species. Both sections comprise local endemics as well as widespread species. Based on the molecular data, the described morphological species appeared as monophyletic lineages (except for S. phylicifolia s.str. and S. bicolor, which are intermingled). Both sections Phylicifoliae and Nigricantes are polyphyletic. Infrared-spectroscopy mostly confirmed the differentiation of hexaploid alpine species. The morphometric data confirmed the molecular results and supported the inclusion of S. bicolor into S. phylicifolia s.l., whereas the alpine endemic S. hegetschweileri is distinct and closely related to species of the section Nigricantes. The genomic structure and co-ancestry analyses of the hexaploid species revealed a geographical pattern for widespread S. myrsinifolia, separating the Scandinavian from the alpine populations. The newly described S. kaptarae is tetraploid and is grouped within S. cinerea. Our data reveal that both sections Phylicifoliae and Nigricantes need to be redefined.

Evolutionary origin and establishment of a dioecious diploid-tetraploid complex.

Polyploids recurrently emerge in angiosperms, but most polyploids are likely to go extinct before establishment due to minority cytotype exclusion, which may be specifically a constraint for dioecious plants. Here we test the hypothesis that a stable sex-determination system and spatial/ecological isolation facilitate the establishment of dioecious polyploids. We determined the ploidy levels of 351 individuals from 28 populations of the dioecious species Salix polyclona, and resequenced 190 individuals of S. polyclona and related taxa for genomic diversity analyses. The ploidy survey revealed a frequency 52% of tetraploids in S. polyclona, and genomic k-mer spectra analyses suggested an autopolyploid origin for them. Comparisons of diploid male and female genomes identified a female heterogametic sex-determining factor on chromosome 15, which probably also acts in the dioecious tetraploids. Phylogenetic analyses revealed two diploid clades and a separate clade/grade of tetraploids with a distinct geographic distribution confined to western and central China, where complex mountain systems create higher levels of environmental heterogeneity. Fossil-calibrated phylogenies showed that the polyploids emerged during 7.6-2.3 million years ago, and population demographic histories largely matched the geological and climatic history of the region. Our results suggest that inheritance of the sex-determining system from the diploid progenitor as intrinsic factor and spatial isolation as extrinsic factor may have facilitated the preservation and establishment of polyploid dioecious populations.

Evolution of a hybrid zone of two willow species (Salix L.) in the European Alps analyzed by RAD-seq and morphometrics.

Natural hybridization of plants can result in many outcomes with several evolutionary consequences, such as hybrid speciation and introgression. Natural hybrid zones can arise in mountain systems as a result of fluctuating climate during the exchange of glacial and interglacial periods, where species retract and expand their territories, resulting in secondary contacts. Willows are a large genus of woody plants with an immense capability of interspecific crossing. In this study, the sympatric area of two diploid sister species, S. foetida and S. waldsteiniana in the eastern European Alps, was investigated to study the genomic structure of populations within and outside their contact zone and to analyze congruence of morphological phenotypes with genetic data. Eleven populations of the two species were sampled across the Alps and examined using phylogenetic network and population genetic structure analyses of RAD Seq data and morphometric analyses of leaves. The results showed that a homoploid hybrid zone between the two species was established within their sympatric area. Patterns of genetic admixture in homoploid hybrids indicated introgression with asymmetric backcrossing to not only one of the parental species but also one hybrid population forming a separate lineage. The lack of F1 hybrids indicated a long-term persistence of the hybrid populations. Insignificant isolation by distance suggests that gene flow can act over large geographical scales. Morphometric characteristics of hybrids supported the molecular data and clearly separated populations of the parental species, but showed intermediacy in the hybrid zone populations with a bias toward S. waldsteiniana. The homoploid hybrid zone might have been established via secondary contact hybridization, and its establishment was fostered by the low genetic divergence of parental species and a lack of strong intrinsic crossing barriers. Incomplete ecological separation and the ability of long-distance dispersal of willows could have contributed to the spatial expansion of the hybrid zone.

Genomic evidence for contrasting patterns of host-associated genetic differentiation across shared host-plant species in leaf- and bud-galling sawflies.

Resource specialization and ecological speciation arising through host-associated genetic differentiation (HAD) are frequently invoked as an explanation for the high diversity of plant-feeding insects and other organisms with a parasitic lifestyle. While genetic studies have demonstrated numerous examples of HAD in insect herbivores, the rarity of comparative studies means that we still lack an understanding of how deterministic HAD is, and whether patterns of host shifts can be predicted over evolutionary timescales. We applied genome-wide single nucleotide polymorphism and mitochondrial DNA sequence data obtained through genome resequencing to define species limits and to compare host-plant use in population samples of leaf- and bud-galling sawflies (Hymenoptera: Tenthredinidae: Nematinae) collected from seven shared willow (Salicaceae: Salix) host species. To infer the repeatability of long-term cophylogenetic patterns, we also contrasted the phylogenies of the two galler groups with each other as well as with the phylogeny of their Salix hosts estimated based on RADseq data. We found clear evidence for host specialization and HAD in both of the focal galler groups, but also that leaf gallers are more specialized to single host species compared with most bud gallers. In contrast to bud gallers, leaf gallers also exhibited statistically significant cophylogenetic signal with their Salix hosts. The observed discordant patterns of resource specialization and host shifts in two related galler groups that have radiated in parallel across a shared resource base indicate a lack of evolutionary repeatability in the focal system, and suggest that short- and long-term host use and ecological diversification in plant-feeding insects are dominated by stochasticity and/or lineage-specific effects.

Ancient DNA extraction methods for herbarium specimens: When is it worth the effort?

Premise: Herbaria harbor a tremendous number of plant specimens that are rarely used for molecular systematic studies, largely due to the difficulty in extracting sufficient amounts of high-quality DNA from the preserved plant material. Methods: We compared the standard Qiagen DNeasy Plant Mini Kit and a specific protocol for extracting ancient DNA (aDNA) (the N-phenacylthiazolium bromide and dithiothreitol [PTB-DTT] extraction method) from two different plant genera (Xanthium and Salix). The included herbarium materials covered about two centuries of plant collections. To analyze the success of DNA extraction using each method, a subset of samples was subjected to a standard library preparation as well as target-enrichment approaches. Results: The PTB-DTT method produced a higher DNA yield of better quality than the Qiagen kit; however, extracts from the Qiagen kit over a certain DNA yield and quality threshold produced comparable sequencing results. The sequencing resulted in high proportions of endogenous reads. We were able to successfully sequence 200-year-old samples. Discussion: This method comparison revealed that, for younger specimens, DNA extraction using a standard kit might be sufficient. For old and precious herbarium specimens, aDNA extraction methods are better suited to meet the requirements for next-generation sequencing.

Untying Gordian knots: unraveling reticulate polyploid plant evolution by genomic data using the large Ranunculus auricomus species complex.

Speciation via hybridization and polyploidization is a major evolutionary force in plant evolution but is still poorly understood for neopolyploid groups. Challenges are attributed to high heterozygosity, low genetic divergence, and missing information on progenitors, ploidy, and reproduction. We study the large Eurasian Ranunculus auricomus species complex and use a comprehensive workflow integrating reduced-representation sequencing (RRS) genomic data to unravel reticulate evolution, genome diversity and composition of polyploids. We rely on 97 312 restriction site-associated DNA sequencing (RAD-Seq) loci, 576 targeted nuclear genes (48 phased), and 71 plastid regions derived from 78 polyploid apomictic taxa and four diploid and one tetraploid putative sexual progenitor species. We applied (phylo)genomic structure, network, and single nucleotide polymorphism (SNP)-origin analyses. Results consistently showed only 3-5 supported and geographically structured polyploid genetic groups, each containing extant sexual and one unknown progenitor species. Combined analyses demonstrated predominantly allopolyploid origins, each involving 2-3 different diploid sexual progenitor species. Young allotetraploids were characterized by subgenome dominance and nonhybrid SNPs, suggesting substantial post-origin but little lineage-specific evolution. The biodiversity of neopolyploid complexes can result from multiple hybrid origins involving different progenitors and substantial post-origin evolution (e.g. homoeologous exchanges, hybrid segregation, gene flow). Reduced-representation sequencing genomic data including multi-approach information is efficient to delimit shallow reticulate relationships.

Highly Diverse Shrub Willows (Salix L.) Share Highly Similar Plastomes.

Plastome phylogenomics is used in a broad range of studies where single markers do not bear enough information. Phylogenetic reconstruction in the genus Salix is difficult due to the lack of informative characters and reticulate evolution. Here, we use a genome skimming approach to reconstruct 41 complete plastomes of 32 Eurasian and North American Salix species representing different lineages, different ploidy levels, and separate geographic regions. We combined our plastomes with published data from Genbank to build a comprehensive phylogeny of 61 samples (50 species) using RAxML (Randomized Axelerated Maximum Likelihood). Additionally, haplotype networks for two observed subclades were calculated, and 72 genes were tested to be under selection. The results revealed a highly conserved structure of the observed plastomes. Within the genus, we observed a variation of 1.68%, most of which separated subg. Salix from the subgeneric Chamaetia/Vetrix clade. Our data generally confirm previous plastid phylogenies, however, within Chamaetia/Vetrix phylogenetic results represented neither taxonomical classifications nor geographical regions. Non-coding DNA regions were responsible for most of the observed variation within subclades and 5.6% of the analyzed genes showed signals of diversifying selection. A comparison of nuclear restriction site associated DNA (RAD) sequencing and plastome data on a subset of 10 species showed discrepancies in topology and resolution. We assume that a combination of (i) a very low mutation rate due to efficient mechanisms preventing mutagenesis, (ii) reticulate evolution, including ancient and ongoing hybridization, and (iii) homoplasy has shaped plastome evolution in willows.

Chromosome-scale assembly of the genome of Salix dunnii reveals a male-heterogametic sex determination system on chromosome 7.

Sex determination systems in plants can involve either female or male heterogamety (ZW or XY, respectively). Here we used Illumina short reads, Oxford Nanopore Technologies (ONT) long reads and Hi-C reads to assemble the first chromosome-scale genome of a female willow tree (Salix dunnii), and to predict genes using transcriptome sequences and available databases. The final genome sequence of 328 Mb in total was assembled in 29 scaffolds, and includes 31,501 predicted genes. Analyses of short-read sequence data that included female and male plants suggested a male heterogametic sex-determining factor on chromosome 7, implying that, unlike the female heterogamety of most species in the genus Salix, male heterogamety evolved in the subgenus Salix. The S. dunnii sex-linked region occupies about 3.21 Mb of chromosome 7 in females (representing its position in the X chromosome), probably within a pericentromeric region. Our data suggest that this region is enriched for transposable element insertions, and about one-third of its 124 protein-coding genes were gained via duplications from other genome regions. We detect purifying selection on the genes that were ancestrally present in the region, though some have been lost. Transcriptome data from female and male individuals show more male- than female-biased genes in catkin and leaf tissues, and indicate enrichment for male-biased genes in the pseudo-autosomal regions. Our study provides valuable genomic resources for further studies of sex-determining regions in the family Salicaceae, and sex chromosome evolution.

"When I receive the message, it is a sign of love": symbolic connotations of SMS messages for people living with HIV in Burkina Faso.

Mobile health (mHealth) has gained considerable interest recently due to its potential to improve health outcomes in developing countries with high outreach yet low costs. Several studies have explored the use of short message service (SMS) reminders to improve antiretroviral (ARV) retention and adherence, with mixed results. The majority of these studies has a quantitative nature and employs randomized designs, which do not provide further qualitative insights about other possible impacts of the messages. Based on the qualitative assessment of an SMS intervention in Burkina Faso, which complemented a (quantitative) Randomized Controlled Trial (RCT), we show that beyond the functional role of improving ARV retention and adherence, SMS messages can also play important symbolic roles in offering psychosocial support to people living with HIV (PLHIV) and improving their perception of life. Concomitantly, we show that sufficient (ICT) literacy skills cannot be taken for granted in resource-poor settings. Yet, regardless of (ICT) literacy skills, the symbolism of care was perceived. Furthermore, we highlight the importance of complementing quantitative evidence of mHealth interventions with qualitative assessments.

Phylogenomic Relationships and Evolution of Polyploid Salix Species Revealed by RAD Sequencing Data.

Polyploidy is common in the genus Salix. However, little is known about the origin, parentage and genomic composition of polyploid species because of a lack of suitable molecular markers and analysis tools. We established a phylogenomic framework including species of all described sections of Eurasian shrub willows. We analyzed the genomic composition of seven polyploid willow species in comparison to putative diploid parental species to draw conclusions on their origin and the effects of backcrossing and post-origin evolution. We applied recently developed programs like SNAPP, HyDe, and SNiPloid to establish a bioinformatic pipeline for unravelling the complexity of polyploid genomes. RAD sequencing revealed 23,393 loci and 320,010 high quality SNPs for the analysis of relationships of 35 species of Eurasian shrub willows (Salix subg. Chamaetia/Vetrix). Polyploid willow species appear to be predominantly of allopolyploid origin. More ancient allopolyploidization events were observed for two hexaploid and one octoploid species, while our data suggested a more recent allopolyploid origin for the included tetraploids and identified putative parental taxa. SNiPloid analyses disentangled the different genomic signatures resulting from hybrid origin, backcrossing, and secondary post-origin evolution in the polyploid species. Our RAD sequencing data demonstrate that willow genomes are shaped by ancient and recent reticulate evolution, polyploidization, and post-origin divergence of species.

A Systematic Review of Mobile Phone Interventions (SMS/IVR/Calls) to Improve Adherence and Retention to Antiretroviral Treatment in Low-and Middle-Income Countries.

The use of mobile health technologies (mHealth) to ameliorate HIV care has considerably risen in low- and middle-income countries (LMICs) since 2010. Yet, the discrepancies in the results of accompanying studies warrant an updated and systematic consolidation of all available evidence. We report a systematic review of studies testing whether text/image messages, interactive voice response reminders, or calls promote adherence and retention to antiretroviral therapy (ART) in LMICs. We systematically compiled studies published in English until June 2018 from PubMed/Medline, Web of Science, WHO database, ProQuest Dissertations and Theses, and manual search. We used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2009 and used frequency analysis to assess reported findings. In total, we compiled 35 published articles: 27 completed studies and 8 protocols. Among the main 27 studies, 17 examine adherence, 5 retention, and 5 both measures. Results indicate that 56% report positive and statistically significantly impacts of mHealth on primary outcomes, the remaining 44% report insignificant results. While 41% of studies found a positive and significant effect for adherence, only 12% improved retention. The evidence shows ambiguous results (with high variability) about the effectiveness of mobile phone-assisted mHealth interventions to boost adherence and retention to ART. The literature also points to short follow-up periods, small samples, and limited geographical coverage. Hence, future research should focus on evaluating longer interventions with more patients spread across wider areas to address whether mHealth can be effectively used in LMICs.

Adaptation and biomedical transition of people living with HIV to antiretroviral treatment in Burkina Faso.

This article examines the adaptation and biomedical transition of people living with HIV (PLHIV) to antiretroviral treatment (ART) in Burkina Faso. The study employs a representative sample of 3625 randomly selected patients. Subjective and objective measures of health and their predictors are compared for short-term (≤24 months) versus longer-term ART adherents (>24 months) in a cohort study. Subjective health is measured as Likert scale self-rating and objective health as CD4 count. The results show that subjective and objective health capture different aspects of adaptation to ART: 90% of the short-term and 94% of the longer-term patients give a subjective health rating of at least good, while the objective measure of good health is higher among longer-term (42%) compared to short-term patients (27%). For subjective health, short-lived pleasures are predictors among short-term adherents while economic characteristics are determinants among longer-term patients. Meanwhile, objective health is associated with factors that determine ART adherence (i.e. participating in self-help groups). To achieve a wholistic resilience management that caters to the needs of PLHIV, we need to acknowledge adaptation to the disease and to ART and design health programs, in particular in developing countries, away from one-size-fits-all solutions to stage-of-disease specific support.

The impact of the Ethiopian health extension program and health development army on maternal mortality: A synthetic control approach.

The Ethiopian government has implemented nationwide strategies to improve access to basic health services and enhance health outcomes. The Health Extension Program (HEP) launched in 2003, expanded basic health infrastructure and local human resources. In 2011, the government introduced the Health Development Army (HDA). HDA is a women-centered community movement inspired by military structures and discipline. Its special objective is to improve maternal health outcomes. This paper uses a synthetic control approach to assess the effects of HEP and HDA on maternal mortality ratios (MMR). The MMR data are from the Global Burden of Diseases (GBD) database. A pool of 42 Sub-Saharan African countries, covering the period 1990 to 2016, is used to construct a synthetic comparator which displays a mortality trajectory similar to Ethiopia prior to the interventions. On average, since 2004, maternal mortality in the control countries exhibits a moderate downward trend. In Ethiopia, the downward trend is considerably steeper as compared to its synthetic control. By 2016, maternal mortality in Ethiopia was lower by 171 (p-value 0.048) maternal deaths per 100,000 live births as compared to its synthetic control. Between 2003 and 2016, Ethiopia's maternal mortality ratio declined from 728 to 357. These estimates suggest that a substantial proportion of this decline may be attributed to HEP/HDA. The Ethiopian experience of enhancing nation-wide access to and use of maternal health services in a short time-span is remarkable. Whether such a model may be transplanted is an open question.

RAD-seq reveals genetic structure of the F2-generation of natural willow hybrids (Salix L.) and a great potential for interspecific introgression.

BACKGROUND: Hybridization of species with porous genomes can eventually lead to introgression via repeated backcrossing. The potential for introgression between species is reflected by the extent of segregation distortion in later generation hybrids. Here we studied a population of hybrids between Salix purpurea and S. helvetica that has emerged within the last 30 years on a glacier forefield in the European Alps due to secondary contact of the parental species. We used 5758 biallelic SNPs produced by RAD sequencing with the aim to ascertain the predominance of backcrosses (F1 hybrid x parent) or F2 hybrids (F1 hybrid x F1 hybrid) among hybrid offspring. Further, the SNPs were used to study segregation distortion in the second hybrid generation. RESULTS: The analyses in STRUCTURE and NewHybrids revealed that the population consisted of parents and F1 hybrids, whereas hybrid offspring consisted mainly of backcrosses to either parental species, but also some F2 hybrids. Although there was a clear genetic differentiation between S. purpurea and S. helvetica (FST = 0.24), there was no significant segregation distortion in the backcrosses or the F2 hybrids. Plant height of the backcrosses resembled the respective parental species, whereas F2 hybrids were more similar to the subalpine S. helvetica. CONCLUSIONS: The co-occurrence of the parental species and the hybrids on the glacier forefield, the high frequency of backcrossing, and the low resistance to gene flow via backcrossing make a scenario of introgression in this young hybrid population highly likely, potentially leading to the transfer of adaptive traits. We further suggest that this willow hybrid population may serve as a model for the evolutionary processes initiated by recent global warming.

RAD sequencing resolved phylogenetic relationships in European shrub willows (Salix L. subg. Chamaetia and subg. Vetrix) and revealed multiple evolution of dwarf shrubs.

The large and diverse genus Salix L. is of particular interest for decades of biological research. However, despite the morphological plasticity, the reconstruction of phylogenetic relationships was so far hampered by the lack of informative molecular markers. Infrageneric classification based on morphology separates dwarf shrubs (subg. Chamaetia) and taller shrubs (subg. Vetrix), while previous phylogenetic studies placed species of these two subgenera just in one largely unresolved clade. Here we want to test the utility of genomic RAD sequencing markers for resolving relationships at different levels of divergence in Salix. Based on a sampling of 15 European species representing 13 sections of the two subgenera, we used five different RAD sequencing datasets generated by ipyrad to conduct phylogenetic analyses. Additionally we reconstructed the evolution of growth form and analyzed the genetic composition of the whole clade. The results showed fully resolved trees in both ML and BI analysis with high statistical support. The two subgenera Chamaetia and Vetrix were recognized as nonmonophyletic, which suggests that they should be merged. Within the Vetrix/Chamaetia clade, a division into three major subclades could be observed. All species were confirmed to be monophyletic. Based on our data, arctic-alpine dwarf shrubs evolved four times independently. The structure analysis showed five mainly uniform genetic clusters which are congruent in sister relationships observed in the phylogenies. Our study confirmed RAD sequencing as a useful genomic tool for the reconstruction of relationships on different taxonomic levels in the genus Salix.

Does health insurance coverage or improved quality protect better against out-of-pocket payments? Experimental evidence from the Philippines.

This paper explores whether health insurance coverage or improved quality at the hospital level protect better against out-of-pocket payments. Using data from a randomized policy experiment in the Philippines, we found that interventions to expand insurance coverage and improve provider quality both had an impact on out-of-pocket payments. The sample consists of 3121 child-patient patient observations across 30 hospitals either at baseline in 2003/04 or at the follow-up in 2007/08. Compared to controls, interventions that expanded insurance and provided performance-based provider payments to improve quality both resulted in a decline in out-of-pocket spending (21% decline, p-value = 0.061; and 24% decline, p-value = 0.017, respectively). With lower out-of-pocket payments for hospital care, monthly household spending on personal hygiene rose by 0.9 (p-value = 0.026) and 0.6 US$ (p-value = 0.098) under the expanded insurance and provider payment interventions, respectively, amounting to roughly a 40-60% increase relative to the controls. With the current surge for health insurance expansion in developing countries, our study suggests paying increased and possibly, equal attention to supply-side interventions will have similar impacts with operational simplicity and greater provider accountability.

Ecological range shift in the polyploid members of the South American genus Fosterella (Bromeliaceae).

Background and Aims: The distribution of polyploidy along a relatively steep Andean elevation and climatic gradient is studied using the genus Fosterella L.B. Sm. (Bromeliaceae) as a model system. Ecological differentiation of cytotypes and the link of polyploidy with historical biogeographic processes such as dispersal events and range shift are assessed. Methods: 4',6-Diamidino-2-phenylindole (DAPI) staining of nuclei and flow cytometry were used to estimate the ploidy levels of 159 plants from 22 species sampled throughout the distribution range of the genus. Ecological differentiation among ploidy levels was tested by comparing the sets of climatic variables. Ancestral chromosome number reconstruction was carried out on the basis of a previously generated phylogeographic framework. Key Results: This study represents the first assessment of intrageneric, intraspecific and partially intrapopulational cytotype diversity in a genus of the Bromeliaceae family. In Fosterella , the occurrence of polyploidy was limited to the phylogenetically isolated penduliflora and rusbyi groups. Cytotypes were found to be ecologically differentiated, showing that polyploids preferentially occupy colder habitats with high annual temperature variability (seasonality). The combined effects of biogeographic history and adaptive processes are presumed to have shaped the current cytotype distribution in the genus. Conclusions: The results provide indirect evidence for both adaptive ecological and non-adaptive historical processes that jointly influenced the cytotype distribution in the predominantly Andean genus Fosterella (Bromeliaceae). The results also exemplify the role of polyploidy as an important driver of speciation in a topographically highly structured and thus climatically diverse landscape.