Global and regional ecological boundaries explain abrupt spatial discontinuities in avian frugivory interactions

Species interactions can propagate disturbances across space via direct and indirect effects, potentially connecting species at a global scale. However, ecological and biogeographic boundaries may mitigate this spread by demarcating the limits of ecological networks. We tested whether large-scale ecological boundaries (ecoregions and biomes) and human disturbance gradients increase dissimilarity among plant-frugivore networks, while accounting for background spatial and elevational gradients and differences in network sampling. We assessed network dissimilarity patterns over a broad spatial scale, using 196 quantitative avian frugivory networks (encompassing 1496 plant and 1004 bird species) distributed across 67 ecoregions, 11 biomes, and 6 continents. We show that dissimilarities in species and interaction composition, but not network structure, are greater across ecoregion and biome boundaries and along different levels of human disturbance. Our findings indicate that biogeographic boundaries delineate the world’s biodiversity of interactions and likely contribute to mitigating the propagation of disturbances at large spatial scales.The authors acknowledge the following funding: University of Canterbury Doctoral Scholarship (L.P.M.); The Marsden Fund grant UOC1705 (J.M.T., L.P.M.); The São Paulo Research Foundation - FAPESP 2014/01986-0 (M.G., C.E.), 2015/15172-7 and 2016/18355-8 (C.E.), 2004/00810-3 and 2008/10154-7 (C.I.D., M.G., M.A.P.); Earthwatch Institute and Conservation International for financial support (C.I.D., M.G., M.A.P.); Carlos Chagas Filho Foundation for Supporting Research in the Rio de Janeiro State – FAPERJ grant E-26/200.610/2022 (C.E.); Brazilian Research Council grants 540481/01-7 and 304742/2019-8 (M.A.P.) and 300970/2015-3 (M.G.); Rufford Small Grants for Nature Conservation No. 22426–1 (J.C.M., I.M.), No. 9163-1 (G.B.J.) and No. 11042-1 (MCM); Universidade Estadual de Santa Cruz (Propp-UESC; No. 00220.1100.1644/10-2018) (J.C.M., I.M.); Fundação de Amparo à Pesquisa do Estado da Bahia - FAPESB (No. 0525/2016) (J.C.M., I.M.); European Research Council under the European Union’s Horizon 2020 research and innovation program (grant 787638) and The Swiss National Science Foundation (grant 173342), both awarded to C. Graham (D.M.D.); ARC SRIEAS grant SR200100005 Securing Antarctica’s Environmental Future (D.M.D.); German Science Foundation—Deutsche Forschungsgemeinschaft PAK 825/1 and FOR 2730 (K.B.G., E.L.N., M.Q., V.S., M.S.), FOR 1246 (K.B.G., M.S., M.G.R.V.) and HE2041/20-1 (F.S., M.S.); Portuguese Foundation for Science and Technology - FCT/MCTES contract CEECIND/00135/2017 and grant UID/BIA/04004/2020 (S.T.) and contract CEECIND/02064/2017 (L.P.S.); National Scientific and Technical Research Council, PIP 592 (P.G.B.); Instituto Venezolano de Investigaciones Científicas - Project 898 (V.S.D.)

Data and code: Global and regional ecological boundaries explain abrupt spatial discontinuities in avian frugivory interactions

Zip-file including the Data and Code necessary for reproducing the analyses from 'Global and regional ecological boundaries explain abrupt spatial discontinuities in avian frugivory interactions'. General Information regarding the data is included as a pdf file in the download.Species interactions can propagate disturbances across space via direct and indirect effects, potentially connecting species at a global scale. However, ecological and biogeographic boundaries may mitigate this spread by demarcating the limits of ecological networks. We tested whether large-scale ecological boundaries (ecoregions and biomes) and human disturbance gradients increase dissimilarity among plant-frugivore networks, while accounting for background spatial and elevational gradients and differences in network sampling. We assessed network dissimilarity patterns over a broad spatial scale, using 196 quantitative avian frugivory networks (encompassing 1,496 plant and 1,004 bird species) distributed across 67 ecoregions, 11 biomes, and 6 continents. We show that dissimilarities in species and interaction composition, but not network structure, are greater across ecoregion and biome boundaries and along different levels of human disturbance. Our findings indicate that biogeographic boundaries delineate the world’s biodiversity of interactions and likely contribute to mitigating the propagation of disturbances at large spatial scales.Funding: University of Canterbury Doctoral Scholarship; The Marsden Fund, Award: UOC1705; Earthwatch Institute and Conservation International for financial support; Carlos Chagas Filho Foundation for Supporting Research in the Rio de Janeiro State – FAPERJ , Award: E-26/200.610/2022 Universidade Estadual de Santa Cruz, Award: Propp-UESC No. 00220.1100.1644/10-2018; Fundação de Amparo à Pesquisa do Estado da Bahia, Award: 0525/2016; Horizon 2020, Award: 787638; Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, Award: 173342 ARC SRIEAS, Award: SR200100005; National Scientific and Technical Research Council, Award: PIP 592; Instituto Venezolano de Investigaciones Científicas, Award: Project 898; Fundação de Amparo à Pesquisa do Estado de São Paulo, Award: 2014/01986-0; Fundação de Amparo à Pesquisa do Estado de São Paulo, Award: 2015/15172-7; Fundação de Amparo à Pesquisa do Estado de São Paulo, Award: 2016/18355-8; Fundação de Amparo à Pesquisa do Estado de São Paulo, Award: 2004/00810-3; Fundação de Amparo à Pesquisa do Estado de São Paulo, Award: 2008/10154-7; Brazilian Research Council, Award: 540481/01-7; Brazilian Research Council, Award: 304742/2019-8; Brazilian Research Council, Award: 300970/2015-3; Rufford Small Grants for Nature Conservation, Award: 22426–1; Rufford Small Grants for Nature Conservation, Award: 9163-1; Rufford Small Grants for Nature Conservation, Award: 11042-1; Deutsche Forschungsgemeinschaft, Award: PAK 825/1; Deutsche Forschungsgemeinschaft, Award: FOR 2730 Deutsche Forschungsgemeinschaft, Award: FOR 1246; Deutsche Forschungsgemeinschaft, Award: HE2041/20-1; Fundação para a Ciência e a Tecnologia, Award: CEECIND/00135/2017; Fundação para a Ciência e a Tecnologia, Award: UID/BIA/04004/2020; Fundação para a Ciência e a Tecnologia, Award: CEECIND/02064/2017Peer reviewe