Extracted from the Mendeley GBIF Public Library.
Bocksberger G, Schnitzler J, Chatelain C, Daget P, Janssen T, Schmidt M et al. (2016)
Journal of Vegetation Science.
Questions Which environmental variables influence grass diversity in West Africa? What are the effects of climate and grass functional traits on the spatial patterns (richness and abundance) of the grass clades Andropogoneae, Paniceae and Chloridoideae? Location West Africa, demarcated by the Atlantic Ocean in the west and south (20° W and 4° N), the Sahara desert in the north (25° N) and the border between Niger and Chad in the east (20° E). Methods Based on 38 912 georeferenced occurrence records, we modelled the distribution of 302 grass species (51% of West African grass diversity). We integrated species richness, abundance and functional traits (life cycle, photosynthetic type and height) to determine the contribution of the most speciose grass clades (Andropogoneae, Paniceae and Chloridoideae) to overall grass diversity in West Africa. Results Precipitation is the variable most often influencing the species distribution models of grasses in West Africa. Richness and relative abundance of the tribe Andropogoneae show a centre of diversity in Sudanian savanna regions. The height of Andropogoneae species, generally >150 cm, is driving this ecological dominance. Species richness of the tribe Paniceae is more dispersed and shows two main centres of abundance: The southern regions with higher mean annual precipitation and tree density are dominated by C3 Paniceae species. The Sahelian regions in the north are dominated by short Paniceae species with the C4 NAD-ME photosynthetic subtype, as well as Chloridoideae possessing the same functional attributes. Conclusions Our study provides insight into the environmental correlates of grass species richness in West Africa and contributes to the much-needed research on tropical rangelands. Moreover, the integration of evolutionary history significantly improves our understanding of large-scale biodiversity patterns.
Keywords: Andropogoneae, Chloridoideae, Maxent, Paniceae, Poaceae, Savanna, Species distribution modelling, West Africa, species richness
Boucher F, Lavergne S, Basile M, Choler P, Aubert S (2016)
Perspectives in Plant Ecology, Evolution and Systematics 20 22-31.
Cushion-forming species occur in all cold and dry environments worldwide, where they play important engineering roles. Understanding the origins of cushion plants may thus provide insights into the evolutionary assembly of biomes under extreme climatic conditions. Here we investigate the evolutionary and biogeographic history of cushions in Angiosperms based on a global checklist of all cushion plants, along with phylogenetic, climatic, and biogeographic information. Our aim is to measure the frequency of this evolutionary convergence and to identify its historic, environmental, and biogeographic drivers. We show that cushions appeared at least 115 times in Angiosperms and that they mainly belong to families that occupy the coldest and driest environments on Earth. We found that cushions have intensively diversified in the Himalayas, the Andes, or New Zealand, while other regions like Patagonia have probably been hubs enabling cushion species to migrate between different alpine regions. We conclude that the cushion life form is a remarkable example of convergent key innovation, which has favored the colonization of cold and dry habitats.
Keywords: Alpine, Angiosperms, Arctic, Biogeography, Cushion plants, Evolutionary convergence
Ferreira G, Ferreira P, Chautems A, Waechter J (2016)
Subtropical species of Sinningia (Gesneriaceae): distribution patterns and limiting environmental factors
Flora - Morphology, Distribution, Functional Ecology of Plants 222 86-95.
The neotropical genus Sinningia Nees encompasses tuberous herbs or subshrubs which occupy a wide range of environments with respect to climate and soil or substrate types. The genus has more than 70 species distributed from Southern Mexico to Northern Argentina, with a diversity centre in the Brazilian Atlantic Rainforest. In this ecosystem, a large number of species occur in several particular vegetation types, occupying terrestrial, rupestrial and epiphytic substrates. The aims of this study were to describe the distribution patterns of subtropical Sinningia species, and to determine possible limiting factors for their range extension. We summarized environmental data for 21 subtropical species. Ten geographical and ecological variables were subdivided into several regional or local conditions. The occurrence of species in each of these conditions was obtained from published material, herbarium reviews and field expeditions. We used exploratory multivariate approaches, (cluster and ordination analyses) to assess the contribution of these variables to species’ ecological and geographical distributions. Comparisons between groups of species were evaluated using randomization tests. Two major patterns of geographic distribution were identified for subtropical Sinningia species: widespread and restricted. Species richness according to spatial and climatic variables showed four distinct patterns. Habitat tolerance of the species also distinguished two groups in a wider continuum context. Cluster analysis resulted in two stable groups, which coincided almost entirely with an a priori classification based on geographic range. Ordination analysis showed a distinction between widespread and restricted species, as well as a gradient of substrate occupancy. Patterns of ecological and geographical distribution were strongly related to the evolutionary history of the genus. The southern distribution limit of Sinningia is mainly linked to shifts in vegetation types around the 30°S parallel, where the northern forested Atlantic and Paranean biogeographic provinces give place to the southern non-forested Espinal and Pampean provinces.
Keywords: Biogeography, Corytholoma, Dircaea, Ecology, Plasticity
Lee-Yaw J, Kharouba H, Bontrager M, Mahony C, Csergő A, Noreen A et al. (2016)
A synthesis of transplant experiments and ecological niche models suggests that range limits are often niche limits
Global change has made it important to understand the factors that shape species' distributions. Central to this area of research is the question of whether species' range limits primarily reflect the distribution of suitable habitat (i.e. niche limits) or arise as a result of dispersal limitation. Over-the-edge transplant experiments and ecological niche models are commonly used to address this question, yet few studies have taken advantage of a combined approach for inferring the causes of range limits. Here, we synthesise results from existing transplant experiments with new information on the predicted suitability of sites based on niche models. We found that individual performance and habitat suitability independently decline beyond range limits across multiple species. Furthermore, inferences from transplant experiments and niche models were generally concordant within species, with 31 out of 40 cases fully supporting the hypothesis that range limits are niche limits. These results suggest that range limits are often niche limits and that the factors constraining species' ranges operate at scales detectable by both transplant experiments and niche models. In light of these findings, we outline an integrative framework for addressing the causes of range limits in individual species.
Keywords: Abiotic constraints, climate, dispersal limitation, fitness, geographical distribution, over the edge transplant, species distribution modelling
Onstein R, Peter Linder H (2016)
Beyond climate: convergence in fast evolving sclerophylls in Cape and Australian Rhamnaceae predates the mediterranean climate
Journal of Ecology.
Morphological convergence in mediterranean-type ecosystems (MTEs) has long been interpreted as adaptation to climatic similarities among the five MTEs of the world. Here, we challenge this model using the globally distributed Rhamnaceae. We collected functional trait data (specific leaf area, leaf area, spinescence, leaf phenology, growth form and leaf margin type) and biome data to test for trait convergence in MTEs, for models of trait evolution and ancestral state reconstruction and for the effect of traits on speciation and extinction rates, using a phylogenetic framework. We show that leaf functional traits evolve to three optima, which correspond to (a) the edaphically specialized Australian and Cape MTEs (AC), (b) the mediterranean-type climates, but edaphically normal Chile, California and Mediterranean Basin (CCM), and (c) the non-mediterranean habitats. We find that Rhamnaceae in CCM are predominantly characterized by non-sclerophylly, the ancestral state in Rhamnaceae, and Rhamnaceae in AC by sclerophylly. These leaf character syndromes have evolved prior to mediterranean climates in MTEs, thereby failing to be adaptive to this selective regime. However, sclerophylly evolved contemporaneously with the transitions to AC, and may therefore be an adaptation to nutrient-poor soils. The evolution of sclerophylly has contributed to increased diversification rates of Pomaderreae in Australia and Phyliceae in the Cape, by reducing extinction rates and thereby facilitating evolutionary persistence. The historical relatively stable conditions in AC are consistent with this persistence hypothesis. Synthesis. In this study we integrate the fields of macroevolution and ecology and show that low extinction rates may not only account for the ecological, but also for the floristic dominance of sclerophylly in the hyperdiverse Australian and Cape mediterranean-type ecosystems.
Keywords: Cape flora, character syndrome, diversification rate, extinction rate, fynbos, kwongan, plant-climate interactions, sclerophylly, specific leaf area
Antonelli A, Zizka A, Silvestro D, Scharn R, Cascales-Miñana B, Bacon C (2015)
An engine for global plant diversity: highest evolutionary turnover and emigration in the American tropics.
Frontiers in genetics 6 130.
Understanding the processes that have generated the latitudinal biodiversity gradient and the continental differences in tropical biodiversity remains a major goal of evolutionary biology. Here we estimate the timing and direction of range shifts of extant flowering plants (angiosperms) between tropical and non-tropical zones, and into and out of the major tropical regions of the world. We then calculate rates of speciation and extinction taking into account incomplete taxonomic sampling. We use a recently published fossil calibrated phylogeny and apply novel bioinformatic tools to code species into user-defined polygons. We reconstruct biogeographic history using stochastic character mapping to compute relative numbers of range shifts in proportion to the number of available lineages through time. Our results, based on the analysis of c. 22,600 species and c. 20 million geo-referenced occurrence records, show no significant differences between the speciation and extinction of tropical and non-tropical angiosperms. This suggests that at least in plants, the latitudinal biodiversity gradient primarily derives from other factors than differential rates of diversification. In contrast, the outstanding species richness found today in the American tropics (the Neotropics), as compared to tropical Africa and tropical Asia, is associated with significantly higher speciation and extinction rates. This suggests an exceedingly rapid evolutionary turnover, i.e., Neotropical species being formed and replaced by one another at unparalleled rates. In addition, tropical America stands out from other continents by having "pumped out" more species than it received through most of the last 66 million years. These results imply that the Neotropics have acted as an engine for global plant diversity.
Keywords: Angiosperms, Latitudinal diversity gradient, biogeography, diversification rates, evolution, phylogenetics, tropical biodiversity
Bone R, Smith J, Arrigo N, Buerki S (2015)
A macro-ecological perspective on crassulacean acid metabolism (CAM) photosynthesis evolution in Afro-Madagascan drylands: Eulophiinae orchids as a case study.
The New phytologist.
Crassulacean acid metabolism (CAM) photosynthesis is an adaptation to water and atmospheric CO2 deficits that has been linked to diversification in dry-adapted plants. We investigated whether CAM evolution can be associated with the availability of new or alternative niches, using Eulophiinae orchids as a case study. Carbon isotope ratios, geographical and climate data, fossil records and DNA sequences were used to: assess the prevalence of CAM in Eulophiinae orchids; characterize the ecological niche of extant taxa; infer divergence times; and estimate whether CAM is associated with niche shifts. CAM evolved in four terrestrial lineages during the late Miocene/Pliocene, which have uneven diversification patterns. These lineages originated in humid habitats and colonized dry/seasonally dry environments in Africa and Madagascar. Additional key features (variegation, heterophylly) evolved in the most species-rich CAM lineages. Dry habitats were also colonized by a lineage that includes putative mycoheterotrophic taxa. These findings indicate that the switch to CAM is associated with environmental change. With its suite of adaptive traits, this group of orchids represents a unique opportunity to study the adaptations to dry environments, especially in the face of projected global aridification.
Keywords: Africa, Eulophiinae, Madagascar, Orchidaceae, climate change, crassulacean acid metabolism (CAM) photosynthesis, shift of niche
Dikow T, Agosti D (2015)
Utilizing online resources for taxonomy: a cybercatalog of Afrotropical apiocerid flies (Insecta: Diptera: Apioceridae).
Biodiversity data journal 3(3) e5707.
A cybercatalog to the Apioceridae (apiocerid flies) of the Afrotropical Region is provided. Each taxon entry includes links to open-access, online repositories such as ZooBank, BHL/BioStor/BLR, Plazi, GBIF, Morphbank, EoL, and a research web-site to access taxonomic information, digitized literature, morphological descriptions, specimen occurrence data, and images. Cybercatalogs as the one presented here will need to become the future of taxonomic catalogs taking advantage of the growing number of online repositories, linked data, and be easily updatable. Comments on the deposition of the holotype of Apiocera braunsi Melander, 1907 are made.
Keywords: cybertaxonomy, online repositories, open-access
Fernández M, Navarro L, Apaza-Quevedo A, Gallegos S, Marques A, Zambrana-Torrelio C et al. (2015)
Pragmatic methods to assess the status of biodiversity at multiple scales are required to support conservation decision-making. At the intersection of several major biogeographic zones, Bolivia has extraordinary potential to develop a monitoring strategy aligned with the objectives of the Group on Earth Observations Biodiversity Observation Network (GEO BON). Bolivia, a GEO Observer since 2005, is already working on the adequacy of national earth observations towards the objectives of the Global Earth Observation System of Systems (GEOSS). However, biodiversity is still an underrepresented component in this initiative. The integration of biodiversity into Bolivia’s GEO framework would confirm the need for a country level biodiversity monitoring strategy, fundamental to assess the progress towards the 2020 Aichi targets. Here we analyse and discuss two aspects of the process of developing such a strategy: (1) identification of taxonomic, temporal and spatial coverage of biodiversity data to detect both ava...
Keywords: Bolivia, GEO BON, baseline, big data integration, biodiversity, monitoring
Gallien L, Saladin B, Boucher F, Richardson D, Zimmermann N (2015)
The New phytologist.
Why are some introduced species more successful at establishing and spreading than others? Until now, characteristics of extant species have been intensively investigated to answer this question. We propose to gain new insights on species invasiveness by exploring the long-term biogeographic and evolutionary history of lineages. We exemplify our approach using one of the best-studied invasive plant genera, Pinus. We notably estimated the historical biogeography of pines and the rates of trait evolution in pines. These estimates were analysed with regard to species invasiveness status. The results revealed that currently invasive species belong to lineages that were particularly successful at colonizing new regions in the past. We also showed that highly mobile lineages had faster rates of niche evolution, but that these rates are poor proxies for species adaptive potential in invaded regions (estimated by niche shift among native and invaded regions). In summary, working at the interface of ecology, historical biogeography and evolutionary history offers stimulating perspectives to improve our understanding of the drivers of invasion success.
Keywords: Pinus, biological invasions, evolutionary history, invasiveness, migration, model averaging, niche shift, tree invasions