LB 30-292 - Impacts of lemur extinction: the loss of large-bodied generalist threatens plant communities

Background/Question/Methods:

Interactions between plants and animals, such as plant-seed disperser mutualisms, are essential for the functioning of ecosystems. Such interactions are unfortunately at risk, as animal partners face extinction. Using a dataset encompassing plant-lemur interactions across Madagascar, we examined first the structure of these interactions and then how they may change when lemur species are lost. We investigated how the extinction of critically endangered lemurs can alter this structure, impacting the survival of the plants that depend on them. We also assessed the robustness of the interaction network to the loss of lemur species of varying endangered status, degree of specialization, and body size. We found a structure indicative of coevolution, highlighting the importance of evolutionary history and the risks associated with losing co-evolved partners.

Results/Conclusions:

We found that losing critically endangered species left 164 plant species without frugivore partners. This increased the nestedness of the network and rearranged the composition of its modules. However, the robustness of the interaction network was not sensitive to the loss of critically endangered species. Instead, the network was least robust to the loss of large-bodied and generalists lemurs. These results suggest the importance of the structure of plant-animal interactions for informing conservation priorities.