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Variation in species richness across the tree of life, accompanied by the incredible variety of ecological and morphological characteristics found in nature, has inspired many studies to link traits with species diversification. Angiosperms are a highly diverse group that has fundamentally shaped life on earth since the Cretaceous, and illustrate how species diversification affects ecosystem functioning. Numerous traits and processes have been linked to differences in species richness within this group, but we know little about their relative importance and how they interact. Here, we synthesised data from 152 studies that used state‐dependent speciation and extinction (SSE) models on angiosperm clades. Intrinsic traits related to reproduction and morphology were often linked to diversification but a set of universal drivers did not emerge as traits did not have consistent effects across clades. Importantly, SSE model results were correlated to data set properties – trees that were larger, older or less well‐sampled tended to yield trait‐dependent outcomes. We compared these properties to recommendations for SSE model use and provide a set of best practices to follow when designing studies and reporting results. Finally, we argue that SSE model inferences should be considered in a larger context incorporating species' ecology, demography and genetics. [ABSTRACT FROM AUTHOR]

Understanding the evolutionary dynamics of genetic diversity is fundamental for species conservation in the face of climate change, particularly in hyper-diverse biomes. Species in a region may respond similarly to climate change, leading to comparable evolutionary dynamics, or individualistically, resulting in dissimilar patterns. The second-largest expanse of continuous tropical rain forest (TRF) in the world is found in Central Africa. Here, present-day patterns of genetic structure are thought to be dictated by repeated expansion and contraction of TRFs into and out of refugia during Pleistocene climatic fluctuations. This refugia model implies a common response to past climate change. However, given the unrivalled diversity of TRFs, species could respond differently because of distinct environmental requirements or ecological characteristics. To test this, we generated genome-wide sequence data for >700 individuals of seven codistributed plants from Lower Guinea in Central Africa. We inferred species' evolutionary and demographic histories within a comparative phylogeographic framework. Levels of genetic structure varied among species and emerged primarily during the Pleistocene, but divergence events were rarely concordant. Demographic trends ranged from repeated contraction and expansion to continuous growth. Furthermore, patterns in genetic variation were linked to disparate environmental factors, including climate, soil, and habitat stability. Using a strict refugia model to explain past TRF dynamics is too simplistic. Instead, individualistic evolutionary responses to Pleistocene climatic fluctuations have shaped patterns in genetic diversity. Predicting the future dynamics of TRFs under climate change will be challenging, and more emphasis is needed on species ecology to better conserve TRFs worldwide. [ABSTRACT FROM AUTHOR]

Aim: Different species assemblages of annual killifish possess replicated body size distributions yet have unique sets of species in each area of endemism. Here, we use models of trait evolution and historical biogeography to discover how size variation originated and has been restructured. Location: South America. Taxon: Austrolebias (Cyprinodontiformes). Methods: We sampled 63 individuals from 26 Austrolebias species. Using phylogenetic trees (BEAST2), data on environmental variables at sampling locations and size data, we compare different models for trait evolution (SURFACE, l1OU) of body size and niche traits. We model the historical biogeography of the areas of endemism (BioGeoBEARS) and use both analyses in combination to reconstruct the history of four species assemblages. Results: We present new phylogenetic trees for Austrolebias and use them to show that large size principally arose within a single area driven by a shifted selection optimum for a subset of the species in that area. We suggest that ecological interactions triggered size divergence and that this large‐bodied lineage subsequently spread to two other areas. A second assemblage may have been shaped by adaptation to a new environment without an associated increase in size divergence. A third assemblage, which has the smallest size range and the most recent origin, is phylogenetically clustered, and we found no evidence of environmental filtering. Main conclusions: Assemblage similarity in Austrolebias is the result of contrasting ecological, evolutionary and historical processes. Modelling trait evolution together with historical biogeography can help to disentangle the complex histories of multispecies assemblages. This approach provides context to commonly used tests investigating the role of ecological processes from phylogenetic data and generates new testable hypotheses on the processes that generated trait diversity and assemblage similarity. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Hazelnut is consumed worldwide and is of critical economic importance to the rural communities of Turkey's northern coast. A new disease outbreak has drastically decreased yields across Turkey and climate change is emerging as a new threat to cultivation. Our study is the first to provide a genomic perspective on diversity in this vulnerable crop, which will prove valuable for future breeding efforts. Such research into perennial crops like hazelnut can help to improve farmer livelihoods and ensure the sustainability of crop production in a changing world. SummaryAssessing and describing genetic diversity in crop plants is a crucial first step toward their improvement. The European hazelnut, Corylus avellana L., is one of the most economically important tree nut crops worldwide. It is primarily produced in Turkey where rural communities depend on it for their livelihoods. Despite this, we know little about its domestication history and the genetic diversity it holds.We use double digest restriction‐site associated DNA (ddRAD) sequencing to produce a genome‐wide dataset containing wild and domesticated hazelnut. We uncover patterns of population structure and diversity, determine levels of crop‐wild gene flow, and estimate the relationships among different genetic clusters.We use a dataset of over 60k single nucleotide polymorphisms to find that genetic clusters of cultivars do not reflect their given names and that there is limited evidence for a reduction in genetic diversity in domesticated individuals. We find evidence that hazelnut may have been domesticated more than once and that admixture has likely occurred multiple times between wild and domesticated hazelnut.We provide the first genomic assessment of Turkish hazelnut diversity and suggest that there has not been an extreme bottleneck during the domestication of this crop, leading to cultivars at different stages of domestication. Our study provides a platform for further research that will protect hazelnut from the threats of climate change and an emerging fungal disease. [ABSTRACT FROM AUTHOR]