Biology subjects

Dlugosch, K. M.

Publications and source records attributed to Dlugosch, K. M..

At least 19 recordsLinked to original sources

bioRxiv2026

Trait differentiation across urbanized environments in invasive Centaurea melitensis is not predicted by the Plant Economic Spectrum

Urbanization imposes unique selective pressures on organisms, but connecting specific urban environmental differences to trait adaptation requires detailed characterization of environmental heterogeneity across urbanized landscapes and tests for adaptation to it, rarely done to date. The Plant Economic Spectrum (PES) predicts that plants invest in different life strategies according to resource availability, ranging from an acquisitive strategy favoring fast growth and aboveground biomass where resources are abundant, to a conservative strategy favoring belowground investment where resources are limiting. Here, we leverage previous work describing the mosaic of urbanized environments in California, USA as a set of Environmental Zones, and use this framework to test for trait differentiation predicted by the PES in the invasive annual plant Centaurea melitensis. Seeds from 31 populations across California were grown in greenhouse conditions for two generations. In the second generation, we measured growth, reproductive, and phenology traits to test for genetically-based differentiation and whether variation follows PES predictions. Variation across all genotypes was not structured along the multivariate trait axes predicted by the PES. Individual traits were associated with environmental variables, including impervious surface cover and tree cover, following some PES expectations, but multi-trait strategies were absent. We found evidence that C. melitensis traits have differentiated genetically across environments with different features of urbanization but did not exhibit the multi-trait strategies predicted by the PES. Our study pairs detailed knowledge of urbanized environments with tests of trait-environment relationships to reveal how urbanization may be selecting on the species that inhabit these spaces.

ecology↗

bioRxiv2026

Mite Genome Miniaturization: Assembly of the biological control agent Floracarus perrepae reveals dynamic genome evolution in eriophyoid mites

The eriophyoid mites (Acari: Eriophyoidea) represent an extreme case of genome streamlining, with genomes averaging just 32Mb, among the smallest of all animals. This clade of mites is highly diverse with more than 4000 species. Their morphologies are specialized for feeding on their host plants, including a simplified worm-like body plan with just two pairs of legs and modified mouth parts that can induce the formation of galls or plant deformities during feeding. Their generally strong host affinities make eriophyoid mites appealing for use as biological control agents, although their short generation times and small genomes could facilitate rapid evolution and impact their efficacy in management programs. Here, we sequenced the genome of the biological control mite Floracarus perrepae, producing a highly contiguous genome totalling just 23.1 Mb, among the smallest of all animals. We also assembled another non-eriophyid mite genome from accidental DNA bycatch (69.4Mb). We placed this new genomic resource in a phylogenetic context to reveal that mites have highly dynamic genome evolution, with a significant trend in genome downsizing in the eriophyoids. Our results suggest that this streamlining is associated with non-genic elements such as the suppression or excision of retrotransposons and purging of introns. As new sequencing techniques become available, novel genomic resources for tiny organisms such as F. perrepae will be more readily accessible, facilitating both fundamental genome evolutionary biology and applied sciences such as biological control programs which use eriophyoid mites for the management of invasive species.

evolutionary biology↗

bioRxiv2026

Near chromosome-level genome assembly for the invasive annual forb Centaurea melitensis

PremiseCentaurea melitensis (Asteraceae) is a problematic invader of grasslands globally, but little is known about its genetic makeup. Here we develop a reference genome to facilitate studies of its invasion history, genetic variation, and evolution. MethodsInbred offspring of a single individual of C. melitensis from its invasion of California, USA were used for flow cytometry to estimate genome size, and for genomic DNA extraction. DNA was sequenced with PacBio HiFi technology (yield = 85.7Gb). The genome was assembled with Hifiasm and annotated with BRAKER3. GENESPACE was used to compare gene order (synteny) with three other species within the subfamily Cichorioideae. ResultsWe estimated a mean genome size of 795.0 Mbp for C. melitensis, and our assembly totaled 696.6 Mbp in 48 contigs (N50 = 55.6 Mbp; BUSCO = 98%), with annotation of 25,157 protein-encoding genes. This included four telomere-to-telomere putative chromosomes, nine additional chromosome arms terminated by telomeric repeats, and a complete chloroplast genome. Synteny varied markedly across the genus and subfamily, suggesting a dynamic history of structural variation in the lineage of C. melitensis. DiscussionWe provide a highly complete and contiguous genome assembly to facilitate the further study of genomic variation in C. melitensis.

genomics↗

bioRxiv2026

Testing fundamental hypotheses of colonization success in the ferns

Background and AimsNon-native species are now ubiquitous members of regional floras. The factors that lead to establishment and dominance of non-native species are continuously debated. Fundamental hypotheses about drivers of invasion success include the role of phylogeny, polyploidy, genome size, and rapid niche evolution. These hypotheses have been tested in the seed plants, but ferns, the second largest group of vascular plants, have rarely been considered in these analyses, despite making up a non-trivial portion of non-native floras. MethodsWe compiled a dataset of global non-native ferns and categorized them along the invasion spectrum using descriptions from the literature and natural history collections. Using this dataset, we assessed I) the taxonomic diversity and phylogenetic clustering of non-native ferns, II) the geographic distribution of fern introductions, testing for shifts in climatic niches, and III) test for the association of invader traits across the invasion continuum, including smaller genome sizes and higher ploidal levels. Key ResultsWe generated a dataset that includes 83 taxa; of these, we classified 18 as casual, 35 as naturalized (but not invasive), and 30 as invasive. Using this dataset, we found I) weak or no phylogenetic clustering of non-native ferns, II) some regions are overrepresented as sources and recipients of introductions, III) climatic niches are often conserved between native and introduced ranges, but can differ between introductions, IV) naturalized ferns have smaller genomes, and V) invaders have higher ploidal levels. ConclusionsWe integrated regional floras, occurrence and climate data, phylogeny, and cytology to test fundamental hypotheses regarding the colonization success of ferns. This study provides insights into the ecological, genomic, and phylogenetic features associated with the colonization of new habitats by non-native ferns, a largely overlooked portion of non-native plant taxa.

evolutionary biology↗

bioRxiv2025

Near chromosome-level genome assembly of Neomusotima conspurcatalis gives insights into the evolution of moth genome architecture and fern-insect interactions

Plant-insect interactions are the foundation of ecosystems globally, yet we are still determining the underlying mechanisms through which these relationships evolve. The co-evolution between insects and their host plants should shape the genomes of both partners, and genes involved in interaction specificity should show unique genomic signatures (e.g., rapid evolution, gene family expansions). Biological control programs are an excellent system for disentangling the genomics and molecular biology of the establishment of an insect and its host plant specificity. Fern-insect relationships are among the most poorly understood, and ferns have long been thought to have few interactions with insects, although recent evidence suggests that these relationships are under-sampled and studied. Here, we present a near-chromosome genome assembly of the crambid moth Neomusotima conspurcatalis, a biological control agent employed in the management of the invasive vining fern Lygodium microphyllum. We use this novel genomic resource to explore the evolution of genome architecture across the Crambidae, revealing highly conserved genome structure across this family of moths. We also examine gene family evolution across the phylogeny and identify expansions in odorant receptor gene families that may be involved in the highly specific interaction of N. conspurcatalis with L. microphyllum. This work highlights the utility of genomics in biological control, and the utility of biological control in informing fundamental understanding of plant-insect interactions. SummaryPlant-insect interactions form the basis of ecological communities and can be highly specific through long lasting co-evolution. Classical biological control provides excellent opportunities to investigate how insect and host genomes are shaped by co-evolutionary processes. We sequenced the genome of Neomusotima conspurcatalis, a biological control moth used to manage the invasive fern Lygodium microphyllum. We analyzed how the structure of the genome has evolved over time relative to other crambid moths and how expansions in gene families involved in odorant reception may be involved in co-evolution with its host. This work provides insight into herbivore interactions in seed-free vascular plants.

evolutionary biology↗

bioRxiv2025

Phylogenetic patterns over sixty-five years of vegetation change across a montane elevation gradient

Phylogenetic diversity is an important axis of biodiversity associated with ecosystem stability and productivity. However, climate change will threaten phylogenetic diversity when extinctions are phylogenetically clustered. Despite the importance of phylogenetic diversity for current and future ecosystems, and the potential unique insights it offers into communities, few studies have quantified its long-term changes. Here, we leverage a dataset spanning approximately 65 years and 1500 m of elevation in the Colorado Rocky Mountains to test for changes in phylogenetic diversity in angiosperm communities. We included four community types (sagebrush, spruce-fir, upland-herb, alpine), which vary in the direction and magnitude of changes in species richness over this period. We tested whether individual species responses to climate change could be predicted by phylogeny, including changes to abundance, constancy (% of sites occupied), and elevational range. We did not find phylogenetic signal in abundance change in any community, but we did find phylogenetic signal in both constancy shifts in alpine and elevational shifts in sagebrush communities. We then tested for changes in phylogenetic diversity across time for each community type. We found that phylogenetic diversity changed in the same direction as species richness in the sagebrush community, where both declined, and in the upland-herb, where both increased, with important roles for both species gains and losses in community phylogenetic composition. The alpine community did not change in phylogenetic diversity, although richness declined, while the spruce-fir community increased in phylogenetic diversity but did not change in richness, emphasizing the potential for changes in different aspects of diversity to be decoupled. Our work highlights that the impacts of climate change vary across communities, and that phylogeny is shaping changes in certain systems. Given the importance of phylogenetic diversity to ecosystem function, long term studies are essential for understanding how climate change impacts phylogenetic diversity in distinct community types with unique responses to climate change.

ecology↗

bioRxiv2025

Applying a classification approach to categorizing urbanized landscapes in California and their invasion by the Maltese starthistle Centaurea melitensis

There is increasing evidence that the traits of organisms can differ in urban environments, but defining what makes an environment urban is difficult. There are many variables associated with increasing human impacts that might be associated with urbanization, and this makes it challenging to identify both how traits vary across diverse urbanized landscapes and the variables that might drive that variation. To better define the mosaic of urban environmental heterogeneity and identify similar types of environments that are comparable across its complexity, here we develop a multivariate landscape classification framework and apply it to classification of land area in the state of California, USA. We used a hierarchical cluster analysis to group 7,829 government census tracts into Environmental Zones based on a set of 19 independent environmental characteristics, including climate, land cover, pollution, and socio-economic variables. This analysis identified nine major Environmental Zones, which were differentiated based upon complex combinations of variables that did not align with conventional urban vs. natural dichotomies or gradients. Environmental Zones also occurred as mosaics of many zones within cities and differed in their relative abundance between cities, reflecting complex urban landscapes unique to each area. We then asked if these Environmental Zones were better able to explain trait variation than conventional urban vs. non-urban classification using a case study of the invasive, annual plant Centaurea melitensis, commonly found throughout much of California. Seeds from seventeen populations of C. melitensis were collected from six Environmental Zones, including two heavily urbanized, and four more natural/agricultural. Seeds were grown in greenhouse conditions, and eight vegetative traits were measured. No trait differed significantly between urban and non-urban sites, but four traits differed according to Environmental Types (length of longest leaf, SLA, root diameter, and the number of flowerheads). Traits differed between the heavily urbanized zones, as well as among the relatively more natural zones. Our results reveal that more complex multivariate classifications of the urban mosaic can identify similar, comparable environments across complex landscapes and better explain trait variation in organisms navigating urbanized environments.

ecology↗

bioRxiv2025

Phylogenetic diversity and species diversity are decoupled under experimental warming and cooling in Rocky Mountain plant communities

AimNearly 8% of species could go extinct from climate change; many organisms are already experiencing declines in abundance, local extinction, and range shifts. How such changes impact community diversity is an open question in most systems. Whether changes in phylogenetic diversity parallel those in traditional diversity metrics is also often unknown. We used experimentally transplanted plant communities to ask how different aspects of community diversity change with environmental factors across elevation, and whether phylogenetic relationships predict individual species responses to change. LocationWe experimentally transplanted subalpine plant communities down and upslope across 400 m of elevation at the Rocky Mountain Biological Laboratory, Gothic, CO, USA, to simulate climate warming and cooling. MethodsWe identified how experimental warming and cooling impacted community diversity by testing for differences in species richness, Shannon diversity, and phylogenetic diversity among transplant treatments. We tested for phylogenetic signal in each species change in percent cover among treatments. Finally, we assessed if aspects of species rarity (and thus their putative extinction risk) predicted post-transplant change independently or in addition to their phylogenetic relationship within the community. ResultsWe found that species richness and Shannon diversity decreased in cooled treatments and increased in some warmed treatments. In contrast, phylogenetic diversity increased in the cooled treatment and did not change in the warmed treatments. Individual species changes in response to warming and cooling were not correlated with phylogeny or aspects of rarity. Main conclusionsOur results suggest that species losses in cooled treatments are phylogenetically dispersed, increasing phylogenetic diversity, even as richness and Shannon diversity decline. Increasing richness and Shannon diversity in warmed treatments suggests that new species from across the phylogeny can colonize after transplantation, leading to stability in phylogenetic diversity under warming at this time scale, with further change likely as extinction debts are paid.

ecology↗

bioRxiv2025

The genome of the vining fern Lygodium microphyllum highlights genomic and functional differences between life phases of an invasive plant

Functional and genomic studies on the differences between gametophyte and sporophyte life phases remain scarce, yet unraveling these dynamics is crucial to understanding the biology of plants and the success of each phase under different environments. Here, we provide a novel reference genome for the highly invasive fern Lygodium microphyllum and compare the transcriptomic and epigenomic landscapes of the gametophyte and sporophyte life phases. We found differential regulation of developmental genes (homeobox and MADS-box clades) and usage of alternative isoforms that may play a role in the genomic determination of the haploid and diploid life stages. We further generated the first base pair-resolution methylome of a fern gametophyte, and determined that methylation patterns are remarkably similar between vegetative tissues despite their morphological and functional differences. By examining the physiological and transcriptomic responses of gametophytes and sporophytes to freezing stress, the most likely abiotic factor preventing further expansion of this invasive species, we show that life phases and tissues use alternative molecular pathways to respond to this stressor, underscoring the need to incorporate both life phases when developing effective mitigation strategies. These new genomic resources fill a gap in our understanding of fundamental plant biology and inform invasive species research. SIGNIFICANCEAll land plants undergo an alternation of generations between haploid gametophyte and diploid sporophyte life phases. How these disparate life phases are generated from a single genome, and the functional implications of these differences for plant success, is largely unknown. Moreover, understanding life-phase-specific differences in rapidly evolving populations, such as invasive species, is critical to developing effective management strategies. We assembled a chromosome-level genome and generated epigenomic and transcriptomic resources from gametophyte and sporophyte phases of the invasive fern Lygodium microphyllum, which is estimated to cost the U.S. more than $2 million annually. We highlight transcriptomic, epigenomic, and physiological variation between life phases and find support for the crucial role of the often overlooked gametophyte in the invasion process.

plant biology↗

bioRxiv2024

Rare species do not disproportionately contribute to phylogenetic diversity in a subalpine plant community

Premise of the studyWorldwide, 36% of all plant species are exceedingly rare, and are at the highest risk of extinction. Extinction risk has also been observed to be phylogenetically clustered, threatening the loss of lineages that contribute unique evolutionary diversity to communities. Rare plants contributions to phylogenetic diversity are largely unknown, however. We investigate whether rare species (as measured by local abundance and range size) contribute disproportionately to phylogenetic diversity in a subalpine plant community. MethodsWe collected abundance data at three sites in Washington Gulch near the Rocky Mountain Biological Laboratory (RMBL, Gothic, Colorado, USA) in 2021 and 2022. We then calculated range size for each species. We calculated phylogenetic signal for abundance and range size, compared community phylogenetic metrics weighted by range size and abundance to unweighted metrics, and quantified the change in phylogenetic diversity when removing single species and groups of species ranked by rarity. Key resultsWe found phylogenetic signal for abundance, but not range size. There was no difference between rarity-weighted and unweighted phylogenetic diversity metrics. Finally, phylogenetic diversity did not decline more when we removed single rare species and groups of rare species than when we removed single common species and groups of common species. ConclusionsOverall, we found that rare species do not disproportionately contribute to phylogenetic diversity. This suggests that rare species likely provide phylogenetic redundancy with common species, and losing rare species may not cause disproportionate drops in phylogenetic diversity in this system.

ecology↗

bioRxiv2024

Chromosome-scale reference genome of Pectocarya recurvata, a species with one of the smallest genome sizes in Boraginaceae

PremisePectocarya recurvata (Boraginaceae), a native species of the Sonoran Desert, has served as an important model system for a suite of ecological and evolutionary studies. Despite its relevance as an eco-evolutionary model, no reference genome assemblies in the Cynoglossoideae subfamily have been published. MethodsUsing PacBio HiFi sequencing, we assembled a reference genome for P. recurvata and annotated coding regions with full-length transcripts from an Iso-Seq transcriptome library. We assessed genome completeness with BUSCO and used flow cytometry and K-mer analysis to estimate the genome size of P. recurvata. ResultsThe chromosome-scale reference genome assembly for P. recurvata was 216.0 Mbp long with a contig N50 of 12.1 Mbp. Our assembly included 12 primary contigs bounded by telomeres at all ends but one, consistent with the 12 chromosomes documented for the species. The chromosomes covered 158.3 Mbp and contained 30,655 predicted genes. Our measured haploid genome size from the same population was 386.5 Mbp, among the smallest for Boraginaceae. Genomic analyses suggested that this may reflect a recent autotetraploid, such that predicted diploid genome size would be even smaller and similar to the assembly size. DiscussionThe P. recurvata assembly and annotation provide a high-quality genomic resource in a sparsely represented area of the Angiosperm phylogeny. Our new genome will enable future ecophysiology, biogeography, and phylogenetics research.

genomics↗

bioRxiv2024

Plant G x Microbial E: Plant genotype interaction with soil bacterial community shapes rhizosphere composition during invasion

It is increasingly recognized that different genetic variants can uniquely shape their microbiomes. Invasive species often evolve in their introduced ranges, but little is known about the potential for microbial associations to evolve during invasion as a result. We investigated invader genotype (G) and microbial environment (E) interactions in C. solstitialis (yellow starthistle), a Eurasian plant that is known to have evolved novel genotypes, and to have altered microbial interactions, in its severe invasion of California, USA. We conducted an experiment in which native and invading genotypes were inoculated with native and invaded range soil microbial communities. We used amplicon sequencing to characterize rhizosphere bacteria in both the experiment and the field soils from which they were derived. We found that bacterial diversity is higher in invaded soils, but that invading genotypes accumulated a lower diversity of bacteria and unique microbial composition in experimental inoculations, relative to native genotypes. Associations with potentially beneficial Streptomycetaceae were particularly interesting, as these were more abundant in the invaded range and accumulated on invading genotypes. Thus variation in microbial associations of invaders was driven by the interaction of G and E, and microbial communities appear to change in composition along with host evolution during invasion.

evolutionary biology↗

bioRxiv2023

Phylogenetic diversity of flowering plants declines throughout the growing season across a subalpine elevational gradient

Phylogenetic diversity is an important axis of biodiversity associated with many ecosystem functions, but its variation over time in temperate communities has rarely been explored. Plants flowering phenology is key for reproduction: it determines synchrony among plants, mutualists, antagonists, and favorable environmental conditions. Individual species flowering phenologies combine to determine which species flowers co-occur in time and space to form co-flowering communities. We recorded plants flowering phenology across elevations in the Colorado Rocky Mountains and predicted: 1) flowering species will form subsets of co-flowering species, 2) groups of co-flowering species will be more distantly related than the broader community, 3) marginal early and late season conditions will constrain flowering to species groups that are less phylogenetically diverse and 4) the entire community will have higher phylogenetic diversity at higher elevations. We identified co-flowering groups using a network analysis and quantified their phylogenetic diversity. Co-flowering communities had higher phylogenetic diversity early in the season and at higher elevations, but became less diverse by all metrics at the end of the season across elevations. Our results indicate that phylogenetic diversity varies consistently across the season and that conditions in the late season and at low elevations might constrain diversity.

ecology↗

bioRxiv2022

Ecological effects of genome size in yellow starthistle (Centaurea solstitialis) vary between invaded and native ranges

Invasive species have become a pervasive threat on every continent and across a broad array of environments. Several traits predicted to promote invasion success, such as small seed size, rapid vegetative growth and short time to reproduction, are correlated with smaller genome sizes in a number of systems. To understand the influence of genome size on plant invasion dynamics, we compared genome sizes and traits in Centaurea solstitialis (YST) genotypes from the Californian invasion to those from their native source region in Spain. We conducted a common garden experiment and genome size survey to ask: (1) Is the invasion associated with genome size reduction? (2) To what extent can differences in genome size explain previously observed increases in plant size and reproduction in YST invasions? (3) Finally, we tested for expected evolutionary patterns in genome size across populations, including evidence of selection favouring reduced genome sizes at higher elevations, and evidence of stochastic processes leading to increases in genome sizes where effective population sizes are smaller. We found a reduction in corrected genome size in the invaded range, as well as significant interaction effects of range x elevation on genome size, and range x genome size on flowering time variation. Specifically, larger genomes tended to flower later and genome size decreased with increasing elevation in the invasion only. These emergent relationships in invading YST suggest potential selection for smaller genomes following introduction of YST to its invaded range. We also found a significant effect of measurement date on genome size estimation by flow cytometry, and this effect was more pronounced among native range genotypes.

evolutionary biology↗

bioRxiv2022

Chromosome-scale reference genome and RAD-based genetic map of yellow starthistle (Centaurea solstitialis) reveal putative structural variation and QTLs associated with invader traits

Invasive species offer outstanding opportunities to identify the genomic sources of variation that contribute to rapid adaptation, as well as the genetic mechanisms facilitating invasions. The Eurasian plant yellow starthistle (Centaurea solstitialis) is highly invasive in North and South American grasslands and known to have evolved increased growth and reproduction during invasion. Here we develop new genomic resources for C. solstitialis and map the genetic basis of invasiveness traits. We present a chromosome-scale (1N = 8) reference genome using PacBio CLR and Dovetail Omni-C technologies, and functional gene annotation using RNAseq. We find repeat structure typical of the family Asteraceae, with over 25% of gene content derived from ancestral whole genome duplications (paleologs). Using an F2 mapping population derived from a cross between native and invading parents, with a restriction site-associated DNA (RAD)-based genetic map, we validate the assembly and identify 13 QTL underpinning size traits that have evolved during invasion. We find evidence that large effect QTL may be associated with structural variants between native and invading genotypes, including a variant with an overdominant and pleiotropic effect on key invader traits. We also find evidence of significant paleolog enrichment under two QTL. Our results add to growing evidence of the importance of structural variants in evolution, and to understanding of the rapid evolution of invaders. Significance StatementInvasive species often evolve rapidly in new environments, potentially informing our understanding of the genomic basis of adaptation, but genomic studies of these non-model systems are limited. We provide a chromosome-scale reference genome, annotation, and genetic map for the invasive plant yellow starthistle, and we investigate the genetic basis of invader trait evolution in this system. We find regions of the genome with large effects on traits that differ between native and invading genotypes, and evidence suggesting genome structural variants and past genome duplications could play a role in rapid adaptation of invading populations. These genomic resources and evolutionary insights aid in our understanding of the sources of genomic variation for adaptation, and how their evolution facilitates invasion.

genomics↗

bioRxiv2022

Genome size variation and evolution during invasive range expansion in an introduced plant

Plants demonstrate some of the greatest variation in genome size among eukaryotes, and their genome sizes can vary dramatically across individuals and populations within species. This genetic variation can have consequences for traits and fitness, but few studies have been able to attribute genome size differentiation to ecological and evolutionary processes. Biological invasions present particularly useful natural laboratories to infer selective agents that might drive genome size shifts across environments and population histories. Here, we test hypotheses for the evolutionary causes of genome size variation across 14 invading populations of yellow starthistle, Centaurea solstitialis, in California, USA. We use a survey of genome sizes and trait variation to ask: (1) Is variation in genome size associated with developmental trait variation? (2) Are genome sizes smaller toward the leading edge of the expansion, consistent with selection for colonizer traits? Or alternatively, does genome size increase toward the leading edge of the expansion, consistent with predicted consequences of founder effects and drift? (3) Finally, are genome sizes smaller at higher elevations, consistent with selection for shorter development times? We found that 2C DNA content varied 1.21-fold among all samples, and was associated with flowering time variation, such that plants with larger genomes reproduced later, with lower lifetime capitula production. Genome sizes increased toward the leading edge of the invasion, but tended to decrease at higher elevations, consistent with genetic drift during range expansion but potentially strong selection for smaller genomes and faster development time at higher elevations.

evolutionary biology↗

bioRxiv2021

Source range phylogenetic community structure can predict the outcome of avian introductions

Competing phylogenetic models have been proposed to explain the success of species introduced to other communities. Here, we present a study predicting the establishment success of birds introduced to Florida, Hawaii, and New Zealand using several alternative models, considering species phylogenetic relatedness to source and recipient range taxa, propagule pressure, and traits. We find consistent support for the predictive ability of source region phylogenetic structure. However, we find that the effects of recipient region phylogenetic structure vary in sign and magnitude depending on inclusion of source region phylogenetic structure, delineation of the recipient species pool, and the use of phylogenetic correction in the models. We argue that tests of alternative phylogenetic hypotheses including the both source and recipient community phylogenetic structure, as well as important covariates such as propagule pressure, are likely to be critical for identifying general phylogenetic patterns in introduction success, predicting future invasions, and for stimulating further exploration of the underlying mechanisms of invasibility.

ecology↗

bioRxiv2020

TagSeq for gene expression in non-model plants: a pilot study at the Santa Rita Experimental Range NEON core site

Premise of the studyTagSeq is a cost-effective approach for gene expression studies requiring a large number of samples. To date, TagSeq studies in plants have been limited to those with a high quality reference genome. We tested the suitability of reference transcriptomes for TagSeq in non-model plants, as part of a study of natural gene expression variation at the Santa Rita Experimental Range NEON core site. MethodsTissue for TagSeq was sampled from multiple individuals of four species [Bouteloua aristidoides and Eragrostis lehmanniana (Poaceae); Tidestromia lanuginosa (Amaranthaceae), and Parkinsonia florida (Fabaceae)] at two locations on three dates (56 samples total). One sample per species was used to create a reference transcriptome via standard RNA-seq. TagSeq performance was assessed by recovery of reference loci, specificity of tag alignments, and variation among samples. ResultsA high fraction of tags aligned to each reference and mapped uniquely. Expression patterns were quantifiable for tens of thousands of loci, which revealed consistent spatial differentiation in expression for all species. DiscussionTagSeq using de novo reference transcriptomes was an effective approach to quantifying gene expression in this study. Tags were highly locus specific and generated biologically informative profiles for four non-model plant species.

plant biology↗