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Aim: Climate change influences species distribution in space and time, but predicting the overlap in the range of interacting species under different climate scenarios remains a challenge. Here, we explore how climate change influences shifts in species ranges among mutualists. Location: Cape Floristic Region (CFR), South Africa. Taxon: Proteaceae and Passeriformes. Methods: We used machine‐learning algorithms (random forest and boosted‐regression trees) and regression model (generalized additive models) to predict range shifts of 11 bird‐pollinated Proteaceae species, combined occurrence prediction of 71 bird‐pollinated Proteaceae and their two most important, endemic, pollinator bird species. We determined the degree of overlap in geographical ranges of nectar‐feeding birds and Proteaceae under different climate scenarios. Species ranges were projected to the years 2050 and 2070 using representative concentration pathways (RCP) 4.5 and 8.5 and three global climate models. Results: The majority of Proteaceae species in our model are predicted to experience range contractions, which ranged from 1% under 2050 RCP 4.5 CCSM4 to 79% under 2070 RCP 8.5 CNRM‐CM5 climate scenarios, leading to 55% and 62% range loss for Cape sugarbird and orange‐breasted sunbird, respectively, under extreme climate scenarios. Proteaceae species are predicted to experience least overlap with nectar‐feeding birds in the northern and eastern range under future climate scenarios. Main Conclusion: Climate change threatens species occupying the mountain range of the northern limit and other regions of the CFR. Reduced range overlap of mutualists may have significant implications for the reproduction and persistence of Proteaceae. We suggest active monitoring of Proteaceae populations in regions where species are predicted to lose their range, particularly so for threatened species with small ranges. [ABSTRACT FROM AUTHOR]

Aim Wallacea, the vast oceanic boundary between the Oriental and Australian regions, contains 122 true nectarivorous bird species. It is the contact zone of the Oriental sunbirds and the Australian honeyeaters, and at least three more true nectarivorous families are resident in the region. An island–bird matrix for Wallacea was tested for the presence of two patterns, nestedness and modularity. If the matrix is modular, it consists of a number of densely linked subgroups or modules of islands and birds, which are weakly interconnected. These modules are used as a new tool in analysing biogeographical boundaries in Wallacea. Location Wallacea, Indonesia. Methods We constructed an island–bird matrix for Wallacea and used two algorithms,aninhado andsa, to test it for nestedness and modularity, respectively.aninhado calculates the matrix temperature and provides a null model, andsa is a module-detecting program based on simulated annealing. The results of thesa were compared with those from a hierarchical cluster analysis. Results The matrix had a nested pattern, as is commonly the case for island–species matrices. The SA detected four modules in Wallacea, each consisting of a group of islands sharing a group of nectarivorous birds. Thesa algorithm produced a more detailed pattern of the area than did the hierarchical cluster analysis. Main conclusions Modularity and nestedness do not preclude each other as biogeographical patterns. The boundaries of the modules detected bysa compared well with major boundaries from the existing literature and showed a clear division of Wallacea into modules of birds and islands closely linked together. Thus modules are biogeographical units of islands sharing a specific nectarivorous fauna. For some research questions, we suggest that modules may be more appropriate biogeographical units than single islands or traditionally perceived archipelagos. The nectarivorous families showed distinctly different distributions, indicating variation in their colonization history and speciation processes. We recommendsa as a tool for detecting fine-grained biogeographical patterns. [ABSTRACT FROM AUTHOR]