{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,19]],"date-time":"2026-10-19T22:08:38Z","timestamp":1792447718408,"version":"4.5.0"},"reference-count":37,"publisher":"The Royal Society","issue":"2080","license":[{"start":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T00:00:00Z","timestamp":1791936000000},"content-version":"vor","delay-in-days":7,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000001","name":"National Science Foundation","doi-asserted-by":"publisher","award":["NSF-DBI-2329961"],"award-info":[{"award-number":["NSF-DBI-2329961"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,10,7]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Host and parasite body size frequently scale positively (often referred to as Harrison\u2019s rule), potentially as a result of fundamental constraints on large parasite species simply being morphologically incapable of infecting small host species, or through a variety of alternative proposed mechanisms. Regardless of mechanism, Harrison\u2019s rule does have some empirical support. Here, we leverage several trait databases and a large set of host\u2013helminth parasite interactions to gauge support for Harrison\u2019s rule in parasitic helminths. We fit generalized additive models from both the host perspective (do larger host species tend to have larger average parasites?) and the parasite perspective (do larger parasite species tend to infect larger average host species?) across a range of host taxa including mammals, birds and fish. We find support for both relationships in mammals, moderate support in fish and very limited support in birds, relative to a null model. Together, we demonstrate positive host\u2013parasite body size scaling in parasitic helminths, suggesting the potential for fundamental morphological constraints on host\u2013parasite interactions, while also highlighting the clear differences in body size scaling across host taxa.<\/jats:p>","DOI":"10.1098\/rspb.2026.1330","type":"journal-article","created":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T00:22:16Z","timestamp":1791937336000},"source":"Crossref","is-referenced-by-count":1,"title":["Helminth parasite body size scaling with host species size"],"prefix":"10.1098","volume":"293","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3328-9958","authenticated-orcid":false,"given":"Tad","family":"Dallas","sequence":"first","affiliation":[{"name":"Department of Biological Sciences, University of South Carolina System 1 , Columbia, SC, 29208, USA"},{"name":"Center for the Ecology of Infectious Diseases, University of Georgia 2 , Athens, GA, 30602, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lauren A.","family":"Holian","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, University of South Carolina System 1 , Columbia, SC, 29208, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1167-4425","authenticated-orcid":false,"given":"Grant","family":"Foster","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, University of South Carolina System 1 , Columbia, SC, 29208, USA"},{"name":"Department of Biology, Texas Wesleyan University 3 , Fort Worth, TX 76105, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"175","published-online":{"date-parts":[[2026,10,14]]},"reference":[{"key":"2026101906135206900_RSPB02261330C1","doi-asserted-by":"crossref","first-page":"763","DOI":"10.1017\/S0031182006002150","article-title":"Are there general laws in parasite ecology?","volume":"134","author":"Poulin","year":"2007","journal-title":"Parasitology"},{"key":"2026101906135206900_RSPB02261330C2","doi-asserted-by":"crossref","first-page":"1159","DOI":"10.1111\/ele.12644","article-title":"The macroecology of infectious diseases: a new perspective on global-scale drivers of pathogen distributions and impacts","volume":"19","author":"Stephens","year":"2016","journal-title":"Ecol. Lett."},{"key":"2026101906135206900_RSPB02261330C3","doi-asserted-by":"crossref","first-page":"1437","DOI":"10.1111\/geb.12819","article-title":"Gauging support for macroecological patterns in helminth parasites","volume":"27","author":"Dallas","year":"2018","journal-title":"Glob. Ecol. Biogeogr."},{"key":"2026101906135206900_RSPB02261330C4","doi-asserted-by":"crossref","first-page":"804","DOI":"10.1111\/geb.12894","article-title":"Contrasting latitudinal gradients of body size in helminth parasites and their hosts","volume":"28","author":"Dallas","year":"2019","journal-title":"Glob. Ecol. Biogeogr."},{"key":"2026101906135206900_RSPB02261330C5","doi-asserted-by":"crossref","first-page":"20200361","DOI":"10.1098\/rstb.2020.0361","article-title":"Spatial variation in species roles in host--helminth networks","volume":"376","author":"Dallas","year":"2021","journal-title":"Phil. Trans. R. Soc. 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