biostudies-literatureUnknown31(12)Lu MMax Planck-Yale Center for Biodiversity and Global ChangeE.O. Wilson Biodiversity FoundationSichuan UniversityQuantifying the impacts of ongoing climate change on biodiversity is one of the most pressing scientific challenges. Recent studies have indicated the risk of widespread range contraction and community collapse globally, but their specific interpretation and decision relevance are constrained by the coarse-grain nature of their underlying evidence. Here, using a novel climate change vulnerability metric, we demonstrate for 1804 Western Hemisphere bird species that coarse-grain estimates of climate change vulnerability show limited correspondence with those derived from biologically more relevant fine-grain data. Coarse-grain data used widely in recent assessments miss up to half of the most vulnerable species due to various degrees of underestimation and overestimation that covary with spaGlobal change biologye70627https://www.ebi.ac.uk/biostudies/studies/S-EPMC12687110biostudies-literatureFine-Grain Data Reveal Vulnerability of Biodiversity to Climate Change.PMC12687110Lu MJetz WfalseFine-Grain Data Reveal Vulnerability of Biodiversity to Climate Change.Quantifying the impacts of ongoing climate change on biodiversity is one of the most pressing scientific challenges. Recent studies have indicated the risk of widespread range contraction and community collapse globally, but their specific interpretation and decision relevance are constrained by the coarse-grain nature of their underlying evidence. Here, using a novel climate change vulnerability metric, we demonstrate for 1804 Western Hemisphere bird species that coarse-grain estimates of climate change vulnerability show limited correspondence with those derived from biologically more relevant fine-grain data. Coarse-grain data used widely in recent assessments miss up to half of the most vulnerable species due to various degrees of underestimation and overestimation that covary with spa2025-01-01T00:00:00Z2025 Dec2026-06-05T23:43:35.607Z2026-05-23T03:13:39.073ZS-EPMC126871104136303410.1111/gcb.70627