About

Katrina Dlugosch is a Professor in the Department of Ecology and Evolutionary Biology at the University of Arizona, a position she has held since 2025. Her research focuses on the genetics and rapid evolutionary dynamics of ecologically important traits, utilizing a variety of genetic approaches including quantitative, molecular, and genomic methods. Her lab investigates how traits evolve rapidly on human timescales, particularly in invasive species colonizing new locations and native species responding to environmental change. The research aims to understand how genetic and environmental variation translate into phenotypic diversity, adaptation, and changes in ecologically significant traits. Her work combines field ecology, quantitative genetics, genomics, and bioinformatics to explore how traits evolve, how genetic variation is distributed geographically, and how genetic differences influence population dynamics and species distributions.

Research topics

• Evolutionary biology
• Biology
• Ecology
• Sociology
• Demography
• Genetics

Selected publications

• Near chromosome-level genome assembly of <i>Neomusotima conspurcatalis</i> gives insights into the evolution of moth genome architecture and fern–insect interactions

  G3 Genes Genomes Genetics · 2026-03-18

  articleOpen accessSenior author

  Plant-insect interactions are the foundation of ecosystems globally, yet we are still determining the underlying mechanisms through which these relationships evolve. The coevolution 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 undersampled and understudied. Here, we present a near-chromosome-level 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 (i) investigate the relationships among the Crambidae using genome-wide sequences and genome structure and (ii) examine gene family evolution across this phylogeny. Our results reveal highly conserved genome structure across this family of moths, and 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.

  PublisherDOI

• Near chromosome-level genome assembly for the invasive annual forb <i>Centaurea melitensis</i>

  bioRxiv (Cold Spring Harbor Laboratory) · 2026-05-20

  articleOpen accessSenior author

  ABSTRACT Premise Centaurea 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. Methods Inbred 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. Results We 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 . Discussion We provide a highly complete and contiguous genome assembly to facilitate the further study of genomic variation in C. melitensis .

  PublisherOA PDFDOI

• Testing fundamental hypotheses of colonization success in the ferns

  bioRxiv (Cold Spring Harbor Laboratory) · 2026-04-18

  articleOpen accessSenior author

  Abstract Background and Aims Non-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. Methods We 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 Results We 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. Conclusions We 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.

  PublisherOA PDFDOI

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

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-06-17 · 1 citations

  preprintSenior author

  Abstract Aim Nearly 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. Location We 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. Methods We 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. Results We 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 conclusions Our 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.

  PublisherDOI

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

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-09-12 · 1 citations

  preprintOpen accessSenior author

  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. Cluster 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.

  PublisherOA PDFDOI

• The genome of the vining fern <i>Lygodium microphyllum</i> highlights genomic and functional differences between life phases of an invasive plant

  Proceedings of the National Academy of Sciences · 2025-09-25 · 3 citations

  articleOpen access

  Functional and genomic studies on the differences between the gametophyte and sporophyte life phases of plants remain scarce, yet unraveling these dynamics is crucial to understanding the biology of plants and the success of each phase under different conditions. Here, we provide a reference genome for the highly invasive fern Lygodium microphyllum and compare the transcriptomic and epigenomic landscapes of its gametophyte and sporophyte life phases. Under ambient conditions, we found differential regulation and splicing of developmental genes (homeobox and MADS-box clades) may play a role in the genomic determination of the haploid and diploid life stages. We generated a 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. We further explored the physiological and transcriptomic responses of gametophytes and sporophytes to freezing stress, the most likely abiotic factor limiting further range expansion of this invasive species. While controlled by the same genome, we show that life phases and tissues use alternative molecular pathways in response to freezing and greater physiological resilience in the gametophyte life stage to this stressor. Our results underscore the need to incorporate both life phases when developing effective mitigation strategies, as differential responses to environmental stressors between phases reveal opportunities for management approaches (e.g., targeting gametophytes in addition to sporophytes). These genomic resources fill a gap in our understanding of fundamental plant biology and inform invasive species research.

  PublisherOA PDFDOI

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

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-12-19

  articleOpen accessSenior author

  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.

  PublisherOA PDFDOI

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

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-11-10

  preprintOpen accessSenior author

  Abstract 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.

  PublisherOA PDFDOI

• The genome of the vining fern <i>Lygodium microphyllum</i> highlights genomic and functional differences between life phases of an invasive plant

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-03-07 · 1 citations

  preprintOpen access

  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.

  PublisherOA PDFDOI

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

  American Journal of Botany · 2025-06-01 · 3 citations

  articleOpen accessSenior author

  PREMISE: Within plant communities, few species are abundant, and most are locally rare. Worldwide, 36% of plant species are exceedingly rare and often face high extinction risk. However, the community phylogenetic impact of the loss of rare plants is largely unknown in many systems. We address this gap by investigating how rare species contribute to phylogenetic diversity, considering multiple metrics of rarity and multiple elevations in a subalpine plant community. METHODS: We collected abundance data at three sites near the Rocky Mountain Biological Laboratory (Colorado, USA). We calculated each species' range size from public occurrence data. 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. RESULTS: We 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 or groups of rare species than when we removed single common species and groups of common species. CONCLUSIONS: We found that rare species, whether at low abundance or with a small range, do not disproportionately contribute to phylogenetic diversity in our subalpine plant community. These results were consistent across elevations. Instead, rare species might provide phylogenetic redundancy with common species. Deeper understanding of functional differentiation is needed to understand contributions of rare species to this system.

  PublisherOA PDFDOI

Recent grants

• CAREER: Rapid evolution of an invasive plant: the role of microbial interactions

  NSF · $1.1M · 2018–2025

Frequent coauthors

• Loren H. Rieseberg

  University of British Columbia

  22 shared

• Michael S. Barker

  21 shared

• Hannah E. Marx

  University of New Mexico

  13 shared

• Patricia Lu‐Irving

  Royal Botanic Garden Sydney

  11 shared

• F. Alice Cang

  University of Arizona

  11 shared

• Brian J. Enquist

  Santa Fe Institute

  10 shared

• Brittany S. Barker

  Oregon State University

  8 shared

• David A. Baltrus

  8 shared

Awards & honors

• University of Arizona Excellence in Postdoctoral Mentoring A…
• University of Arizona College of Science Distinguished Early…
• National Science Foundation CAREER Award (2018)
• Menzel Award, Best Paper in Genetics, Botany (2006)
• Speaking Award, CA Botanical Society (2005)