Population Biology Commons^™

Genomic Analysis Reveals New Subspecies Of Cercyonis Scudder, 1875 (Nymphalidae: Satyrinae: Satyrini), Jing Zhang, Qian Cong, Jinhui Shen, Leina Song, Todd L. Stout, Michael S. Fisher, Robb Hannawacker, Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

Genomic analysis of Cercyonis (Cercyonis) Scudder, 1875 (Nymphalidae Rafinesque, 1815) partitions the subgenus into three species groups and reveals five new subspecies from the USA (type localities in parentheses): Cercyonis (Cercyonis) pegala koosharem Stout and Grishin, ssp. n. (Utah, Sevier Co.), Cercyonis (Cercyonis) pegala lasala Grishin, M. Fisher, and Hannawacker ssp. n. (Utah, Grand Co.), Cercyonis (Cercyonis) pegala hortoni Grishin, ssp. n. (Arizona, Gila Co.), Cercyonis (Cercyonis) meadii maculana Grishin, ssp. n. (Colorado, Montezuma Co.), and Cercyonis (Cercyonis) meadii rimana Grishin, ssp. n. (Arizona, Yavapai Co.). A neotype is designated for Satyrus boopis Behr, 1864 (USA, California, Contra Costa Co.). …

Butterfly Taxa Discovery Via Genomic Analysis, Jing Zhang, Qian Cong, Jinhui Shen, Leina Song, Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

Expanding a genomics-guided assessment of butterfly taxonomy, we integrate phylogenetic evidence from all protein-coding genes with morphological considerations to refine our understanding of butterfly systematics and discover new taxa. As a result, 2 subgenera, 39 species, and 5 subspecies are proposed as new (type species in original combinations or type localities are listed in parentheses): Erebia (Magda) magdalena uintana Grishin, ssp. n. (USA: Utah, Uintah Co.) in Nymphalidae Rafinesque, 1815; Myselasia rondea Grishin, sp. n. (Brazil: Rondônia), Myselasia pseudocrinon Grishin, sp. n. (Ecuador: Pastaza), Myselasia paramatuta Grishin, sp. n. (Ecuador: Morona-Santiago), Euselasia anapellos Grishin, sp. n. (Peru: Loreto), …

Adapting Population Genetics, Practice, And Policy For Plant Conservation In A Changing World, Cooper M. Kimball-Rhines

Graduate Doctoral Dissertations

Biodiversity conservation is an inherently interdisciplinary goal that requires effective collaboration among academics, ecosystem managers, policymakers, and other stakeholders. Codesigning research with these groups ensures experiments are useful and improves adoption of policy and practice recommendations while advancing our understanding of basic science. This dissertation explores the power of codesigned research in shaping plant conservation strategies using stakeholder engagement, causal inference, demographic modeling, and multi-omic sequencing techniques. In chapter 1 I discuss the history of New England ecosystems and the need for research-driven changes to plant conservation policy and practice in the face of global change. In chapter 2, I …

Where The Ice Plant Reaches: Mapping Biodiversity Shifts Along Distance Gradients From Carpobrotus Edulis, Leon Hong, Patrick Thomas, Steven Kim, Florybeth La Valle

Seaver College Research And Scholarly Achievement Symposium

This study examined the influence of the invasive ice plant Carpobrotus edulis on species richness and biodiversity in Bluffs Park. Because previous research suggests that C. edulis suppresses nearby native flora, our team used quadrat and transect sampling to measure plant diversity at seven distances from the invasion edge (1 m, 3m, 5m, 10m, 15m, 20m, 30 m). Flora were identified using iNaturalist and recorded. Shannon diversity showed no significant change with distance (ANOVA: F₆,₄₂ = 1.34, p = 0.18), and assumptions of normality and equal variance were met. Tukey’s post-hoc tests found no significant pairwise differences. Community composition based …

Hidden Diversity In A Clonal Endemic: Insights Into Clematis Socialis From A Population Genetics Perspective, Joanna M. Lapoint

Theses

Clematis socialis (Kral) is a rare, federally endangered perennial species restricted to a small number of fragmented populations in Alabama and Georgia. The species exhibits extensive clonality and limited sexual recruitment, characteristics that complicate expectations regarding genetic diversity and population connectivity. Despite its conservation significance, genome-wide assessments of population structure have been lacking. We used genotyping-by-sequencing (GBS) to generate a genome-wide SNP dataset for 170 individuals sampled from six natural populations. Population structure and genetic differentiation were evaluated using Bayesian clustering, analysis of molecular variance (AMOVA), pairwise FST estimates, and network-based visualization. Analyses revealed strong genetic structuring among populations and …

Testing The Intermediate Disturbance Hypothesis On Anthropogenic Pressure In Central Alabama, Gavin Terrell

Theses

Biodiversity is fundamental to maintaining ecosystem structure and function globally. Prior to the late 20th century, ecological theory generally predicted that biodiversity would be highest in systems experiencing minimal disturbance. However, Joseph H. Connell challenged this view with the Intermediate Disturbance Hypothesis (IDH), which posits that species diversity peaks at intermediate levels of disturbance and declines under conditions of both low and high disturbance. Although widely cited, the applicability of the IDH to natural systems remains debated, particularly in the context of anthropogenic disturbances and when diversity is measured beyond species richness alone.

This study evaluated the predictions of the …

Three Butterfly Genera Across The Central Texas Suture Zone, Qian Cong, Jing Zhang, Jinhui Shen, Leina Song, Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

Genome-scale analyses of butterfly specimens across the Central Texas Suture Zone revealed that several taxa currently treated as subspecies exhibit genomic differentiation similar to that observed between species. Further investigation and genomic sequencing of additional specimens from across the ranges of these taxa support this conclusion and result in the following changes to nomenclature and taxonomy. Two new subspecies of Nymphalidae Rafinesque, 1815 are described: Asterocampa louisa monterra Grishin, ssp. n. (type locality in Mexico: Nuevo León) and Asterocampa clyton plana Grishin, ssp. n. (type locality in USA: Texas, Denton Co.). The following taxa are recognized as species, not subspecies: …

A Taxonomic Overview Of The Apodemia Mormo Complex From A Genomic Perspective, Jing Zhang, Qian Cong, Jinhui Shen, Leina Song, Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

Genomic analysis of the Apodemia mormo group (Riodinidae Grote, 1895 (1827)) specimens across the range from southwestern Canada through much of the western USA and northwestern Mexico, complemented by phenotypic examination and photographs of live individuals to inspect eye color, partitions the complex into eight species, one of which is proposed as new: Apodemia (Apodemia) apache Grishin, sp. n. (type locality in USA: Arizona, Apache Co.), and three elevated from subspecies of A. mejicanus: Apodemia (Apodemia) maxima (Weeks, 1891), stat. rest., Apodemia (Apodemia) deserti W. Barnes & McDunnough, 1918, stat. nov., and Apodemia ( …

Impacts Of Native And Nonnative Plant Species On Avian Community Diversity, Matty John Mackay, Steven Van Dang, Brandon Lee Corn

SPARK Symposium Presentations

Avian communities play an essential role in maintaining a healthy ecosystem dynamic by regulating insect populations, assisting in plant pollination, and seed dispersal. These contribute to the overall health of natural ecosystems and mitigate ecological disruptions that would arise in their absence. However, the introduction of non-native invasive plant species can interrupt the balance avian communities bring to ecosystems by reducing availability of food sources, altering habitat structures, increasing competition among individuals, and disrupting ecological relationships through rapid invasion of ecological spaces. Point count observations of birds at Shelby Bottoms Park, Nashville, Tennessee in areas dominated by non-native privet and …

Update To: New Butterfly Taxa And Findings From Genomic Analyses, Jing Zhang, Qian Cong, Jinhui Shen, Leina Song, Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

Due to the United States government shutdown, GenBank services were unavailable, and accession numbers could not be obtained for the sequences reported in the original publication. This update provides the GenBank accession numbers for these sequences, together with additional taxonomic findings accumulated since the initial study. One genus, 16 species and four subspecies are proposed as new (type species or localities in parentheses): Madaga Grishin, gen. n. (Artitropa alaotrana Oberthür, 1916), Udranomia eurianus Grishin, sp. n. (Ecuador: Napo), Entheus dalina Grishin, sp. n. (Brazil: Pará), Entheus ambo Grishin, sp. n. (Colombia: Cauca), Entheus pico Grishin, sp. n. (Colombia: Valle …

New Butterfly Taxa And Findings From Genomic Analyses, Jing Zhang, Qian Cong, Jinhui Shen, Leina Song, Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

Continuing our genomics-driven exploration of butterfly taxonomy, we integrate phylogenetic trees from all protein-coding genes with existing taxonomic and phenotypic knowledge and uncover further insights into butterfly systematics. As a result, one subgenus, 44 species, and 11 subspecies are proposed as new (type species in original combinations or type localities are listed in parentheses): Porphaurea Grishin, subgen. n. (Phoenicops porphyropis Meyrick & Lower, 1902) of Chaetocneme C. Felder, 1860 in Hesperiidae Latreille, 1809; Dione (Agraulis) lamasi Grishin, sp. n. (Peru: Cuzco) in Nymphalidae Rafinesque, 1815; Lasaia (Lasaia) chiapis Grishin, sp. n. (Mexico: Chiapas), Lasaia …

Update To: Advancing Butterfly Systematics Through Genomic Analysis, Jing Zhang, Qian Cong, Jinhui Shen, Leina Song, Nick Grishin

The Taxonomic Report of the International Lepidoptera Survey

In this update, we propose (type species or type localities in parentheses): Lochris Grishin, nom. nov. (Lasaia oileus Godman, 1903; Lepidoptera: Riodinidae) as a new substitute name for Locris Grishin, 2025 preoccupied by Locris Stål, 1866 (Cercopis rubra Fabricius, 1794; Hemiptera: Cercopidae), 5 new species, and 5 new subspecies: Emesis (Mandania) mandarina Grishin, sp. n. (Brazil: Santa Catarina) and Emesis (Mandania) mandela Grishin, sp. n. (Venezuela, Carabobo) in Riodinidae Grote, 1895 (1827); others in Hesperiidae Latreille, 1809: Telegonus (Rhabdoides) flavifimbro Grishin, sp. n. (Colombia), Urbanus (Urbanoides) dolus Grishin, sp. n. (Colombia: …

Advancing Butterfly Systematics Through Genomic Analysis, Jing Zhang, Qian Cong, Jinhui Shen, Leina Song, Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

Within the framework of an ongoing comparative genomic study of global butterfly diversity, we construct phylogenetic trees combining all protein-coding genes assembled from the whole genome shotgun data. When viewed in the context of current taxonomy and phenotypic knowledge, the genome-wide phylogeny points to further advances in butterfly systematics, which are presented here. We assign major clades with comparable levels of genetic divergence to the same taxonomic rank and apply criteria involving relative population divergence and gene flow to define species boundaries. As a result, one genus, 13 subgenera, 62 species, and five subspecies are proposed as new (type species …

Pollinator Plant Communities Within Restored Montane Longleaf Pine Ecosystems, Hanen Van Rossem

Master's Theses

Historically the fire-dependent and biodiverse longleaf pine (Pinus palustris) ecosystem was the dominant ecosystem of the Southeastern US. This ecosystem’s range was massively reduced due to land conversion and fire exclusion, causing the decline of many native species. Efforts to restore and protect longleaf pine stands are now ongoing with the goal of expanding habitat and refuge for threatened species. Differences in restoration practices and prior land use may influence the extent to which restored habitat patches can support pollinators and their plants. This study compared pollinator plant biodiversity between restored neighboring montane longleaf pine stands that differed in …

Notable Hesperiidae Collected By Kilian Roever In Arizona, Usa, Jing Zhang, Qian Cong, Jinhui Shen, Leina Song, Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

Genomic analysis of Hesperiidae specimens collected by Kilian Roever in Arizona, USA, and deposited in the McGuire Center for Lepidoptera and Biodiversity (Florida Museum of Natural History, Gainesville, Florida, USA) confirms several published state species records, reveals that Cecropterus (Murgaria) markwalkeri Grishin, 2023, Telegonus (Telegonus) misitra (Plötz, 1881), and Epargyreus cruza Evans, 1952 have been found in Arizona with sequenced specimens representing first confirmed USA records of these three species, and allows us to discover new taxa Cecropterus (Murgaria) roeveri Grishin, sp. n. and Lerema (Lerema) ochrius occidus Grishin, ssp. n. This …

New Taxa Of Butterflies Supported By Genomic Analysis, Jing Zhang, Qian Cong, Jinhui Shen, Leina Song, Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

Continuing with the genomic analysis of butterflies, we present a taxonomic update. As a result of this work, 3 genera, 6 subgenera, 16 species, and 2 subspecies are described as new. New genera and subgenera are (type species in parenthesis): Systasia Grishin, gen. n. (Hesperia zampa W. H. Edwards, 1876) and Asysta Grishin, gen. n. (Systasea microsticta Dyar, 1923) in Pyrgini Burmeister, 1878 and Alyco Grishin, gen. n. (Styriodes quota Evans, 1955) in Moncina A. Warren, 2008; Ocynthus Grishin, subgen. n. (Ocybadistes hypomeloma Lower, 1911) of Potanthus Scudder, 1872, Arrhona Grishin, subgen. n. (Padraona tranquilla …

Taxonomic Advances Driven By The Genomic Analysis Of Butterflies, Jing Zhang, Qian Cong, Jinhui Shen, Leina Song, Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

This study presents new findings based on a large-scale analysis of butterfly genomic sequences. Focusing on species identification through comparative genomics, we define subspecies as populations differentiated to a lesser extent than distinct species ("species in the making"). Additionally, we propose further adjustments to the current butterfly classification. As a result, 3 subgenera, 12 species, and 4 subspecies are described as new. New subgenera are (type species in parenthesis): Hyalaus Grishin, subgen. n. (Papilio epidaus E. Doubleday, 1846) of Eurytides Hübner, [1821] (Papilionidae Latreille, [1802]) and Astria Grishin, subgen. n. (Lycaena astraea Freyer, 1851) of Glaucopsyche Scudder, 1872 …

Genomic Analysis Reveals New Species And Subspecies Of Butterflies, Jing Zhang, Qian Cong, Jinhui Shen, Leina Song, Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

Large-scale genomic sequencing of butterfly taxa reveals new findings that are presented here. While we focus on detecting species by comparative genomics and define subspecies as groups of populations genetically differentiated from each other but not as strongly as species (that is, subspecies as species in the making), we report other adjustments to butterfly classification. As a result, 4 subgenera, 11 species, and 6 subspecies are proposed as new. New subgenera are: Rapis Grishin, subgen. n. (type species Papilio rapae Linnaeus, 1758, genus Pieris Schrank, 1801) in Pieridae Swainson, 1820 and Callitera Grishin, subgen. n. (type species Eurygona? pulcherrima …

Reassessment Of Amblyscirtes Hegon (Hesperiidae) As A Complex Of Four Distinct Species Revealed By Genomic Analysis, Harry Pavulaan, Ricky Patterson, Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

After the discovery of a unique phenotype in the southern United States with a different ventral ground color than nominotypical Amblyscirtes hegon (Scudder, 1863), which occurs in the northeastern United States, genomic analysis revealed that A. hegon is a species complex. Phenotypic, genitalic, and genomic differences of the complex are presented here. Four species are identified: A. hegon; A. nemoris (W. H. Edwards, 1864), stat. rest.; A. matheri Patterson, Pavulaan & Grishin, sp. n. (TL: USA, Mississippi, Warren County); and A. gelidus Grishin, Patterson & Pavulaan, sp. n. (TL: USA, Michigan, Van Buren County).

Species Richness Of Moths In Parks Surrounded By Varying Levels Of ​Urbanization Around Nashville, Tennessee, Maxwell Stone, Allie Bennett

Science University Research Symposium (SURS)

Moths can act as indicators of environmental wellness due to their pollution sensitivity and the complexity of biodiversity required to support their life cycles. Urbanization can impact the occurrence of moths in protected green spaces. Higher moth species richness was hypothesized to occur in parks surrounded by more rural areas. Three metropolitan parks were chosen in the Nashville area: downtown, within a suburban neighborhood, and in a rural area. Tree canopy cover and degree of impervious surfaces were assessed for each park and surrounding area using iTreeCanopy. Moths were attracted to a white sheet using a mercury vapor bulb, UV …

Butterfly Classification And Species Discovery Using Genomics, Jing Zhang, Qian Cong, Jinhui Shen, Leina Song, Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

Genomic sequencing of worldwide butterfly fauna followed by phylogenetic analysis of protein-coding genes informs butterfly classification throughout the taxonomic hierarchy, from families to species. As a rule, we attribute the same taxonomic rank to more prominent clades of comparable divergence (that is, at the same level in the tree). For species delimitation, we use criteria based on relative genetic differentiation and the extent of gene exchange between populations. We analyze the current taxonomic classification of butterflies in the light of genomic phylogenies and encounter clades that correspond to yet unnamed taxa. As a result, 11 tribes, 33 subtribes, 2 genera, …

Factors Affecting California Grassland Biodiversity: Two Case Studies, Nora Bales

Master's Theses

Biodiversity loss over the last century has been significant and is projected to increase. Biodiversity loss is accelerating due to climate change and habitat loss and degradation. Biodiversity supports key ecosystem services including pollination services, climate regulation, and water filtration. Biodiversity conservation is a top priority for land managers and researchers, however many ecological studies with practical applications lack a thorough understanding of the soil environment in their study system. We conducted two case studies integrating soil and plant data to answer management questions. The first case study investigated the relationship between a threatened plant, Hooveria purpurea var. purpurea and …

Do Species Matter? Examining The Niche Of White Ash (Fraxinus Americana L.) And Estimating Potential Subcanopy Effects Of Its Loss In North-Temperate Forests, Elizabeth Anne Studer

Dartmouth College Ph.D Dissertations

To understand the downstream consequences of the extinction of a species, we must understand its role in an ecosystem. With the impending extirpation of ash (Fraxinus spp.) due to the invasive emerald ash borer (Agrilus planipennis), understanding the role of ash trees is critical to predicting whether its loss will precipitate further species declines and/or ecosystem functions. We evaluated whether subcanopy microbial, invertebrate, and floral communities under four tree species (white ash, American beech, yellow birch, sugar maple) and on two soil hydropedological types (Bh podzol and Typical podzol) varied in species richness, composition, and functional traits in a factorial …

Taxonomic Discoveries Enabled By Genomic Analysis Of Butterflies, Jing Zhang, Qing Cong, Jinhui Shen, Leina Song, Riley J. Gott, Pierre Boyer, Crispin S. Guppy, Steve Kohler, Gerardo Lamas, Paul A. Opler, Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

The comparative genomics of butterflies yields additional insights into their phylogeny and classification that are compiled here. As a result, 3 genera, 5 subgenera, 5 species, and 3 subspecies are proposed as new, that is, in Hesperiidae: Antina Grishin, gen. n. (type species Antigonus minor O. Mielke, 1980), Pompe Grishin and Lamas, gen. n. (type species Lerema postpuncta Draudt, 1923), and Curva Grishin, gen. n. (type species Moeris hyagnis Godman, 1900); in Lycaenidae: Fussia Grishin, subgen. n. (type species Polyommatus standfussi Grum-Grshimailo, 1891) and Pava Grishin, subgen. n. (type species Thecla panava Westwood, 1852); in Hesperiidae: Monoca Grishin, subgen. n. …

Wild Bees Respond Differently To Sampling Traps With Vanes Of Different Colors And Light Reflectivity In A Livestock Pasture Ecosystem, Roshani S. Acharya, Joan M. Burke, Timothy Leslie, Kelly Loftin, Neelendra K. Joshi

Entomology Faculty Publications and Presentations

Wild bees are important pollinators and monitoring their abundance and diversity is necessary to develop conservation protocols. It is imperative to understand differences in sampling efficiency among different trap types to help guide monitoring efforts. This study used a new vane trap design to collect bees in a livestock pasture ecosystem and examined the impact of six different vane colors on wild bee sampling. We recorded 2230 bees comprising 49 species and five families. The most abundant species were Augochlorella aurata (25.8%), Lasioglossum disparile (18.3%), Lasioglossum imitatum (10.85%), Agapostemon texanus (10.8%), Melissodes vernoniae (9.9%) and Halictus ligatus (4.7%). Traps with …

Checking The Checkered Taxonomy Of Plötz's Checkered Skippers (Hesperiidae: Pyrgini), Jing Zhang, Qing Cong, John M. Burns, Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

We present an analysis of the names proposed by Carl Plötz in 1884 for the New World species in the genus Pyrgus Hübner, [1819] facilitated by the genomic sequencing of extant primary type specimens comparatively with a larger sample of more recently collected specimens of these species and their relatives. The changes to nomenclature suggested here are only caused by the identity of primary type specimens as revealed by their phenotypes or though genomic sequencing. All neotypes are designated to stabilize nomenclature in agreement with the current usage of these names, which in unison agrees best with the information available …

Genomic Dna Sequencing Reveals Two New North American Species Of Staphylus (Hesperiidae: Pyrginae: Carcharodini), Jing Zhang

The Taxonomic Report of the International Lepidoptera Survey

Two new skipper butterfly (Hesperiidae) species are described from the United States: Staphylus floridus Grishin, sp. n. (type locality in Florida, Volusia County) and Staphylus ecos Grishin, sp. n. (type locality in Texas, Brewster County). They are cryptic and hence escaped recognition. They differ from their sister species by the relative size and morphology of genitalia and by genotype—including and beyond the COI barcode—thus, suggesting genetic isolation that argues for their species-level status. A lectotype is designated for Helias ascalaphus Staudinger, 1876. Staphylus opites (Godman & Salvin, 1896), stat. rest. is a species-level taxon and not a synonym of Staphylus …

Life After Death – Does Carcass Biodiversity Scale With Carcass Body Size?, Troy Warfield

Biological Sciences Undergraduate Honors Theses

Mammals play a large role in the ecosystems where some, especially large-bodied mammals, act as ecosystem engineers. Mammal carcasses, particularly those of large body mass act as a temporary island of dense nutrients that support other organisms, including other mammal species, for an extended period. Research in this field currently focuses on the link between mammal carcass size and nutrient availably or on non-mammalian size and biodiversity, but little is available on the correlation between mammal carcass size and its influence on ecosystem biodiversity. Here we ask, does the available biomass (i.e., body size) of the carcass affect its role …

Two New Species Of Hermeuptychia From North America And Three Neotype Designations (Nymphalidae: Satyrinae), Qian Cong, Eduardo P. Barbosa, Mario A. Marín, André V. L. Freitas, Gerardo Lamas, Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

Abstract

Two new species of Hermeuptychia Forster, 1964 are described. Hermeuptychia sinuosa Grishin, sp. n. (type locality Guatemala: El Progreso, Morazán) is an isolated member of the genus that does not readily fit into known species groups, as suggested by its distinct male and female genitalia and COI DNA barcode sequences. It is distinguished from its congeners by prominently wavy submarginal lines, rounder wings and distinctive genitalia, and can typically be identified by a white dot, instead of an eyespot, near the ventral hindwing apex. Hermeuptychia occidentalis Grishin, sp. n. (type locality Mexico: Guerrero, Acapulco) belongs to the Hermeuptychia sosybius …

Interspersed Denuded Zone (Idz): How Patchy Leaf Litter Dynamics In A Buckthorn-Invaded Urban Woodland Can Affect Microarthropod Species Richness, Angela Stenberg

DePaul Discoveries

Biodiversity loss may serve as a key diagnostic of the Anthropocene. An important driver of this loss is by means of invasive species. In this study of a forest preserve in Chicago, Illinois we examined Interspersed Denuded Zones (IDZs for short), which are areas of patchy leaf litter in invaded forests caused in this case by the rapid decomposition of litter from buckthorn (Rhamnus cathartica). We characterized the leaf litter mass in IDZs and enumerated litter-inhabiting microarthropod populations. We found that plots of high buckthorn density are associated with IDZs: there was significantly less leaf litter mass in …