Ecology, Evolution, Behavior and Systematics, Ecology, Global and Planetary Change, Nature and Landscape Conservation
6
Scopus Publications
Scopus Publications
Climate Change Will Resize and Reshape Plant–Hummingbird Networks in the Atlantic Forest Alejandro Restrepo‐González, Thais B. Zanata, Fernanda T. Brum, Silvana Buzato, Catherine H. Graham, Joice Iamara‐Nogueira, Isabela G. Varassin Diversity and Distributions, 2026 Aim To assess how climate change could reshape plant–hummingbird interaction networks in the Atlantic Forest by predicting shifts in species co‐occurrence and evaluating changes in network structure. Location Atlantic Forest, South America. Methods We used ecological niche modelling to predict changes in the co‐occurrence of plants and hummingbirds under climate change scenarios. Modelled networks were analysed to compare network metrics, such as network size, number of links, niche overlap and robustness, between present and future conditions. We also simulated species extinctions to assess network resilience. Results Future local networks showed lower species richness, reduced size, fewer links and shared partners, increased niche overlap and decreased robustness. While network robustness improved under simulated plant and secondary hummingbird extinctions, future networks exhibited reduced resilience to species loss. Plants had higher niche overlap than hummingbirds, making them more vulnerable to secondary extinctions driven by hummingbird losses. Main Conclusions Climate change is expected to drive shifts in species co‐occurrence, leading to novel assemblages and structural changes in plant–hummingbird interaction networks. These alterations will likely decrease network robustness and resilience, highlighting potential cascading effects on ecosystem function. Our findings contribute to understanding the impacts of climate change on mutualistic networks and ecosystem stability in the Atlantic Forest and beyond.
Mechanisms influencing network topology in plant–hummingbird pollination networks Ricardo Sánchez-Martín, Elisa Barreto, Melina F. Maxwell, Francois Duchenne, Holger Beck, Rafaela Bobato, Emanuel Brenes, Daniela Bôlla, Nicole Büttner, Ana Paula Caron, Alejandro Castro Jiménez, Nelson Chaves-Elizondo, María José Gavilanes, Anna Sofia Görlich, Esteban A. Guevara, Miriam Kaehler, Tiago Machado de Souza, Miguel Machnicki-Reis, Andrés Sebastián Marcayata-Fajardo, Cauã Galeazzi de Menezes, Andrea Nieto, Rafael Oliveira, Ricardo Augusto Camargo de Oliveira, Alejandro Restrepo-González, Friederike Richter, Bryan Gastón Rojas, Luciele Leonhardt Romanowski, Romulo Silva Cícero Silva, Wellinton Luiz de Souza, Francisco Tobar, Danila Syriani Veluza, Rafael O. Wüest, Thais Bastos Zanata, Krystal Zuniga, Tatiana Santander, María A. Maglianesi, Isabela G. Varassin, Catherine H. Graham Proceedings of the Royal Society B Biological Sciences, 2025 Ecological communities result from complex species interactions, often summarized in interaction networks. The structure of these networks is described by metrics that provide insight into community assembly, ecosystem functioning and coevolutionary processes. Despite advances in measuring and mapping network structure, the mechanisms underlying its formation remain less explored. Network metrics may vary across communities owing to changes in species diversity and environmental conditions. However, network metrics may remain invariant if mechanisms influencing interactions (linkage rules) are independent of species composition and environmental conditions and instead influenced by traits. We investigated whether changes in taxonomic, phylogenetic and functional diversity along elevation gradients influence network modularity, nestedness, connectance and specialization across 32 sites in Brazil, Costa Rica and Ecuador. Despite elevation’s impact on diversity, we found that it had no effect on network structure, which remained consistent across elevations. Instead, trait-based mechanisms, specifically the matching between hummingbird bills and flower corollas, emerged as a consistent driver of network structure. Species showing strong trait matching contributed more to modularity and specialization, but less to nestedness and connectance than expected by chance. These results suggest that trait matching influences the invariant structure of plant–hummingbird networks, persisting despite shifts in diversity across biogeographical regions and elevational gradients.
Hummingbird flower visitation rates vary with species traits, floral abundance and phenology across bioregions Elisa Barreto, François Duchenne, Holger Beck, Carolina Bello, Rafaela Bobato, Emanuel Brenes, Daniela Bôlla, Nicole Büttner, Ana Paula Caron, José Alejandro Castro, Nelson Chaves‐Elizondo, María José Gavilanes, Esteban A. Guevara, Miriam Kaehler, Tiago Machado‐de‐Souza, Miguel Machnicki-Reis, Andrés S. Marcayata‐Fajardo, Cauã G. de Menezes, Andrea Nieto, Rafael de Oliveira, Ricardo A. C. de Oliveira, Alejandro Restrepo-González, Friederike Richter, Bryan G. Rojas, Luciele L. Romanowski, Ricardo Sánchez-Martín, Romulo C. da Silva, Wellinton Luiz de Souza, Danila S. Veluza, Ben Weinstein, Rafael Wüest, Thais B. Zanata, Krystal Zuniga, Tatiana Santander, Maria A. Maglianesi, Isabela G. Varassin, Catherine H. Graham Oikos, 2025 A myriad of factors influence species interactions, and determining their relative importance is a major challenge in community ecology. Here, we explored the multiple factors influencing hummingbird visitation rates to flowers by considering pollinator and floral traits alongside the broader ecological context (i.e. phenology and floral abundance). Our data were collected from 32 systematically surveyed sites within native vegetation across three distinct Neotropical bioregions, each characterized by unique species composition and evolutionary histories. In total, we sampled 6423 flowering individuals, representing 404 plant species and 68 hummingbird species. At the community level, we found that hummingbirds primarily visit flowers with long, tubular corollas, aligning with predictions from pollination syndromes, and that visitation is also higher to flowers with straight corollas. At the species level, visitation frequency was associated with specific characteristics of the hummingbird species, such as its bill length and foraging behavior, where species often forage on flowers with matching morphological traits. Further, our findings extended beyond the expected trait preferences, revealing that visitation rates are also the outcome of the ecological context; particularly, the abundance of conspecific, but not heterospecific, flowers. The effect of conspecific abundance varied across bioregions, suggesting that from the plant perspective, intraspecific competition and facilitation could prevail in different regions. Additionally, we found that plant species whose floral morphology was more distinct from the other co‐flowering species tended to attract more visits, but only if they were abundant enough to stand out within the floral community. These findings highlight how plant and pollinator traits, modulated by the ecological context, jointly shape pollination dynamics.
A Probabilistic View of Forbidden Links: Their Prevalence and Their Consequences for the Robustness of Plant–Hummingbird Communities François Duchenne, Elisa Barreto, Esteban A. Guevara, Holger Beck, Carolina Bello, Rafaela Bobato, Daniela Bôlla, Emanuel Brenes, Nicole Büttner, Ana P. Caron, Nelson Chaves‐Elizondo, María J. Gavilanes, Alejandro Restrepo‐González, Jose Alejandro Castro, Miriam Kaehler, Tiago Machado‐de‐Souza, Miguel Machnicki‐Reis, Andrés Sebastián F. Marcayata, Cauã G. de Menezes, Andrea Nieto, Rafael de Oliveira, Ricardo A. C. de Oliveira, Friederike Richter, Bryan G. Rojas, Luciele L. Romanowski, Wellinton L. de Souza, Danila S. Veluza, Ben Weinstein, Rafael O. Wüest, Thais B. Zanata, Krystal Zuniga, María A. Maglianesi, Tatiana Santander, Isabela G. Varassin, Catherine H. Graham Ecology Letters, 2025 The presence in ecological communities of unfeasible species interactions, termed forbidden links, due to physiological or morphological exploitation barriers has been long debated, but little direct evidence has been found. Forbidden links are likely to make ecological communities less robust to species extinctions, stressing the need to assess their prevalence. Here, we used a dataset of plant–hummingbird interactions, coupled with a Bayesian hierarchical model, to assess the importance of exploitation barriers in determining species interactions. We found evidence for exploitation barriers between flowers and hummingbirds across the 32 studied communities; however, the proportion of forbidden links changed drastically among communities because of changes in trait distributions. The higher the proportion of forbidden links, the more they decreased network robustness because of constraints on interaction rewiring. Our results suggest that exploitation barriers are not rare in plant–hummingbird communities and have the potential to limit the rescue of species experiencing partner extinction.
Urban environments increase generalization of hummingbird-plant networks across climate gradients Pietro Kiyoshi Maruyama, Camila Bosenbecker, João Custódio F. Cardoso, Jesper Sonne, Caio S. Ballarin, Camila S. Souza, Johana Leguizamón, Ariadna Valentina Lopes, María A. Maglianesi, Mauricio Fernández Otárola, Juan L. Parra, João Carlos Pena, Mónica B. Ramírez-Burbano, Claudia I. Rodríguez-Flores, André R. Rech, Thais B. Zanata, Juan Fernando Acevedo-Quintero, Gabriela Almeida, Pedro Amaral Anselmo, Felipe W. Amorim, Sergio Montoya-Arango, Andréa Cardoso Araujo, Francielle Paulina de Araújo, María del Coro Arizmendi, Lucilene Brito, Alejandra Castillo-García, Amanda Graciela Cherutte, Carolina Figuerêdo Costa, Fernando Henrique Santos Ferreira, Manoel Martins Dias Filho, Angélica Vilas Boas da Frota, Alice Scheer Iepsen, Leandro Freitas, Ingrid Gabriela de Almeida, Ana Caroline Silva Gomes, Leandro Hachuy-Filho, Carlos Lara, Liliana Rosero Lasprilla, Julian Llano, Vivian Nakamura, Edvaldo Nunes Neto, Cristiane Estrêla C. Nunes, Caio Graco Machado, Monique Maianne, Oscar Marin-Gomez, Ubaldo Márquez-Luna, Ruara Soares Mendes, Juan Guillermo Mesa, Rafael Oliveira, Jeane Lima-Passos, Janayna Andreza S. Pereira, Alejandro Restrepo-González, Sarah Mendonça Rigotto, Bruno Magro Rodrigues, Ana Maria Rui, Diana Betancur Ruiz, Luis Sandoval, Carina Araujo Santana, Jéssica Luiza S. Silva, Larissa Lais Silva, Vinicius Calda Santos, Paulo Antonio Silva, Maria Cristina Vargas-Espinosa, Breno Dias Vitorino, Marina Wolowski, Ivan Sazima, Marlies Sazima, Bo Dalsgaard, Jeferson Vizentin-Bugoni, Paulo E. Oliveira Proceedings of the National Academy of Sciences of the United States of America, 2024 Urbanization has reshaped the distribution of biodiversity on Earth, but we are only beginning to understand its effects on ecological communities. While urbanization may have homogenization effects strong enough to blur the large-scale patterns in interaction networks, urban community patterns may still be associated with climate gradients reflecting large-scale biogeographical processes. Using 103 hummingbird–plant mutualistic networks across continental Americas, including 176 hummingbird and 1,180 plant species, we asked how urbanization affects species interactions over large climate gradients. Urban networks were more generalized, exhibiting greater interaction overlap. Higher generalization was also associated with lower precipitation in both urban and natural areas, indicating that climate affects networks irrespective of habitat type. Urban habitats also showed lower hummingbird functional trait diversity and over/underrepresentation of specific clades. From the plant side, urban communities had a higher prevalence of nonnative nectar plants, which were more frequently visited by the hummingbird species occurring in both urban and natural areas. Therefore, urbanization affected hummingbird–plant interactions through both the composition of species and traits, as well as floral resource availability. Taken together, we show that urbanization consistently modifies ecological communities and their interactions, but climate still plays a role in affecting the structure of these novel communities over the scale of continents.
