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Aim: Globally, biodiversity is unevenly distributed, as a result of varying environmental conditions and regionally different historical processes. The influence of the latter on current diversity patterns is poorly understood. We explore geographic patterns of matches and mismatches between phylogenetic relatedness metrics measuring different depths of evolutionary history and investigate the effects of evolutionary legacy at different evolutionary depths on species density of ferns. Methods: We divided the globe into 392 geographic regions on land, and collated species lists of ferns for each geographic region. We related species richness to phylogenetic metrics reflecting different depths of evolutionary history (standardized effect sizes of mean nearest taxon distance and mean pairwise distance, MNTDses and MPDses, respectively) for ferns in regional floras across the world. Location: Global. Time Period: Current. Taxon: Ferns. Results: We show that different centers of fern diversity have strikingly different phylogenetic composition. We find that overall fern species diversity is negatively correlated with both MNTDses and MPDses, so that regions with high species diversity tend to have clustered species assemblages, whereas species‐poor regions tend to have overdispersed species assemblages. At the global extent, MNTDses and MPDses together explained 62.2%, 19.3%, and 65.7% of the variation in species diversity for all ferns as a whole, non‐polypod ferns, and polypods, respectively. Main Conclusions: Our study suggests that current geographic patterns of fern species richness are driven, at least in part, by evolutionary history of ferns, which varies among biogeographic regions. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Location Taxon Methods Results Main Conclusions Endemic species, characterised by limited geographic ranges, face a high risk of extinction. The neotropical region harbours diverse ecosystems and a substantial number of endemic species, thus identifying areas of high endemism is crucial for protecting unique and threatened species and ecosystems. Vascular epiphytes—nonparasitic plants that grow on other plants without contact with the soil—exhibit remarkable diversity in the neotropics, with 63% of the global total of ca. 31,000 epiphyte species found in this region. This study aims to describe the endemism centres for the five most species‐rich families of vascular epiphytes.Neotropics.Tracheophyta.We gathered information from free‐access web repositories, specific epiphytic plant databases and scientific and grey literature on epiphyte species of the families Araceae, Bromeliaceae, Orchidaceae, Piperaceae and Polypodiaceae within the neotropical realm as defined by Morrone et al. (2022). Geographical ranges were calculated using minimum convex polygons for 11,446 species, accounting for about 70% of all epiphyte species in the neotropics. Narrow endemic species were defined as those within the first quartile of the density distribution of geographic range sizes within each family and we identified endemism centres for epiphyte species of the five families.Our study identified endemism centres for vascular epiphyte species in several biogeographic provinces, including Paramo, Cauca, Guatuso‐Talamanca, Atlantic, Yungas and Puntarenas‐Chiriqui. Orchidaceae, accounting for most of the analysed species (71%), drove the overall distribution pattern; however, endemism patterns varied among families.Regions with high epiphyte richness exhibited a greater proportion of endemic species, though the composition of epiphyte species varied considerably among regions. The endemism centres identified in this study could be prioritised as conserved and protected areas. [ABSTRACT FROM AUTHOR]

Aim Location Taxon Methods Results Main Conclusions Investigating phylogenetic beta diversity, and its turnover and nestedness components, can shed light on the evolutionary causes shaping the similarity (or dissimilarity) in composition between biological assemblages. Liverworts are important constituents of most terrestrial ecosystems worldwide but studies on phylogenetic beta diversity in liverworts are scarce. Here, we explore geographic patterns of phylogenetic beta diversity and its two components in liverworts across the world and evaluate the relative importance of dispersal limitation and environmental filtering processes in shaping beta diversity patterns at different spatial extents by relating phylogenetic beta diversity or phylogenetic turnover to geographic and climatic distances.Global.Liverworts.We conducted correlation and regression analyses to relate phylogenetic beta diversity and its two components (turnover and nestedness) to six variables representing current climate conditions and two variables representing historical (Quaternary) climate change, and to geographic and climatic distances at different spatial extents (global, continental, and regional).We found that of the eight variables of current and historical climates considered, precipitation seasonality was the strongest determinant of phylogenetic beta diversity in liverworts. At the global extent, geographic and climatic distances explained similar amounts of the variation in phylogenetic turnover, whereas at the continental extent, climatic distance explained more variation than geographic distance in five of the seven continents, and at a regional extent (roughly a circle of 4000 km in diameter), geographic distances generally had a greater effect than climatic distance on phylogenetic turnover.We conclude that both dispersal limitation and environmental filtering played an important role in shaping phylogenetic structure of liverwort floras, but their relative importance varies at different spatial scales and among geographic regions. [ABSTRACT FROM AUTHOR]