Factors determining diversity of saproxylic arthropods in the fruiting bodies of the birch polypore fungus (Fomitopsis betulina)

Factors determining diversity of saproxylic arthropods in the fruiting bodies of the birch polypore fungus (Fomitopsis betulina) | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Short Report Factors determining diversity of saproxylic arthropods in the fruiting bodies of the birch polypore fungus (Fomitopsis betulina) Craig Perl, Simon Leather This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6734571/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 18 Aug, 2025 Read the published version in BMC Research Notes → Version 1 posted 18 You are reading this latest preprint version Abstract Objective: Certain basidiomycete fungi produce semi-stable fruiting bodies, known as brackets, that support a significant quality of saproxylic invertebrate biodiversity, especially in northern forests. The objective of this investigation was to assess the drivers of saproxylic diversity within the fruiting bodies of Fomitopsis betulina. We explore which factors are significant determinants of arthropod diversity and abundance, examining the effects of sporocarp size, height above the ground, and relative isolation from neighbouring sporocarps. Results: We find that larger sporocarps support a greater number of saproxylic arthropods, but diversity and species richness are determined by distance from nearest neighbour. Bracket fungi polypore saproxylic biodiversity forest biological islands sporocarp insect arthropod Figures Figure 1 Figure 2 Introduction Fruiting bodies of some basidiomycete fungi, colloquially called bracket fungi, function as important microhabitats for saproxylic insects and other arthropods, which utilise these sporocarps as food sources, hunting grounds and for physical shelter [ 1 , 2 ]. The importance of bracket fungi fruiting bodies for saproxylic arthropods, has driven investigation into the factors that might influence diversity and distribution among sporocarps. There is evidence that fruiting bodies can act as biological islands (or island-like systems [ 3 ]) for invertebrates [ 4 – 6 ], with sporocarp size [ 5 , 6 ] and nearest neighbour distance found to affect colonisation, abundance and diversity [ 7 ]. Alongside sporocarp size and nearest neighbour distance, other variables such as microclimate [ 6 ], fungal species [ 1 , 8 ] and degree of sporocarp decomposition [ 9 ] have been explored as determinates of saproxylic species distribution and richness. Bracket microclimate, also thought an important determinant of saproxylic diversity, has been found to be affected by height above the ground [ 5 , 10 ]. Though brackets provide resources to invertebrates independent of their species (such as physical shelter), it has been demonstrated that phylogenetically and ecologically associated brackets on the same tree or log support different invertebrate communities [ 1 , 8 ], indicating that there is a degree of specificity to interactions, which may be mediated by texture [ 11 ] and endogenous biochemistry [ 10 ]. We used the fruiting bodies of Fomitopsis betulina , a common polypore of birch trees, to generate pilot data on which factors may contribute to arthropod diversity within this system. We found that arthropod abundance increases only with bracket size, and diversity and species richness decrease with increased fruiting body isolation. Materials and Methods i. Sporocarp collection Eighteen sporocarps from fourteen woodpiles were collected from Ercall Wood, Shropshire, UK 2013/06/16 using random stratified sampling, ensuring collection of sporocarps of a range of sizes. Ercall Wood is a steep, mixed broad-leaf forest with a maximum elevation of 265m (Fig. 1). To avoid confounds from decomposition stage; only sporocarps that were over one year old and less than two years old ( i.e. sporocarps from the previous year’s growing season) were collected. The collected sporocarps correspond to between stages 2 and 3 in [12] and stage 3 in [13]. On collection, the height of the sporocarp above the ground, measured as the distance between the soil surface and the lowest point of the sporocarp, was recorded to the nearest centimetre. The number of brackets present on the dead wood were also documented, as was the location of the next nearest F. betulina bracket on a different log. Only fruiting bodies GPS coordinates were used to establish nearest neighbour distances. The haversine formula tool [14] provided a straight-line distance between two GPS coordinates to the nearest 1 cm. GPS coordinates were recorded using “GPS Location” application (cop-apps.net) installed on a Samsung SIII-mini smartphone. Brackets were collected by hand, wrapped in newspaper and stored in re-sealable plastic bags. ii. Sporocarp volume To measure volume, each sporocarp was placed into a re-sealable plastic sandwich bag from which all the air was expelled. Depending on the size of the bracket, the sporocarp was submerged into a bucket, a 500 ml beaker or a glass tumbler. Each container was filled to the brim with water to ensure maximum displacement. The total volume displaced by the sporocarp was caught in a tray and then measured to the nearest 5ml. iii. Invertebrate identification Sporocarps were dissected using a scalpel under dissecting binocular microscope. Invertebrates were extracted using fine forceps and a paintbrush before being sacrificed in and stored in 80% ethanol before being sorted into morphospecies (Table S1). iv. Diversity Arthropod abundance, species richness and diversity were recorded from each individual bracket. Diversity was calculated using the Shannon-Wiener index (H’): Where p i = the proportion of the total individuals belonging to the i th species. Analysis was conducted on the effective number of species being a more accurate measure of true diversity and permitting comparisons across diversity indices [15]: v. Statistics All statistics were conducted using R v.4.4.0 [16]. Maximal models were initially fitted followed by step-wise elimination of non-significant terms to arrive at the minimum adequate model. Generalised linear models (GLM) and model simplification were all conducted using the R base package. Maximal models were fitted using the following explanatory variables with no interaction terms; log sporocarp volume; nearest sporocarp neighbour; number of other sporocarps at the same log pile; sporocarp height above the ground. Model term significance was assessed using an F-test implemented via the function ‘drop1’, non-significant model terms were eliminated until a minimum adequate model was obtained. Abundance and species richness were overdispersed count data and were therefore modelled using a quasipoisson distribution. Effective number of species presented non-normally distributed residuals and were therefore modelled using a gamma distribution. Results and Discussion We found that sporocarp size was a significant predictor of arthropod abundance (Fig. 2 A; GLM, F 1,18 = 5.29, p = 0.035), larger sporocarps supported a greater number of individuals; in concordance with other investigations into saproxylic biodiversity [ 5 , 6 ]. Only nearest sporocarp neighbour was a significant predictor of species richness (Fig. 2 B; GLM, F 1,18 = 7.70, p = 0.014) and saproxylic diversity (Fig. 2 C; GLM, F 1,18 = 7.70, p = 0.014); both richness and diversity decreased with increasing distance to nearest neighbour [ 10 ]. The height of the sporocarp above the soil and the number of sporocarps present on the same piece of dead wood had no significant effect on arthropod abundance, species richness or diversity (GLM, F 1,18 0.14). These results in part support the concept that bracket fungi sporocarps operate as biological islands; where species richness and diversity may decrease with increased distance to their nearest neighbour. Island biogeography theory also predicts that larger ‘islands’ will support greater diversity, in line with general species-area affects; increased area (or volume, in this instance) predicted to support greater diversity by providing a wider range of ecological niches that can be exploited [ 17 ]. Different sized F. betulinus sporocarps may provide varying niches; they can be heterogeneous in texture [ 11 ], features that could be differentially exploited by specific mycophagous or visiting species. Distance from nearest neighbour may be less relevant to winged groups that can disperse distances greater than the study area, but some groups ( e.g. Carabidae) are not mycophagous and may be utilising sporocarps for hunting or for physical shelter. Other studies found that height above the soil, an indicator of microclimate [ 6 ], a factor not a significant variable in our analysis. We also did not find a relationship between sporocarp size and effective number of species (an indicator of diversity), contrasting with other investigations [ 4 – 6 ]. Our data may differ from previous results due to differences in focal fungal species and the size therein of the fruiting bodies or due to differences in saproxylic species ( e.g. size-diversity relationships may only for Coleoptera [ 5 , 6 ]. Limitations The most significant limitation to this work is the small number of F. betulina fruiting bodies that were collected. To draw stronger conclusions regarding the data collected, a much greater sample size, preferably sampling over a wider geographic area would be needed. Additionally, sampling over a longer period would provide a better indication of the variability of saproxylic species utilising these sporocarps, as would rearing insects from the fruiting bodies rather than dissecting them. The lack of genus or species level identification, rather than morphospecies, is also a limitation on these results. Abbreviations No applicable. Declarations Ethics approval and consent to participate The animals sacrificed during this experiment are not subject to any legal or formal ethical oversight. However, care was taken during animal handling to minimise stress and avoid injury. Animal sacrifice was designed to be as rapid as possible while preserving specimens for identification. · Consent for publication Not applicable · Availability of data and materials The datasets generated and/or analysed during the current study are available in the Open Science Foundation repository, doi.org/10.17605/osf.io/vewj8 · Competing interests The authors declare that they have no competing interests. · Funding Resources were provided to CDP via Harper Adams University MSc Entomology course. · Authors' contributions CDP and SRL conceptualized the project and designed methodology. CDP conducted formal analysis, investigation, visualisation, writing of original draft, and editing. SRL was responsible for funding acquisition, project administration, providing resources, and supervision. · Acknowledgements We would like to extend thanks to Roy Mantle of the Shropshire Mycological Society for advice on sampling site selection and to Glenda Orledge for sharing her knowledge of and enthusiasm for bracket fungi and saproxylic invertebrates. Thanks also to Meghan Barrett and an anonymous referee for insightful comments on this manuscript. · Authors' information (optional) Not applicable References Komonen A. Hotspots of Insect Diversity in Boreal Forests. Conservation Biology. 2003;17:976–81. Kadowaki K. Wood-decaying Fungi and Beetles, a multilateral approach to studying fungus –insect communities. University of Auckland; 2010. Itescu Y. Are island-like systems biologically similar to islands? A review of the evidence. Ecography. 2019;42:1298–314. O’Connell T, Bolger T. Fungal Fruiting Bodies and the Structure of Fungus-Micro-Arthropod Assemblages. Biology and Environment: Proceedings of the Royal Irish Academy. 1997;97B:249–62. Thunes KH, Midtgaard F, Gjerde I. Diversity of Coleoptera of the bracket fungus Fomitopsis pinicola in a Norwegian spruce forest. Biodivers Conserv. 2000;9:833–52. Selonen VAO, Ahlroth P, Kotiaho JS. Anthropogenic disturbance and diversity of species: polypores and polypore-associated beetles in forest, forest edge and clear-cut. Scand J For Res. 2005;20:49–58. Jonsell M, Nordlander G, Jonsson M. Colonization Patterns of Insects Breeding in Wood-Decaying Fungi. J Insect Conserv. 1999;3:145–61. Komonen A. Structure of insect communities inhabiting old-growth forest specialist bracket fungi. Ecol Entomol. 2001;26:63–75. Gdula AK, Konwerski S, Olejniczak I, Rutkowski T, Skubała P, Zawieja B, et al. The role of bracket fungi in creating alpha diversity of invertebrates in the Białowieża National Park, Poland. Ecol Evol. 2021;11:6456–70. Jonsell M, Nordlander G, Ehnström B. Substrate Associations of Insects Breeding in Fruiting Bodies of Wood-Decaying Fungi. Ecological Bulletins. 2001;:173–94. Paviour-Smith K. The Fruiting-Bodies of Macrofungi as Habitats for Beetles of the Family Ciidae (Coleoptera). Oikos. 1960;11:43–71. Krasutskii B V. Beetles (Coleoptera) associated with the birch fungus Piptoporus betulinus (Bull.: Fr.) P. Karst. (Basidiomycetes, Aphyllophorales) in forests of the Urals and Transurals. Entomological Review 2006 86:8. 2006;86:889–900. Graves RC. Ecological Observations on the Insects and Other Inhabitants of Woody Shelf Fungi (Basidiomycetes: Polyporaceae) in the Chicago Area. Ann Entomol Soc Am. 1960;53:61–78. Veness C. Latitude/longitude spherical geodesy tools. 2012. www.movable-type.co.uk/scripts/latlong.html. Jost L. Entropy and diversity. Oikos. 2006;113:363–75. R Core Team. R: A Language and Environment for Statistical Computing. 2024. Matthews TJ, Triantis K. Island biogeography. Current Biology. 2021;31:R1201–R1207. Additional Declarations No competing interests reported. Supplementary Files TableS1morphospecies.csv Table S1: List of morphospecies identified from sporocarps. Cite Share Download PDF Status: Published Journal Publication published 18 Aug, 2025 Read the published version in BMC Research Notes → Version 1 posted Editorial decision: Revision requested 14 Jul, 2025 Reviews received at journal 12 Jul, 2025 Reviews received at journal 04 Jul, 2025 Reviewers agreed at journal 03 Jul, 2025 Reviews received at journal 03 Jul, 2025 Reviews received at journal 02 Jul, 2025 Reviews received at journal 02 Jul, 2025 Reviewers agreed at journal 02 Jul, 2025 Reviewers agreed at journal 02 Jul, 2025 Reviewers agreed at journal 26 Jun, 2025 Reviewers agreed at journal 26 Jun, 2025 Reviewers agreed at journal 25 Jun, 2025 Reviewers agreed at journal 24 Jun, 2025 Reviewers invited by journal 24 Jun, 2025 Editor invited by journal 28 May, 2025 Editor assigned by journal 28 May, 2025 Submission checks completed at journal 28 May, 2025 First submitted to journal 23 May, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6734571","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Short Report","associatedPublications":[],"authors":[{"id":476174367,"identity":"d2cc07c2-36b1-451c-88d7-a4a10abe2318","order_by":0,"name":"Craig Perl","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA7UlEQVRIie3RsYoCMRCA4ZFAthnZdhZkfYURQfFtYnO1YGN3B1vY+AALvoQgWGdJYbNYK8hxh2Ad8QqLK25zipXELS3yFwkJfJAwAKHQi6b/10hUO19vGh+1iJAKdF1yTSDf8BMSz8138QP7tJ/h+WxHnxBPtUxyD6HNG5sWHLst01yR5jFQqWSy8BBGYENghrlorqq/KIAtyOTLSyLryHsu8GAdaT8nyIUFo0ggkCPsiO9hVOLIAB87uZA9KllhpxxmA9/341m0PF0m+zZF2cFOflWark2xm3mIq5qIvh+w1iAbl/sMQ6FQKPSgP75rSj6oWu+lAAAAAElFTkSuQmCC","orcid":"","institution":"University of Stirling","correspondingAuthor":true,"prefix":"","firstName":"Craig","middleName":"","lastName":"Perl","suffix":""},{"id":476174368,"identity":"54180d89-40e0-4d9a-b84e-dc01e354e7f6","order_by":1,"name":"Simon Leather","email":"","orcid":"","institution":"Harper Adams University","correspondingAuthor":false,"prefix":"","firstName":"Simon","middleName":"","lastName":"Leather","suffix":""}],"badges":[],"createdAt":"2025-05-23 16:38:09","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6734571/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6734571/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s13104-025-07434-6","type":"published","date":"2025-08-18T16:29:45+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":85494364,"identity":"ccbacd08-faf2-4150-849f-413dac8b292d","added_by":"auto","created_at":"2025-06-26 13:35:34","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":904088,"visible":true,"origin":"","legend":"\u003cp\u003eField site location. \u003cstrong\u003e1A:\u003c/strong\u003e Ercall Wood, Shropshire in the west of England, approximately 52°41'18\"N, 2°31'19\"W. \u003cstrong\u003e1B: \u003c/strong\u003eLocation of deadwood from which sporocarps were collected. Multiple sporocarps were collected from some dead wood locations.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6734571/v1/42deba4a56f98361be0b3ee2.png"},{"id":85495352,"identity":"680c5731-d915-489f-922a-739b7b843935","added_by":"auto","created_at":"2025-06-26 13:43:34","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":171285,"visible":true,"origin":"","legend":"\u003cp\u003eArthropod abundance, species richness and diversity within \u003cem\u003eFomitopsis betulinua \u003c/em\u003esporocarps. \u003cstrong\u003e2A:\u003c/strong\u003eArthropod abundance increases with increasing sporocarp volume. \u003cstrong\u003e2B: \u003c/strong\u003eSpecies richness decreases within a sporocarp with increasing distance from the next nearest sporocarp. \u003cstrong\u003e2C: \u003c/strong\u003eEffective number of species within a sporocarp decreases with increasing distance from the next nearest sporocarp.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-6734571/v1/6fdaf77cf0f5e9d9f8b64375.png"},{"id":89847337,"identity":"2b64e0e1-4642-48ca-a35f-44ad2ca9f589","added_by":"auto","created_at":"2025-08-25 16:43:15","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1343386,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6734571/v1/d060a242-0573-44f4-b818-ef87acced400.pdf"},{"id":85495351,"identity":"5d5d052b-255a-4f59-a44c-2cf1305c6f53","added_by":"auto","created_at":"2025-06-26 13:43:34","extension":"csv","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":1774,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eTable S1: \u003c/strong\u003eList of morphospecies identified from sporocarps.\u003c/p\u003e","description":"","filename":"TableS1morphospecies.csv","url":"https://assets-eu.researchsquare.com/files/rs-6734571/v1/288b52cd566622d8223703f3.csv"}],"financialInterests":"No competing interests reported.","formattedTitle":"Factors determining diversity of saproxylic arthropods in the fruiting bodies of the birch polypore fungus (Fomitopsis betulina)","fulltext":[{"header":"Introduction","content":"\u003cp\u003eFruiting bodies of some basidiomycete fungi, colloquially called bracket fungi, function as important microhabitats for saproxylic insects and other arthropods, which utilise these sporocarps as food sources, hunting grounds and for physical shelter [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. The importance of bracket fungi fruiting bodies for saproxylic arthropods, has driven investigation into the factors that might influence diversity and distribution among sporocarps. There is evidence that fruiting bodies can act as biological islands (or island-like systems [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]) for invertebrates [\u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e], with sporocarp size [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e] and nearest neighbour distance found to affect colonisation, abundance and diversity [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAlongside sporocarp size and nearest neighbour distance, other variables such as microclimate [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e], fungal species [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e] and degree of sporocarp decomposition [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e] have been explored as determinates of saproxylic species distribution and richness. Bracket microclimate, also thought an important determinant of saproxylic diversity, has been found to be affected by height above the ground [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Though brackets provide resources to invertebrates independent of their species (such as physical shelter), it has been demonstrated that phylogenetically and ecologically associated brackets on the same tree or log support different invertebrate communities [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e], indicating that there is a degree of specificity to interactions, which may be mediated by texture [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e] and endogenous biochemistry [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eWe used the fruiting bodies of \u003cem\u003eFomitopsis betulina\u003c/em\u003e, a common polypore of birch trees, to generate pilot data on which factors may contribute to arthropod diversity within this system. We found that arthropod abundance increases only with bracket size, and diversity and species richness decrease with increased fruiting body isolation.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003e\u003cem\u003ei. Sporocarp collection\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eEighteen sporocarps from fourteen woodpiles were collected from Ercall Wood, Shropshire, UK 2013/06/16 using random stratified sampling, ensuring collection of sporocarps of a range of sizes. Ercall Wood is a steep, mixed broad-leaf forest with a maximum elevation of 265m (Fig. 1).\u003c/p\u003e\n\u003cp\u003eTo avoid confounds from decomposition stage; only sporocarps that were over one year old and less than two years old (\u003cem\u003ei.e.\u003c/em\u003e sporocarps from the previous year\u0026rsquo;s growing season) were collected. The collected sporocarps correspond to between stages 2 and 3 in [12] and stage 3 in [13].\u003c/p\u003e\n\u003cp\u003eOn collection, the height of the sporocarp above the ground, measured as the distance between the soil surface and the lowest point of the sporocarp, was recorded to the nearest centimetre. The number of brackets present on the dead wood were also documented, as was the location of the next nearest \u003cem\u003eF. betulina \u003c/em\u003ebracket on a different log. Only fruiting bodies GPS coordinates were used to establish nearest neighbour distances. The haversine formula tool [14] provided a straight-line distance between two GPS coordinates to the nearest 1 cm. GPS coordinates were recorded using \u0026ldquo;GPS Location\u0026rdquo; application (cop-apps.net) installed on a Samsung SIII-mini smartphone. Brackets were collected by hand, wrapped in newspaper and stored in re-sealable plastic bags.\u003c/p\u003e\n\n\u003cp\u003e\u003cem\u003eii. Sporocarp volume\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eTo measure volume, each sporocarp was placed into a re-sealable plastic sandwich bag from which all the air was expelled. Depending on the size of the bracket, the sporocarp was submerged into a bucket, a 500 ml beaker or a glass tumbler. Each container was filled to the brim with water to ensure maximum displacement. The total volume displaced by the sporocarp was caught in a tray and then measured to the nearest 5ml.\u003c/p\u003e\n\n\u003cp\u003e\u003cem\u003eiii. Invertebrate identification\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eSporocarps were dissected using a scalpel under dissecting binocular microscope. Invertebrates were extracted using fine forceps and a paintbrush before being sacrificed in and stored in 80% ethanol before being sorted into morphospecies (Table S1).\u003c/p\u003e\n\u003cp\u003e\u003cimg src=\"data:image/png;base64,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\" width=\"190\" height=\"91\"\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eiv. Diversity\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eArthropod abundance, species richness and diversity were recorded from each individual bracket. Diversity was calculated using the Shannon-Wiener index (H\u0026rsquo;):\u003c/p\u003e\n\u003cp\u003eWhere \u003cem\u003ep\u003c/em\u003e\u003csub\u003ei\u003c/sub\u003e = the proportion of the total individuals belonging to the \u003cem\u003ei\u003c/em\u003eth species. Analysis was conducted on the effective number of species\u003cem\u003e \u003c/em\u003ebeing a more accurate measure of true diversity and permitting comparisons across diversity indices [15]:\u003c/p\u003e\n\u003cp\u003e\u003cimg src=\"data:image/png;base64,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\" width=\"436\" height=\"37\"\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003ev. Statistics\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eAll statistics were conducted using R v.4.4.0 [16]. Maximal models were initially fitted followed by step-wise elimination of non-significant terms to arrive at the minimum adequate model. Generalised linear models (GLM) and model simplification were all conducted using the R base package. Maximal models were fitted using the following explanatory variables with no interaction terms; log sporocarp volume; nearest sporocarp neighbour; number of other sporocarps at the same log pile; sporocarp height above the ground. Model term significance was assessed using an F-test implemented via the function \u0026lsquo;drop1\u0026rsquo;, non-significant model terms were eliminated until a minimum adequate model was obtained. Abundance and species richness were overdispersed count data and were therefore modelled using a quasipoisson distribution. Effective number of species presented non-normally distributed residuals and were therefore modelled using a gamma distribution.\u003c/p\u003e"},{"header":"Results and Discussion","content":"\u003cp\u003eWe found that sporocarp size was a significant predictor of arthropod abundance (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eA; GLM, F\u003csub\u003e1,18\u003c/sub\u003e = 5.29, p\u0026thinsp;=\u0026thinsp;0.035), larger sporocarps supported a greater number of individuals; in concordance with other investigations into saproxylic biodiversity [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Only nearest sporocarp neighbour was a significant predictor of species richness (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eB; GLM, F\u003csub\u003e1,18\u003c/sub\u003e = 7.70, p\u0026thinsp;=\u0026thinsp;0.014) and saproxylic diversity (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eC; GLM, F\u003csub\u003e1,18\u003c/sub\u003e = 7.70, p\u0026thinsp;=\u0026thinsp;0.014); both richness and diversity decreased with increasing distance to nearest neighbour [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. The height of the sporocarp above the soil and the number of sporocarps present on the same piece of dead wood had no significant effect on arthropod abundance, species richness or diversity (GLM, F\u003csub\u003e1,18\u003c/sub\u003e \u0026lt; 2.40, p\u0026thinsp;\u0026gt;\u0026thinsp;0.14).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThese results in part support the concept that bracket fungi sporocarps operate as biological islands; where species richness and diversity may decrease with increased distance to their nearest neighbour. Island biogeography theory also predicts that larger \u0026lsquo;islands\u0026rsquo; will support greater diversity, in line with general species-area affects; increased area (or volume, in this instance) predicted to support greater diversity by providing a wider range of ecological niches that can be exploited [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Different sized \u003cem\u003eF. betulinus\u003c/em\u003e sporocarps may provide varying niches; they can be heterogeneous in texture [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e], features that could be differentially exploited by specific mycophagous or visiting species. Distance from nearest neighbour may be less relevant to winged groups that can disperse distances greater than the study area, but some groups (\u003cem\u003ee.g.\u003c/em\u003e Carabidae) are not mycophagous and may be utilising sporocarps for hunting or for physical shelter.\u003c/p\u003e \u003cp\u003eOther studies found that height above the soil, an indicator of microclimate [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e], a factor not a significant variable in our analysis. We also did not find a relationship between sporocarp size and effective number of species (an indicator of diversity), contrasting with other investigations [\u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Our data may differ from previous results due to differences in focal fungal species and the size therein of the fruiting bodies or due to differences in saproxylic species (\u003cem\u003ee.g.\u003c/em\u003e size-diversity relationships may only for Coleoptera [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e"},{"header":"Limitations","content":"\u003cp\u003eThe most significant limitation to this work is the small number of \u003cem\u003eF. betulina\u003c/em\u003e fruiting bodies that were collected. To draw stronger conclusions regarding the data collected, a much greater sample size, preferably sampling over a wider geographic area would be needed. Additionally, sampling over a longer period would provide a better indication of the variability of saproxylic species utilising these sporocarps, as would rearing insects from the fruiting bodies rather than dissecting them. The lack of genus or species level identification, rather than morphospecies, is also a limitation on these results.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eNo applicable.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eEthics approval and consent to participate\u003c/p\u003e\n\u003cp\u003eThe animals sacrificed during this experiment are not subject to any legal or formal ethical oversight. However, care was taken during animal handling to minimise stress and avoid injury. Animal sacrifice was designed to be as rapid as possible while preserving specimens for identification.\u003c/p\u003e\n\u003cp\u003e· Consent for publication\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e· Availability of data and materials\u003c/p\u003e\n\u003cp\u003eThe datasets generated and/or analysed during the current study are available in the Open Science Foundation repository, doi.org/10.17605/osf.io/vewj8\u003c/p\u003e\n\u003cp\u003e· Competing interests\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e· Funding\u003c/p\u003e\n\u003cp\u003eResources were provided to CDP via Harper Adams University MSc Entomology course.\u003c/p\u003e\n\u003cp\u003e· Authors' contributions\u003c/p\u003e\n\u003cp\u003eCDP and SRL conceptualized the project and designed methodology. CDP conducted formal analysis, investigation, visualisation, writing of original draft, and editing. SRL was responsible for funding acquisition, project administration, providing resources, and supervision.\u003c/p\u003e\n\u003cp\u003e· Acknowledgements\u003c/p\u003e\n\u003cp\u003eWe would like to extend thanks to Roy Mantle of the Shropshire Mycological Society for advice on sampling site selection and to Glenda Orledge for sharing her knowledge of and enthusiasm for bracket fungi and saproxylic invertebrates. Thanks also to Meghan Barrett and an anonymous referee for insightful comments on this manuscript.\u003c/p\u003e\n\u003cp\u003e· Authors' information (optional)\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eKomonen A. Hotspots of Insect Diversity in Boreal Forests. Conservation Biology. 2003;17:976\u0026ndash;81.\u003c/li\u003e\n\u003cli\u003eKadowaki K. Wood-decaying Fungi and Beetles, a multilateral approach to studying fungus \u0026ndash;insect communities. University of Auckland; 2010.\u003c/li\u003e\n\u003cli\u003eItescu Y. Are island-like systems biologically similar to islands? A review of the evidence. Ecography. 2019;42:1298\u0026ndash;314.\u003c/li\u003e\n\u003cli\u003eO\u0026rsquo;Connell T, Bolger T. Fungal Fruiting Bodies and the Structure of Fungus-Micro-Arthropod Assemblages. Biology and Environment: Proceedings of the Royal Irish Academy. 1997;97B:249\u0026ndash;62.\u003c/li\u003e\n\u003cli\u003eThunes KH, Midtgaard F, Gjerde I. Diversity of Coleoptera of the bracket fungus \u003cem\u003eFomitopsis pinicola\u003c/em\u003e in a Norwegian spruce forest. Biodivers Conserv. 2000;9:833\u0026ndash;52.\u003c/li\u003e\n\u003cli\u003eSelonen VAO, Ahlroth P, Kotiaho JS. Anthropogenic disturbance and diversity of species: polypores and polypore-associated beetles in forest, forest edge and clear-cut. Scand J For Res. 2005;20:49\u0026ndash;58.\u003c/li\u003e\n\u003cli\u003eJonsell M, Nordlander G, Jonsson M. Colonization Patterns of Insects Breeding in Wood-Decaying Fungi. J Insect Conserv. 1999;3:145\u0026ndash;61.\u003c/li\u003e\n\u003cli\u003eKomonen A. Structure of insect communities inhabiting old-growth forest specialist bracket fungi. Ecol Entomol. 2001;26:63\u0026ndash;75.\u003c/li\u003e\n\u003cli\u003eGdula AK, Konwerski S, Olejniczak I, Rutkowski T, Skubała P, Zawieja B, et al. The role of bracket fungi in creating alpha diversity of invertebrates in the Białowieża National Park, Poland. Ecol Evol. 2021;11:6456\u0026ndash;70.\u003c/li\u003e\n\u003cli\u003eJonsell M, Nordlander G, Ehnstr\u0026ouml;m B. Substrate Associations of Insects Breeding in Fruiting Bodies of Wood-Decaying Fungi. Ecological Bulletins. 2001;:173\u0026ndash;94.\u003c/li\u003e\n\u003cli\u003ePaviour-Smith K. The Fruiting-Bodies of Macrofungi as Habitats for Beetles of the Family Ciidae (Coleoptera). Oikos. 1960;11:43\u0026ndash;71.\u003c/li\u003e\n\u003cli\u003eKrasutskii B V. Beetles (Coleoptera) associated with the birch fungus \u003cem\u003ePiptoporus betulinus\u003c/em\u003e (Bull.: Fr.) P. Karst. (Basidiomycetes, Aphyllophorales) in forests of the Urals and Transurals. Entomological Review 2006 86:8. 2006;86:889\u0026ndash;900.\u003c/li\u003e\n\u003cli\u003eGraves RC. Ecological Observations on the Insects and Other Inhabitants of Woody Shelf Fungi (Basidiomycetes: Polyporaceae) in the Chicago Area. Ann Entomol Soc Am. 1960;53:61\u0026ndash;78.\u003c/li\u003e\n\u003cli\u003eVeness C. Latitude/longitude spherical geodesy tools. 2012. www.movable-type.co.uk/scripts/latlong.html.\u003c/li\u003e\n\u003cli\u003eJost L. Entropy and diversity. Oikos. 2006;113:363\u0026ndash;75.\u003c/li\u003e\n\u003cli\u003eR Core Team. R: A Language and Environment for Statistical Computing. 2024.\u003c/li\u003e\n\u003cli\u003eMatthews TJ, Triantis K. Island biogeography. Current Biology. 2021;31:R1201\u0026ndash;R1207.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-research-notes","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"resn","sideBox":"Learn more about [BMC Research Notes](http://bmcresnotes.biomedcentral.com)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/resn/default.aspx","title":"BMC Research Notes","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Bracket fungi, polypore, saproxylic, biodiversity, forest, biological islands, sporocarp, insect, arthropod","lastPublishedDoi":"10.21203/rs.3.rs-6734571/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6734571/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjective: \u003c/strong\u003eCertain basidiomycete fungi produce semi-stable fruiting bodies, known as brackets, that support a significant quality of saproxylic invertebrate biodiversity, especially in northern forests. The objective of this investigation was to assess the drivers of saproxylic diversity within the fruiting bodies of \u003cem\u003eFomitopsis betulina.\u003c/em\u003eWe explore which factors are significant determinants of arthropod diversity and abundance, examining the effects of sporocarp size, height above the ground, and relative isolation from neighbouring sporocarps.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eWe find that larger sporocarps support a greater number of saproxylic arthropods, but diversity and species richness are determined by distance from nearest neighbour.\u003c/p\u003e","manuscriptTitle":"Factors determining diversity of saproxylic arthropods in the fruiting bodies of the birch polypore fungus (Fomitopsis betulina)","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-26 13:35:30","doi":"10.21203/rs.3.rs-6734571/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-07-14T10:10:59+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-12T06:45:02+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-04T13:46:27+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"63537571583825997815072386451425285691","date":"2025-07-03T20:17:18+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-03T08:47:48+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-02T13:11:39+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-02T12:54:04+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"17166690799851552203008392813814262647","date":"2025-07-02T12:04:32+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"310042285880683916802206348809633109705","date":"2025-07-02T04:16:29+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"109524651219792320152221570169497068013","date":"2025-06-26T13:19:58+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"113815465184811241453644815444091868447","date":"2025-06-26T11:58:17+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"108247043990408539214017323730812273849","date":"2025-06-25T07:23:38+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"43638602016766555295422542243125843679","date":"2025-06-24T14:59:45+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-06-24T11:40:52+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-05-28T09:27:45+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-05-28T09:17:55+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-05-28T09:14:47+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Research Notes","date":"2025-05-23T16:24:12+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-research-notes","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"resn","sideBox":"Learn more about [BMC Research Notes](http://bmcresnotes.biomedcentral.com)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/resn/default.aspx","title":"BMC Research Notes","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"880eb0ab-fc42-44c4-8fbb-06344d7b1b20","owner":[],"postedDate":"June 26th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-08-25T16:38:11+00:00","versionOfRecord":{"articleIdentity":"rs-6734571","link":"https://doi.org/10.1186/s13104-025-07434-6","journal":{"identity":"bmc-research-notes","isVorOnly":false,"title":"BMC Research Notes"},"publishedOn":"2025-08-18 16:29:45","publishedOnDateReadable":"August 18th, 2025"},"versionCreatedAt":"2025-06-26 13:35:30","video":"","vorDoi":"10.1186/s13104-025-07434-6","vorDoiUrl":"https://doi.org/10.1186/s13104-025-07434-6","workflowStages":[]},"version":"v1","identity":"rs-6734571","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6734571","identity":"rs-6734571","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}