Browsing by Autor "Christine E. Edwards"

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Expelled by the Antarctic ice: Evolutionary history of the tribe Cunonieae (Cunoniaceae)
(Wiley, 2025) Francisco Fajardo‐Gutiérrez; Mariasole Calbi; Markus S. Dillenberger; J. Sebastián Tello; A C.; Nora H. Oleas; Ricardo A. Segovia; Christine E. Edwards; Yohan Pillon; James Richardson
Abstract The tribe Cunonieae comprises five genera and 214 species of shrubs and trees currently distributed in the Southern Hemisphere and the tropics, exhibiting an amphi‐Pacific disjunct distribution shared with Araucariaceae, Myrtaceae, Nothofagaceae, Podocarpaceae, and Proteaceae, among others. To address the central question of how historical geological forces have shaped the distribution of plant diversity in the southern hemisphere, we aimed to provide evidence from the biogeographical history of Cunonieae. We generated the most densely sampled phylogenetic trees of Cunonieae available to date, with 121 samples and 81 species, based on 404 new sequences of plastid and nuclear DNA regions with high hierarchical phylogenetic signal ( matK , trnL‐F , rpl16 , and internal transcribed spacer (ITS)). We included 184 samples of Rosids to estimate divergence times using fossil calibration points. For biogeographic inference, we employed a time‐stratified model including fossils as tips. Cunonia and Pterophylla were paraphyletic in the ITS tree, and Cunonia was paraphyletic in the plastid tree. Pancheria , Vesselowskya , and Weinmannia were monophyletic, the latter with conflicting nuclear and plastid phylogenies. The crown group Cunonieae was dated at ~56 Ma, and its ancestral areas were Antarctica and Patagonia. Antarctica acted as a bridge between Australia and South America before the consolidation of the Antarctic Ice Sheet and the extinction of the lineage in Antarctica from the Oligocene to the Miocene. Following that, Cunonieae spread to lower latitudes via Zealandia/Oceania and Patagonia/South America. Geological changes during the Pliocene facilitated a further burst in diversification along the Andes, in Madagascar, and in New Caledonia, where at least three colonization events occurred.
Functional traits mediate the effect of environmental conditions on tree growth of common Andean trees
(Elsevier BV, 2025) Eduardo Aguirre-Mazzi; Carla Maldonado; Leslie Cayola; Alfredo F. Fuentes; M. Isabel Loza; Christine E. Edwards; J. Sebastián Tello
Understanding how plant functional strategies interact with environmental variation is essential to predict the impacts of global change on forest communities. Here we investigated how resource-acquisition strategies, captured by branch and leaf traits, interact with environmental gradients, including climate, soil fertility, and solar radiation exposure, to influence relative growth rates (RGR) in 224 tree species from tropical montane forests in the Madidi region of the Bolivian Andes. Using data from 33 permanent forest plots and Bayesian hierarchical models, we found that the effects of environmental conditions on tree growth were modulated by species’ resource-acquisition strategies. Our findings reveal that acquisitive species, with higher specific leaf area (SLA), larger leaf size, and lower tissue density, performed better in cooler, drier, thermally variable, nutrient-rich sites with low solar radiation. In contrast, conservative species, characterized by stress-tolerant traits (higher tissue density and smaller leaves), grew better in nutrient-poor, high-radiation environments and tended to be less responsive to climatic gradients. Our analysis relied on two major PCA axes of functional trait covariation that captured distinct mechanistic pathways but aligned with survival-growth trade-off. Our results suggest that whole-plant allocation strategies, reflected by a leaf-area vs wood density trade-off may be more important than leaf-level traits (e.g., SLA) under closed canopies, highlighting the multidimensionality of trait-growth relationships. Our results underscore the role of trait–environment matching in shaping species performance and community assembly, and highlight the importance of trait-based approaches for forecasting forest responses to climate and land-use change. • Plant traits and environmental gradients interact to drive tree growth in the Andes. • Acquisitive species are more sensitive to climatic gradients than conservative ones. • Soil fertility favors acquisitive species whereas conservatives tolerate poor soils. • High solar exposure favors conservative species growth, limits acquisitive species. • Leaf area and wood density better predict growth compared to SLA in adult trees.
Phylogeny of Weinmannia (Cunoniaceae) reveals the contribution of the southern extratropics to tropical Andean biodiversity
(Elsevier BV, 2025) Ricardo A. Segovia; Eduardo Aguirre-Mazzi; Christine E. Edwards; Alexander G. Linan; A C.; Andrea Chaspuengal; Kyle G. Dexter; Francisco Fajardo‐Gutiérrez; William Farfán-Ríos; Nora H. Oleas
The evolutionary assembly of forest communities along environmental gradients: recent diversification or sorting of pre-adapted clades?
(2020) Alexander G. Linan; Jonathan A. Myers; Christine E. Edwards; Amy E. Zanne; Stephen A. Smith; Gabriel Arellano; Leslie Cayola; William Farfán-Ríos; A C.; Karina García‐Cabrera
Summary Biogeographic events occurring in the deep past can contribute to the structure of modern ecological communities. However, little is known about how the emergence of environmental gradients shape the evolution of species that underlie community assembly. In this study, we address how the creation of novel environments lead to community assembly via two non-mutually exclusive processes: 1) the immigration and ecological sorting of pre-adapted clades (ISPC), and 2) recent adaptive diversification (RAD). We study these processes in the context of the elevational gradient created by the uplift of the Central Andes. We develop a novel approach and method based on the decomposition of species turnover into within- and among-clade components, where clades correspond to lineages that originated before mountain uplift. Effects of ISPC and RAD can be inferred from how components of turnover change with elevation. We test our approach using data from over 500 Andean forest plots. We found that species turnover between communities at different elevations is dominated by the replacement of clades that originated before the uplift of the Central Andes. Our results suggest that immigration and sorting of clades pre-adapted to montane habitats is the primary mechanism shaping communities across elevations.
The evolutionary assembly of forest communities along environmental gradients: recent diversification or sorting of pre‐adapted clades?
(Wiley, 2021) Alexander G. Linan; Jonathan A. Myers; Christine E. Edwards; Amy E. Zanne; Stephen A. Smith; Gabriel Arellano; Leslie Cayola; William Farfán-Ríos; A C.; Karina García‐Cabrera
Recent studies have demonstrated that ecological processes that shape community structure and dynamics change along environmental gradients. However, much less is known about how the emergence of the gradients themselves shape the evolution of species that underlie community assembly. In this study, we address how the creation of novel environments leads to community assembly via two nonmutually exclusive processes: immigration and ecological sorting of pre-adapted clades (ISPC), and recent adaptive diversification (RAD). We study these processes in the context of the elevational gradient created by the uplift of the Central Andes. We develop a novel approach and method based on the decomposition of species turnover into within- and among-clade components, where clades correspond to lineages that originated before mountain uplift. Effects of ISPC and RAD can be inferred from how components of turnover change with elevation. We test our approach using data from over 500 Andean forest plots. We found that species turnover between communities at different elevations is dominated by the replacement of clades that originated before the uplift of the Central Andes. Our results suggest that immigration and sorting of clades pre-adapted to montane habitats is the primary mechanism shaping tree communities across elevations.