The study by Olesen et al. examines the modularity of pollination networks, which are complex ecological networks formed by interactions between plant species and their pollinators. Modularity refers to the organization of these networks into distinct, interlinked subsets of species (modules) that are internally strongly connected. The authors used a simulated annealing algorithm to analyze 51 pollination networks, including nearly 10,000 species and 20,000 links. They found that networks with more than 150 species were modular, while those with fewer than 50 species were not. The number and size of modules increased with the number of species. Each module typically includes one or a few species groups with convergent traits, suggesting coevolutionary units. Species played different roles, with only 15% being structurally important to their network, either as hubs (highly linked within their module), connectors (linking different modules), or both. The study highlights the importance of identifying and conserving these key species to maintain network stability and prevent cascading extinctions. The findings also suggest that modularity and nestedness are complementary properties of pollination networks, providing insights into the structure and function of these complex ecological systems.The study by Olesen et al. examines the modularity of pollination networks, which are complex ecological networks formed by interactions between plant species and their pollinators. Modularity refers to the organization of these networks into distinct, interlinked subsets of species (modules) that are internally strongly connected. The authors used a simulated annealing algorithm to analyze 51 pollination networks, including nearly 10,000 species and 20,000 links. They found that networks with more than 150 species were modular, while those with fewer than 50 species were not. The number and size of modules increased with the number of species. Each module typically includes one or a few species groups with convergent traits, suggesting coevolutionary units. Species played different roles, with only 15% being structurally important to their network, either as hubs (highly linked within their module), connectors (linking different modules), or both. The study highlights the importance of identifying and conserving these key species to maintain network stability and prevent cascading extinctions. The findings also suggest that modularity and nestedness are complementary properties of pollination networks, providing insights into the structure and function of these complex ecological systems.