Local people enhance our understanding of Afrotropical frugivory networks

Afrotropical forests are undergoing massive change caused by defaunation, i.e., the human-induced decline of animal species,¹ most of which are frugivorous species.^1,2,3 Frugivores' depletion and their functional disappearance are expected to cascade on tree dispersal and forest structure via interaction networks,^4,5,6,7 as the majority of tree species depend on frugivores for their dispersal.⁸ However, frugivory networks remain largely unknown, especially in Afrotropical areas,^9,10,11 which considerably limits our ability to predict changes in forest dynamics and structures using network analysis.^12,13,14,15 While the academic workforce may be inadequate to fill this knowledge gap before it is too late, local ecological knowledge appears as a valuable source of ecological information and could significantly contribute to our understanding of such crucial interactions for tropical forests.^{16,17,18,19,20,21} To investigate potential synergies between local ecological knowledge and academic knowledge,^20,21 we compiled frugivory interactions linking 286 trees to 100 frugivore species from the academic literature and local ecological knowledge coming from interviews of Gabonese forest-dependent people. Here, we showed that local ecological knowledge on frugivory interactions was substantial and original, with 39% of these interactions unknown by science. We demonstrated that combining academic and local ecological knowledge affects the functional relationship linking frugivore body mass to seed size, as well as the network structure. Our results highlight the benefits of bridging knowledge systems between academics and local communities for a better understanding of the functioning and response to perturbations of Afrotropical forests.