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Sökning: WFRF:(Zizka A.)

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  • Kattge, Jens, et al. (författare)
  • TRY plant trait database - enhanced coverage and open access
  • 2020
  • Ingår i: Global Change Biology. - : Wiley-Blackwell. - 1354-1013 .- 1365-2486. ; 26:1, s. 119-188
  • Tidskriftsartikel (refereegranskat)abstract
    • Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives.
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10.
  • Ralimanana, H., et al. (författare)
  • Madagascar’s extraordinary biodiversity: Threats and opportunities
  • 2022
  • Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 378:6623
  • Forskningsöversikt (refereegranskat)abstract
    • Madagascar’s unique biota is heavily affected by human activity and is under intense threat. Here, we review the current state of knowledge on the conservation status of Madagascar’s terrestrial and freshwater biodiversity by presenting data and analyses on documented and predicted species-level conservation statuses, the most prevalent and relevant threats, ex situ collections and programs, and the coverage and comprehensiveness of protected areas. The existing terrestrial protected area network in Madagascar covers 10.4% of its land area and includes at least part of the range of the majority of described native species of vertebrates with known distributions (97.1% of freshwater fishes, amphibians, reptiles, birds, and mammals combined) and plants (67.7%). The overall figures are higher for threatened species (97.7% of threatened vertebrates and 79.6% of threatened plants occurring within at least one protected area). International Union for Conservation of Nature (IUCN) Red List assessments and Bayesian neural network analyses for plants identify overexploitation of biological resources and unsustainable agriculture as the most prominent threats to biodiversity. We highlight five opportunities for action at multiple levels to ensure that conservation and ecological restoration objectives, programs, and activities take account of complex underlying and interacting factors and produce tangible benefits for the biodiversity and people of Madagascar.
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11.
  • Zizka, A., et al. (författare)
  • No one-size-fits-all solution to clean GBIF
  • 2020
  • Ingår i: Peerj. - : PeerJ. - 2167-8359. ; 8
  • Tidskriftsartikel (refereegranskat)abstract
    • Species occurrence records provide the basis for many biodiversity studies. They derive from georeferenced specimens deposited in natural history collections and visual observations, such as those obtained through various mobile applications. Given the rapid increase in availability of such data, the control of quality and accuracy constitutes a particular concern. Automatic filtering is a scalable and reproducible means to identify potentially problematic records and tailor datasets from public databases such as the Global Biodiversity Information Facility (GBIF; http://www.gbif.org), for biodiversity analyses. However, it is unclear how much data may be lost by filtering, whether the same filters should be applied across all taxonomic groups, and what the effect of filtering is on common downstream analyses. Here, we evaluate the effect of 13 recently proposed filters on the inference of species richness patterns and automated conservation assessments for 18 Neotropical taxa, including terrestrial and marine animals, fungi, and plants downloaded from GBIF. We find that a total of 44.3% of the records are potentially problematic, with large variation across taxonomic groups (25-90%). A small fraction of records was identified as erroneous in the strict sense (4.2%), and a much larger proportion as unfit for most downstream analyses (41.7%). Filters of duplicated information, collection year, and basis of record, as well as coordinates in urban areas, or for terrestrial taxa in the sea or marine taxa on land, have the greatest effect. Automated filtering can help in identifying problematic records, but requires customization of which tests and thresholds should be applied to the taxonomic group and geographic area under focus. Our results stress the importance of thorough recording and exploration of the meta-data associated with species records for biodiversity research.
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12.
  • Antonelli, Alexandre, 1978, et al. (författare)
  • Madagascar's extraordinary biodiversity : Evolution, distribution, and use
  • 2022
  • Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 378:6623, s. 962-
  • Tidskriftsartikel (refereegranskat)abstract
    • Madagascar's biota is hyperdiverse and includes exceptional levels of endemicity. We review the current state of knowledge on Madagascar's past and current terrestrial and freshwater biodiversity by compiling and presenting comprehensive data on species diversity, endemism, and rates of species description and human uses, in addition to presenting an updated and simplified map of vegetation types. We report a substantial increase of records and species new to science in recent years; however, the diversity and evolution of many groups remain practically unknown (e.g., fungi and most invertebrates). Digitization efforts are increasing the resolution of species richness patterns and we highlight the crucial role of field- and collections-based research for advancing biodiversity knowledge and identifying gaps in our understanding, particularly as species richness corresponds closely to collection effort. Phylogenetic diversity patterns mirror that of species richness and endemism in most of the analyzed groups. We highlight humid forests as centers of diversity and endemism because of their role as refugia and centers of recent and rapid radiations. However, the distinct endemism of other areas, such as the grassland-woodland mosaic of the Central Highlands and the spiny forest of the southwest, is also biologically important despite lower species richness. The documented uses of Malagasy biodiversity are manifold, with much potential for the uncovering of new useful traits for food, medicine, and climate mitigation. The data presented here showcase Madagascar as a unique " living laboratory" for our understanding of evolution and the complex interactions between people and nature. The gathering and analysis of biodiversity data must continue and accelerate if we are to fully understand and safeguard this unique subset of Earth's biodiversity.
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13.
  • Belluardo, F., et al. (författare)
  • Slow and steady wins the race: Diversification rate is independent from body size and lifestyle in Malagasy skinks (Squamata: Scincidae: Scincinae)
  • 2023
  • Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903. ; 178
  • Tidskriftsartikel (refereegranskat)abstract
    • Most of the unique and diverse vertebrate fauna that inhabits Madagascar derives from in situ diversification from colonisers that reached this continental island through overseas dispersal. The endemic Malagasy Scincinae lizards are amongst the most species-rich squamate groups on the island. They colonised all bioclimatic zones and display many ecomorphological adaptations to a fossorial (burrowing) lifestyle. Here we propose a new phylogenetic hypothesis for their diversification based on the largest taxon sampling so far compiled for this group. We estimated divergence times and investigated several aspects of their diversification (diversification rate, body size and fossorial lifestyle evolution, and biogeography). We found that diversification rate was constant throughout most of the evolutionary history of the group, but decreased over the last 6-4 million years and independently from body size and fossorial lifestyle evolution. Fossoriality has evolved from fully quadrupedal ancestors at least five times independently, which demonstrates that even complex morphological syndromes - in this case involving traits such as limb regression, body elongation, modification of cephalic scalation, depigmentation, and eyes and ear-opening regression - can evolve repeatedly and independently given enough time and eco-evolutionary advantages. Initial diversification of the group likely occurred in forests, and the divergence of sand-swimmer genera around 20 Ma appears linked to a period of aridification. Our results show that the large phenotypic variability of Malagasy Scincinae has not influenced diversification rate and that their rich species diversity results from a constant accumulation of lineages through time. By compiling large geographic and trait-related datasets together with the computation of a new time tree for the group, our study contributes important insights on the diversification of Malagasy vertebrates.
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14.
  • Rozzi, R., et al. (författare)
  • Dwarfism and gigantism drive human-mediated extinctions on islands
  • 2023
  • Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 379:6636, s. 1054-1058
  • Tidskriftsartikel (refereegranskat)abstract
    • Islands have long been recognized as distinctive evolutionary arenas leading to morphologically divergent species, such as dwarfs and giants. We assessed how body size evolution in island mammals may have exacerbated their vulnerability, as well as how human arrival has contributed to their past and ongoing extinctions, by integrating data on 1231 extant and 350 extinct species from islands and paleo islands worldwide spanning the past 23 million years. We found that the likelihood of extinction and of endangerment are highest in the most extreme island dwarfs and giants. Extinction risk of insular mammals was compounded by the arrival of modern humans, which accelerated extinction rates more than 10-fold, resulting in an almost complete demise of these iconic marvels of island evolution.
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  • Pérez-Escobar, O. A., et al. (författare)
  • The Andes through time: evolution and distribution of Andean floras
  • 2022
  • Ingår i: Trends in Plant Science. - : Elsevier BV. - 1360-1385. ; 27:4, s. 364-378
  • Tidskriftsartikel (refereegranskat)abstract
    • The Andes are the world's most biodiverse mountain chain, encompassing a complex array of ecosystems from tropical rainforests to alpine habitats. We provide a synthesis of Andean vascular plant diversity by estimating a list of all species with publicly available records, which we integrate with a phylogenetic dataset of 14 501 Neotropical plant species in 194 clades. We find that (i) the Andean flora comprises at least 28 691 georeferenced species documented to date, (ii) Northern Andean mid-elevation cloud forests are the most species-rich Andean ecosystems, (iii) the Andes are a key source and sink of Neotropical plant diversity, and (iv) the Andes, Amazonia, and other Neotropical biomes have had a considerable amount of biotic interchange through time.
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  • Tedersoo, Leho, et al. (författare)
  • Global patterns in endemicity and vulnerability of soil fungi.
  • 2022
  • Ingår i: Global change biology. - : Wiley. - 1365-2486 .- 1354-1013. ; 28:22, s. 6696-6710
  • Tidskriftsartikel (refereegranskat)abstract
    • Fungi are highly diverse organisms, which provide multiple ecosystem services. However, compared with charismatic animals and plants, the distribution patterns and conservation needs of fungi have been little explored. Here, we examined endemicity patterns, global change vulnerability and conservation priority areas for functional groups of soil fungi based on six global surveys using a high-resolution, long-read metabarcoding approach. We found that the endemicity of all fungi and most functional groups peaks in tropical habitats, including Amazonia, Yucatan, West-Central Africa, Sri Lanka, and New Caledonia, with a negligible island effect compared with plants and animals. We also found that fungi are predominantly vulnerable to drought, heat and land-cover change, particularly in dry tropical regions with high human population density. Fungal conservation areas of highest priority include herbaceous wetlands, tropical forests, and woodlands. We stress that more attention should be focused on the conservation of fungi, especially root symbiotic arbuscular mycorrhizal and ectomycorrhizal fungi in tropical regions as well as unicellular early-diverging groups and macrofungi in general. Given the low overlap between the endemicity of fungi and macroorganisms, but high conservation needs in both groups, detailed analyses on distribution and conservation requirements are warranted for other microorganisms and soil organisms.
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  • Schmidt, M., et al. (författare)
  • Diversity, distribution and preliminary conservation status of the flora of Burkina Faso
  • 2017
  • Ingår i: Phytotaxa. - : Magnolia Press. - 1179-3155 .- 1179-3163. ; 304:1, s. 1-215
  • Tidskriftsartikel (refereegranskat)abstract
    • West Africa is a floristically understudied region that is facing severe environmental changes in the 21 st century. Basic distribution data and information on the conservation status for most plant species of the region are scarce, and good information only exists for small areas of interest or for key species. This lack of knowledge seriously hampers urgently needed regional conservation efforts. Here we present comprehensive distribution information and preliminary, automated species conservation assessments for the flora of Burkina Faso, a country in tropical West Africa with a flora and vegetation typical for the savanna belt of the region. We documented and analysed the distribution of 1,568 species or 80% of the flora of Burkina Faso based on an expert curated dataset comprising ca. 150,000 occurrence records from herbarium specimens and vegetation surveys. We used this dataset and environmental niche models to calculate three indicator variables for a preliminary, automated conservation assessment. We classified 350 species (18% of the flora, excluding introduced species) as potentially "Critically Endangered", "Endangered", "Vulnerable" or "Near-Threatened" on the national level. The analyses confirmed species-rich areas in the south-west and south-east of the country, and showed a particular concentration of potentially Endangered species in the south. Furthermore, the proportion of potentially Endangered species differed between plant families, growth forms and habitats. Our results set the base for further plant geographical and ecological studies and are a data-driven baseline for further conservation assessments and large scale conservation strategies of the West African flora.
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  • Torres Jimenez, Maria Fernanda, et al. (författare)
  • Phylogenomics of the Palm Tribe Lepidocaryeae (Calamoideae: Arecaceae) and Description of a New Species of Mauritiella
  • 2021
  • Ingår i: Systematic Botany. - : American Society of Plant Taxonomists. - 0363-6445. ; 46:3, s. 863-874
  • Tidskriftsartikel (refereegranskat)abstract
    • The palm tribe Lepidocaryeae (Arecaceae) comprises seven genera and 51 currently accepted species that are distributed in lowland tropical forests and savannas across Africa and the Americas. Subtribal relationships within Lepidocaryeae have been a persistent challenge, limiting our understanding of its systematics, morphology, and biogeography. Several aspects make the tribe an ideal system to study plant evolution and diversity: it is well-represented in the fossil record as a prolific pollen producer, its continental diversity contradicts common biodiversity patterns of lower species richness in Africa in comparison to South America, and it contains one of the most abundant Amazonian tree species, Mauritia flexuosa. Here, we investigated the systematics of the tribe by sampling 122 individuals representing 42 species (82% of the tribe), using target sequence capture. We recovered nearly 10,000 single nucleotide polymorphisms from nuclear and plastid DNA across 146 target sequences to separately infer a phylogenomic tree. Our results strongly support inter-generic and inter-specific relationships, where a majority of nodes were resolved with over 90% bootstrap support. We also identify strong phylogenetic support for the recognition of a new species from central and south Amazonia, Mauritiella disticha. The distichous phyllotaxy is diagnostic of the species within the genus. Rare and currently only known from the middle-lower Madeira River basin in the state of Amazonas, Brazil, M. disticha is restricted to open vegetation and forest edges growing in white sand habitats with saturated or well-drained soils. Our preliminary red list assessment suggests its threatened status to be vulnerable (VU). We use our phylogenomic inference to define and contextualize systematic relationships in the tribe, and present a formal species description.
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  • Zizka, A., et al. (författare)
  • Biogeography and conservation status of the pineapple family (Bromeliaceae)
  • 2020
  • Ingår i: Diversity and Distributions. - : Wiley. - 1366-9516 .- 1472-4642. ; 26:2, s. 183-95
  • Tidskriftsartikel (refereegranskat)abstract
    • Aim To provide distribution information and preliminary conservation assessments for all species of the pineapple family (Bromeliaceae), one of the most diverse and ecologically important plant groups of the American tropics-a global biodiversity hotspot. Furthermore, we aim to analyse patterns of diversity, endemism and the conservation status of the Bromeliaceae on the continental level in the light of their evolutionary history. Location The Americas. Methods We compiled a dataset of occurrence records for 3,272 bromeliad species (93.4% of the family) and modelled their geographic distribution using either climate-based species distribution models, convex hulls or geographic buffers dependent on the number of occurrences available. We then combined this data with information on taxonomy and used the ConR software for a preliminary assessment of the conservation status of all species following Criterion B of the International Union for the Conservation of Nature (IUCN). Results Our results stress the Atlantic Forest in eastern Brazil, the Andean slopes, Central America and the Guiana Highlands as centres of bromeliad diversity and endemism. Phylogenetically ancient subfamilies of bromeliads are centred in the Guiana highlands whereas the large radiations of the group spread across different habitats and large geographic area. A total of 81% of the evaluated bromeliad species are Possibly Threatened with extinction. We provide range polygons for 3,272 species, as well as newly georeferenced point localities for 911 species in the novel "bromeliad" r package, together with functions to generate diversity maps for individual taxonomic or functional groups. Main conclusions Diversity centres of the Bromeliaceae agreed with macroecological patterns of other plant and animal groups, but show some particular patterns related to the evolutionary origin of the family, especially ancient dispersal corridors. A staggering 2/3rds of Bromeliaceae species might be threatened with extinction, especially so in tropical rain forests, raising concerns about the conservation of the family and bromeliad-dependent animal species.
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20.
  • Zizka, Alexander, 1986, et al. (författare)
  • The vascular plant diversity of Burkina Faso (West Africa) - a quantitative analysis and implications for conservation
  • 2015
  • Ingår i: Candollea. - : Society of Conservatoire at Jardin Botaniques de la Ville de Geneve. - 0373-2967. ; 70:1, s. 9-20
  • Tidskriftsartikel (refereegranskat)abstract
    • Based on a species inventory and the related distribution dataset, the authors present a quantitative analysis of the vascular plant diversity of Burkina Faso (BFA) and its four phytogeographic zones. We analyzed species richness, higher taxon diversity, life forms, chorological types, introduced species, habitat preferences and the number of rare species. The flora of BFA comprises 1972 non-cultivated vascular plant species in 752 genera and 145 families. Species richness and plant family richness are highest in the South Sudanian zone in the South of the country Fabaceae, Poaceae and Cyperaceae are the most species rich plant families. Only one species (Isoetes jaegeri Pitot) is endemic to the country, whereas the vast majority occurs throughout Africa. The flora is dominated by therophytes and phanerophytes. Our results show a good representation of the West African flora in BFA. The flora and vegetation of the four phytogeographic zones within BFA is determined by the latitudinal climatic gradient of the region. The relative number of phanerophytes and forest species decrease along the gradient, while the relative number of therophytes increase. Based on the specimen record we classified 38% of the plant species as "rare" to BFA. The analyses show that the south-west of BFA is a center of national biodiversity and a potential "hotspot" for conservation. In addition to its high species richness this area harbors the highest number of rare species (409 species, 29%) including the endemic species.
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21.
  • Zizka, Alexander, 1986, et al. (författare)
  • Traditional plant use in Burkina Faso (West Africa): a national-scale analysis with focus on traditional medicine
  • 2015
  • Ingår i: Journal of Ethnobiology and Ethnomedicine. - : Springer Science and Business Media LLC. - 1746-4269. ; 11:9
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: The West African country of Burkina Faso (BFA) is an example for the enduring importance of traditional plant use today. A large proportion of its 17 million inhabitants lives in rural communities and strongly depends on local plant products for their livelihood. However, literature on traditional plant use is still scarce and a comprehensive analysis for the country is still missing. Methods: In this study we combine the information of a recently published plant checklist with information from ethnobotanical literature for a comprehensive, national scale analysis of plant use in Burkina Faso. We quantify the application of plant species in 10 different use categories, evaluate plant use on a plant family level and use the relative importance index to rank all species in the country according to their usefulness. We focus on traditional medicine and quantify the use of plants as remedy against 22 classes of health disorders, evaluate plant use in traditional medicine on the level of plant families and rank all species used in traditional medicine according to their respective usefulness. Results: A total of 1033 species (50%) in Burkina Faso had a documented use. Traditional medicine, human nutrition and animal fodder were the most important use categories. The 12 most common plant families in BFA differed considerably in their usefulness and application. Fabaceae, Poaceae and Malvaceae were the plant families with the most used species. In this study Khaya senegalensis, Adansonia digitata and Diospyros mespiliformis were ranked the top useful plants in BFA. Infections/Infestations, digestive system disorders and genitourinary disorders are the health problems most commonly addressed with medicinal plants. Fabaceae, Poaceae, Asteraceae, Apocynaceae, Malvaceae and Rubiaceae were the most important plant families in traditional medicine. Tamarindus indica, Vitellaria paradoxa and Adansonia digitata were ranked the most important medicinal plants. Conclusions: The national-scale analysis revealed systematic patterns of traditional plant use throughout BFA. These results are of interest for applied research, as a detailed knowledge of traditional plant use can a) help to communicate conservation needs and b) facilitate future research on drug screening.
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22.
  • Cano, A., et al. (författare)
  • Recent and local diversification of Central American understorey palms
  • 2022
  • Ingår i: Global Ecology and Biogeography. - : Wiley. - 1466-822X .- 1466-8238. ; 31:8, s. 1513-1525
  • Tidskriftsartikel (refereegranskat)abstract
    • Aim Central America is largely covered by hyperdiverse, yet poorly understood, rain forests. Understorey palms are diverse components of these forests, but little is known about their historical assembly. It is not clear when palms in Central America reached present diversity levels and whether most species arrived from neighbouring regions or evolved locally. We addressed these questions using the most species-rich American palm clades indicative of rain forests. We reconstructed and compared their phylogenomic and biogeographical history with the diversification of 54 other plant lineages, to gain a better understanding of the processes that shaped the assembly of Central American rain forests. Location Central America. Time period Cretaceous to present. Major taxa studied Arecaceae: Arecoideae: Bactridinae, Chamaedoreeae, Geonomateae. Methods We sampled 218 species through fieldwork and living collections. We sequenced their genomic DNA using target sequence-capture procedures. Using 12 calibration points, we reconstructed dated phylogenies under three approaches (multispecies coalescent, maximum likelihood and Bayesian inference), conducted biogeographical analyses (dispersal-extinction-cladogenesis) and estimated phylogenetic diversity metrics. Results Dated phylogenies revealed intense diversification in Central America from 12 Ma. Local diversification events were four times more frequent than dispersal events, and we found strong phylogenetic clustering in relationship to Central America. Main conclusions Our results suggest that most understorey palm species that characterize the Central American rain forests today evolved locally after repeated dispersal events, mostly from South America. Understorey palms in Central American rain forests diversified primarily after closure of the Central American Seaway at c. 13 Ma, suggesting that the Great American Biotic Interchange was a major trigger for plant diversification in Central American rain forests. This recent diversification contrasts with the much earlier existence of rain forest palms in neighbouring South America since c. 58 Ma. We found similar timings of diversification in 54 other seed plant lineages, suggesting an unexpectedly recent assembly of the hyperdiverse Central American flora.
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23.
  • Cruz, G. A. S., et al. (författare)
  • Molecular phylogeny, character evolution and historical biogeography of Cryptanthus Otto & A. Dietr. (Bromeliaceae)
  • 2017
  • Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903 .- 1095-9513. ; 107, s. 152-165
  • Tidskriftsartikel (refereegranskat)abstract
    • Cryptanthus comprises 72 species endemic to eastern Brazil with a center of diversity in the Atlantic Forest. The majority of the species are threatened due to habitat loss. We reconstructed phylogenetic relationships in Cryptanthus based on amplified fragment length polymorphisms (AFLP) including 48 species and 109 accessions. The Bayesian phylogenetic analysis revealed four major lineages in Cryptanthus and provided further evidence for the paraphyly of subgen. Hoplocryptanthus, while subgenus Cryptanthus was resolved as monophyletic. Monophyly of previously recognized morphological species groups at sectional level could not be confirmed. Based on the phylogenetic reconstruction we inferred the evolution of the sex system in Cryptanthus via maximum likelihood (ML) ancestral character reconstruction. Homoecy, the possession of hermaphrodite flowers only, was reconstructed as the ancestral state in the genus and characterizes three of the four main lineages within Cryptanthus. Andromonoecy, the possession of male and hermaphrodite flowers on the same plant, evolved only once and represents a synapomorphy of the fourth main lineage, C. subgen. Cryptanthus. The ancestral biome analysis reconstructed Cerrado (semiarid scrublands and forests) and campos rupestres (rock fields) as the most likely ancestral biomes for the genus. A shift to the Atlantic Forest biome was reconstructed to have occurred twice, in the ancestor of the first diverging lineage within the genus and in the ancestor of the C. subgen. Cryptanthus clade. A shift to the Caatinga (tropical dryland savanna) and one reversal to Cerrado (campos rupestres - rock fields) was reconstructed to have occurred once, in C. bahianus and C. arelii, respectively. The ancestral biome reconstruction indicates a high degree of niche conservatism within Cryptanthus with rare biome shifts throughout the evolution of the genus. Further, our results imply that the current infrageneric taxonomy of Cryptanthus is problematic and requires revision. © 2016 Elsevier Inc.
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24.
  • Guedes, Thaís, et al. (författare)
  • Patterns, biases and prospects in the distribution and diversity of Neotropical snakes
  • 2018
  • Ingår i: Global Ecology and Biogeography. - : Wiley. - 1466-822X .- 1466-8238. ; 27:1, s. 14-21
  • Tidskriftsartikel (refereegranskat)abstract
    • Motivation: We generated a novel database of Neotropical snakes (one of the world's richest herpetofauna) combining the most comprehensive, manually compiled distribution dataset with publicly available data. We assess, for the first time, the diversity patterns for all Neotropical snakes as well as sampling density and sampling biases. Main types of variables contained: We compiled three databases of species occurrences: a dataset downloaded from the Global Biodiversity Information Facility (GBIF), a verified dataset built through taxonomic work and specialized literature, and a combined dataset comprising a cleaned version of the GBIF dataset merged with the verified dataset. Spatial location and grain: Neotropics, Behrmann projection equivalent to 1 degrees x 1 degrees. Results: The combined dataset provides the most comprehensive distribution database for Neotropical snakes to date. It contains 147,515 records for 886 species across 12 families, representing 74% of all species of snakes, spanning 27 countries in the Americas. Species richness and phylogenetic diversity show overall similar patterns. Amazonia is the least sampled Neotropical region, whereas most well-sampled sites are located near large universities and scientific collections. We provide a list and updated maps of geographical distribution of all snake species surveyed. Main conclusions: The biodiversity metrics of Neotropical snakes reflect patterns previously documented for other vertebrates, suggesting that similar factors may determine the diversity of both ectothermic and endothermic animals. We suggest conservation strategies for high-diversity areas and sampling efforts be directed towards Amazonia and poorly known species.
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25.
  • Helmstetter, A. J., et al. (författare)
  • Unraveling the Phylogenomic Relationships of the Most Diverse African Palm Genus Raphia (Calamoideae, Arecaceae)
  • 2020
  • Ingår i: Plants-Basel. - : MDPI AG. - 2223-7747. ; 9:4
  • Tidskriftsartikel (refereegranskat)abstract
    • Palms are conspicuous floristic elements across the tropics. In continental Africa, even though there are less than 70 documented species, they are omnipresent across the tropical landscape. The genus Raphia has 20 accepted species in Africa and one species endemic to the Neotropics. It is the most economically important genus of African palms with most of its species producing food and construction material. Raphia is divided into five sections based on inflorescence morphology. Nevertheless, the taxonomy of Raphia is problematic with no intra-generic phylogenetic study available. We present a phylogenetic study of the genus using a targeted exon capture approach sequencing of 56 individuals representing 18 out of the 21 species. Our results recovered five well supported clades within the genus. Three sections correspond to those based on inflorescence morphology. R. regalis is strongly supported as sister to all other Raphia species and is placed into a newly described section: Erectae. Overall, morphological based identifications agreed well with our phylogenetic analyses, with 12 species recovered as monophyletic based on our sampling. Species delimitation analyses recovered 17 or 23 species depending on the confidence level used. Species delimitation is especially problematic in the Raphiate and Temulentae sections. In addition, our clustering analysis using SNP data suggested that individual clusters matched geographic distribution. The Neotropical species R. taedigera is supported as a distinct species, rejecting the hypothesis of a recent introduction into South America. Our analyses support the hypothesis that the Raphia individuals from Madagascar are potentially a distinct species different from the widely distributed R. farinifera. In conclusion, our results support the infra generic classification of Raphia based on inflorescence morphology, which is shown to be phylogenetically useful. Classification and species delimitation within sections remains problematic even with our phylogenomic approach. Certain widely distributed species could potentially contain cryptic species. More in-depth studies should be undertaken using morphometrics, increased sampling, and more variable markers. Our study provides a robust phylogenomic framework that enables further investigation on the biogeographic history, morphological evolution, and other eco-evolutionary aspects of this charismatic, socially, and economically important palm genus.
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26.
  • Klimes, A., et al. (författare)
  • The ecological drivers of growth form evolution in flowering plants
  • 2022
  • Ingår i: Journal of Ecology. - : Wiley. - 0022-0477 .- 1365-2745. ; 10:7, s. 1525-36
  • Tidskriftsartikel (refereegranskat)abstract
    • In flowering plants (angiosperms), the herbaceous habit has evolved repeatedly from the ancestral woody state and herbs evolved repeatedly back to woody plants. Yet, how common these transitions were and which ecological conditions promote the herbaceous habit is poorly known. Several hypotheses exist, postulating an advantage of the herbaceous growth form to better cope with frost, drought, fire and shade and in allowing a fast life strategy, but their evaluation has been hitherto limited and support equivocal. We aim to evaluate these hypotheses by testing the difference between woody plants and herbs for a set of variables related to these hypotheses. We compiled and integrated data for up to 21,581 species representing 359 families from public databases. We estimated the minimum number of evolutionary transitions between both growth forms. We assembled data on frost, drought, fire and shade tolerances, clonality and specific leaf area and we tested individual hypotheses by comparing herbaceous and woody angiosperm growth forms globally and within selected biomes and clades using phylogenetic comparative analyses. We found 1656 evolutionary transitions from woody towards herbaceous growth form and 2111 transitions in the opposite direction. In agreement with our expectations, herbs were more tolerant to frost and shade than woody plants and had higher specific leaf area. However, the growth forms did not differ in their fire tolerance and clonality. Furthermore, contrary to our expectation, woody plants were more drought tolerant than herbs. The majority of the differences were robust to the choice of biome or clade. Synthesis. Both herbaceous and woody habits evolved many times making the evolution of growth forms a well-replicated event and suggesting that conditions favourable for either of the growth forms emerge often and plants respond to them. Apart from standard explanation by low temperatures, the success of herbs was likely enabled also by biotic interactions-by their fast life strategy, which is beneficial in seasonal and early successional habitats, and by their ability to tolerate shade.
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27.
  • Pimiento, C., et al. (författare)
  • Selective extinction against redundant species buffers functional diversity
  • 2020
  • Ingår i: Proceedings of the Royal Society B-Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 287:1931
  • Tidskriftsartikel (refereegranskat)abstract
    • The extinction of species can destabilize ecological processes. A way to assess the ecological consequences of species loss is by examining changes in functional diversity. The preservation of functional diversity depends on the range of ecological roles performed by species, or functional richness, and the number of species per role, or functional redundancy. However, current knowledge is based on short timescales and an understanding of how functional diversity responds to long-term biodiversity dynamics has been limited by the availability of deep-time, trait-based data. Here, we compile an exceptional trait dataset of fossil molluscs from a 23-million-year interval in the Caribbean Sea (34 011 records, 4422 species) and develop a novel Bayesian model of multi-trait-dependent diversification to reconstruct mollusc (i) diversity dynamics, (ii) changes in functional diversity, and (iii) extinction selectivity over the last 23 Myr. Our results identify high diversification between 23-5 Mya, leading to increases in both functional richness and redundancy. Conversely, over the last three million years, a period of high extinction rates resulted in the loss of 49% of species but only 3% of functional richness. Extinction rates were significantly higher in small, functionally redundant species suggesting that competition mediated the response of species to environmental change. Taken together, our results identify long-term diversification and selective extinction against redundant species that allowed functional diversity to grow over time, ultimately buffering the ecological functions of biological communities against extinction.
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28.
  • Andermann, Tobias, et al. (författare)
  • SECAPR-a bioinformatics pipeline for the rapid and user-friendly processing of targeted enriched Illumina sequences, from raw reads to alignments
  • 2018
  • Ingår i: Peerj. - : PeerJ. - 2167-8359. ; 6
  • Tidskriftsartikel (refereegranskat)abstract
    • Evolutionary biology has entered an era of unprecedented amounts of DNA sequence data, as new sequencing technologies such as Massive Parallel Sequencing (MPS) can generate billions of nucleotides within less than a day. The current bottleneck is how to efficiently handle, process, and analyze such large amounts of data in an automated and reproducible way. To tackle these challenges we introduce the Sequence Capture Processor (SECAPR) pipeline for processing raw sequencing data into multiple sequence alignments for downstream phylogenetic and phylogeographic analyses. SECAPR is user-friendly and we provide an exhaustive empirical data tutorial intended for users with no prior experience with analyzing MPS output. SECAPR is particularly useful for the processing of sequence capture (synonyms: target or hybrid enrichment) datasets for non-model organisms, as we demonstrate using an empirical sequence capture dataset of the palm genus Geonoma (Arecaceae). Various quality control and plotting functions help the user to decide on the most suitable settings for even challenging datasets. SECAPR is an easy-to-use, free, and versatile pipeline, aimed to enable efficient and reproducible processing of MPS data for many samples in parallel.
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29.
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30.
  • Carrillo, Juan D., et al. (författare)
  • Disproportionate extinction of South American mammals drove the asymmetry of the Great American Biotic Interchange
  • 2020
  • Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424. ; 117:42, s. 26281-26287
  • Tidskriftsartikel (refereegranskat)abstract
    • The interchange between the previously disconnected faunas of North and South America was a massive experiment in biological invasion. A major gap in our understanding of this invasion is why there was a drastic increase in the proportion of mammals of North American origin found in South America. Four nonmutually exclusive mechanisms may explain this asymmetry: 1) Higher dispersal rate of North American mammals toward the south, 2) higher origination of North American immigrants in South America, 3) higher extinction of mammals with South American origin, and 4) similar dispersal rate but a larger pool of native taxa in North versus South America. We test among these mechanisms by analyzing similar to 20,000 fossil occurrences with Bayesian methods to infer dispersal and diversification rates and taxonomic selectivity of immigrants. We find no differences in the dispersal and origination rates of immigrants. In contrast, native South American mammals show higher extinction. We also find that two clades with North American origin (Carnivora and Artiodactyla) had significantly more immigrants in South America than other clades. Altogether, the asymmetry of the interchange was not due to higher origination of immigrants in South America as previously suggested, but resulted from higher extinction of native taxa in southern South America. These results from one of the greatest biological invasions highlight how biogeographic processes and biotic interactions can shape continental diversity.
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31.
  • Ryska, P., et al. (författare)
  • Variability of Normal Pressure Hydrocephalus Imaging Biomarkers with Respect to Section Plane Angulation : How Wrong a Radiologist Can Be?
  • 2021
  • Ingår i: American Journal of Neuroradiology. - : American Society of Neuroradiology. - 0195-6108 .- 1936-959X. ; 42:7, s. 1201-1207
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND AND PURPOSE: Systematic analysis of angulation-related variability of idiopathic normal pressure hydrocephalus imaging biomarkers has not been published yet. Our aim was to evaluate the variability of these radiologic biomarkers with respect to imaging plane angulation.MATERIALS AND METHODS: Eighty subjects (35 with clinically confirmed idiopathic normal pressure hydrocephalus and 45 age- and sex-matched healthy controls) were prospectively enrolled in a 3T brain MR imaging study. Two independent readers assessed 12 radiologic idiopathic normal pressure hydrocephalus biomarkers on sections aligned parallel or perpendicular to the bicallosal, bicommissural, hypophysis-fastigium, and brain stem vertical lines, respectively.RESULTS: Disproportionately enlarged subarachnoid space hydrocephalus, simplified callosal angle, frontal horn diameter, z-Evans Index, and cella media vertical width did not show significant systematic differences in any of 6 section plane combinations studied. The remaining 7 biomarkers (including the Evans Index and callosal angle) showed significant differences in up to 4 of 6 mutually compared section plane combinations. The values obtained from sections aligned with the brain stem vertical line (parallel to the posterior brain stem margin) showed the most deviating results from other section angulations.CONCLUSIONS: Seven of 12 idiopathic normal pressure hydrocephalus biomarkers including the frequently used Evans Index and callosal angle showed statistically significant deviations when measured on sections whose angulations differed or did not comply with the proper section definition published in the original literature. Strict adherence to the methodology of idiopathic normal pressure hydrocephalus biomarker assessment is, therefore, essential to avoid an incorrect diagnosis. Increased radiologic and clinical attention should be paid to the biomarkers showing low angulation-related variability yet high specificity for idiopathic normal pressure hydrocephalus-related morphologic changes such as the z-Evans Index, frontal horn diameter, or disproportionately enlarged subarachnoid space hydrocephalus.
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32.
  • Schneider, J. V., et al. (författare)
  • Phylogenomics of the tropical plant family Ochnaceae using targeted enrichment of nuclear genes and 250+taxa
  • 2021
  • Ingår i: Taxon. - : Wiley. - 0040-0262 .- 1996-8175. ; 70:1, s. 48-71
  • Tidskriftsartikel (refereegranskat)abstract
    • Targeted capture of nuclear genes increasingly contributes to unravelling phylogenetic relationships that hitherto remained unresolved because of limitations of traditional Sanger sequencing. In particular, the study of tropical plant families has been compromised because they often rely on highly degraded DNA obtained from herbarium specimens. One such example is the pantropical Ochnaceae, which comprises 33 genera and approximately 550 species, occurring mostly in savannas and moist tropical forests. Here, we developed a set of baits covering about 660,000 bp from 275 nuclear genes used for the targeted enrichment based on all but one genus and more than 250 species. Using this novel dataset, we resolved the phylogenetic backbone of Ochnaceae, including that of Ochninae, and we established new relationships. Most importantly, our findings highlight that the neotropical and palaeotropical taxa of Sauvagesia form independent clades, requiring the re-erection of formerly separate genera. Ouratea and Ochna (both Ochninae), by far the most species-rich genera and represented by 120 and 41 species, respectively, came out as monophyletic. In contrast, the third-most species-rich genus, Campylospermum, is polyphyletic in two distinct clades. Ouratea, the only neotropical genus of Ochninae, was sister to the five palaeotropical genera of this subtribe. The bait kit developed in this study proved to be particularly useful for unravelling relationships within Ochninae, which includes about two-thirds of the species diversity in the family.
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33.
  • Silva, S. V., et al. (författare)
  • Global Estimation and Mapping of the Conservation Status of Tree Species Using Artificial Intelligence
  • 2022
  • Ingår i: Frontiers in Plant Science. - : Frontiers Media SA. - 1664-462X. ; 13
  • Tidskriftsartikel (refereegranskat)abstract
    • Trees are fundamental for Earth's biodiversity as primary producers and ecosystem engineers and are responsible for many of nature's contributions to people. Yet, many tree species at present are threatened with extinction by human activities. Accurate identification of threatened tree species is necessary to quantify the current biodiversity crisis and to prioritize conservation efforts. However, the most comprehensive dataset of tree species extinction risk-the Red List of the International Union for the Conservation of Nature (IUCN RL)-lacks assessments for a substantial number of known tree species. The RL is based on a time-consuming expert-based assessment process, which hampers the inclusion of less-known species and the continued updating of extinction risk assessments. In this study, we used a computational pipeline to approximate RL extinction risk assessments for more than 21,000 tree species (leading to an overall assessment of 89% of all known tree species) using a supervised learning approach trained based on available IUCN RL assessments. We harvested the occurrence data for tree species worldwide from online databases, which we used with other publicly available data to design features characterizing the species' geographic range, biome and climatic affinities, and exposure to human footprint. We trained deep neural network models to predict their conservation status, based on these features. We estimated 43% of the assessed tree species to be threatened with extinction and found taxonomic and geographic heterogeneities in the distribution of threatened species. The results are consistent with the recent estimates by the Global Tree Assessment initiative, indicating that our approach provides robust and time-efficient approximations of species' IUCN RL extinction risk assessments.
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34.
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35.
  • Zizka, A., et al. (författare)
  • Automated conservation assessment of the orchid family with deep learning
  • 2021
  • Ingår i: Conservation Biology. - : Wiley. - 0888-8892 .- 1523-1739. ; 35:3, s. 897-908
  • Tidskriftsartikel (refereegranskat)abstract
    • International Union for Conservation of Nature (IUCN) Red List assessments are essential for prioritizing conservation needs but are resource intensive and therefore available only for a fraction of global species richness. Automated conservation assessments based on digitally available geographic occurrence records can be a rapid alternative, but it is unclear how reliable these assessments are. We conducted automated conservation assessments for 13,910 species (47.3% of the known species in the family) of the diverse and globally distributed orchid family (Orchidaceae), for which most species (13,049) were previously unassessed by IUCN. We used a novel method based on a deep neural network (IUC-NN). We identified 4,342 orchid species (31.2% of the evaluated species) as possibly threatened with extinction (equivalent to IUCN categories critically endangered [CR], endangered [EN], or vulnerable [VU]) and Madagascar, East Africa, Southeast Asia, and several oceanic islands as priority areas for orchid conservation. Orchidaceae provided a model with which to test the sensitivity of automated assessment methods to problems with data availability, data quality, and geographic sampling bias. The IUC-NN identified possibly threatened species with an accuracy of 84.3%, with significantly lower geographic evaluation bias relative to the IUCN Red List and was robust even when data availability was low and there were geographic errors in the input data. Overall, our results demonstrate that automated assessments have an important role to play in identifying species at the greatest risk of extinction.
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36.
  • Zizka, A., et al. (författare)
  • Bio-Dem, a tool to explore the relationship between biodiversity data availability and socio-political conditions in time and space
  • 2021
  • Ingår i: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 48:11, s. 2715-2726
  • Tidskriftsartikel (refereegranskat)abstract
    • Aim Geo-referenced species occurrence records are a prime example of biodiversity data and a cornerstone of biodiversity research. Yet, their availability depends on non-biological factors, including the political framework in the region of collection. Here we present Bio-Dem (), an open-source software to explore the relationship between the availability of species occurrence records and the political framework in countries worldwide and through time. Location Global. Taxon Any. Methods Bio-Dem accesses the number of occurrence records available from countries worldwide from the Global Biodiversity Information Facility () and socio-political information from these countries from the Varieties of Democracy database () as well as information on colonial history from the Issue Correlates of War Project. Results Bio-Dem is available as a free graphical user interface web application at . Through three interactive graphs, Bio-Dem enables users to explore the relationship between species occurrence records and countries' regime type, freedom of movement, freedom of association, gross domestic product, education length, political corruption, armed conflict and colonial history. We describe possible links of these specific political indicators with the collection and mobilization of biodiversity data. Illustrative examples and video tutorials explaining the use of Bio-Dem are available at . Main conclusions Bio-Dem provides a user-friendly way to explore the link between socio-political variables and the availability of species occurrence records in user-selected taxa and geographic regions, and to generate hypotheses on their connection. We envision Bio-Dem as a useful tool for teachers communicating the caveats of available biodiversity data, for biodiversity scientists exploring potential spatial and temporal bias in their data, and for social scientists exploring the impact of political systems on scientific data collection and biodiversity conservation.
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37.
  • Zizka, A., et al. (författare)
  • IUCNN - Deep learning approaches to approximate species' extinction risk
  • 2022
  • Ingår i: Diversity and Distributions. - : Wiley. - 1366-9516 .- 1472-4642. ; 28:2
  • Tidskriftsartikel (refereegranskat)abstract
    • Aim: The Red List (RL) from the International Union for the Conservation of Nature is the most comprehensive global quantification of extinction risk, and widely used in applied conservation as well as in biogeographic and ecological research. Yet, due to the time-consuming assessment process, the RL is biased taxonomically and geographically, which limits its application on large scales, in particular for underdocumented areas such as the tropics, or understudied taxa, such as most plants and invertebrates. Here, we present IUCNN, an R-package implementing deep learning models to predict species RL status from publicly available geographic occurrence records (and other data if available). Innovation: We implement a user-friendly workflow to train and validate neural network models, and use them to predict species RL status. IUCNN contains specific functions for extinction risk prediction in the RL framework, including a regression-based approach to account for the ordinal nature of RL categories, a Bayesian approach for improved uncertainty quantification and a convolutional neural network to predict species RL status based on their raw geographic occurrences. Most analyses run with few lines of code, not requiring users to have prior experience with neural network models. We demonstrate the use of IUCNN on an empirical dataset of similar to 14,000 orchid species, for which IUCNN models can predict extinction risk within minutes, while outperforming comparable methods based on species occurrence information. Main conclusions: IUCNN harnesses innovative methodology to estimate the RL status of large numbers of species. By providing estimates of the number and identity of threatened species in custom geographic or taxonomic datasets, IUCNN enables large-scale automated assessments of the extinction risk of species so far not well represented on the official RL.
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38.
  • Zizka, A., et al. (författare)
  • sampbias, a method for quantifying geographic sampling biases in species distribution data
  • 2021
  • Ingår i: Ecography. - : Wiley. - 0906-7590 .- 1600-0587. ; 44:1, s. 25-32
  • Tidskriftsartikel (refereegranskat)abstract
    • Geo-referenced species occurrences from public databases have become essential to biodiversity research and conservation. However, geographical biases are widely recognized as a factor limiting the usefulness of such data for understanding species diversity and distribution. In particular, differences in sampling intensity across a landscape due to differences in human accessibility are ubiquitous but may differ in strength among taxonomic groups and data sets. Although several factors have been described to influence human access (such as presence of roads, rivers, airports and cities), quantifying their specific and combined effects on recorded occurrence data remains challenging. Here we present sampbias, an algorithm and software for quantifying the effect of accessibility biases in species occurrence data sets. sampbias uses a Bayesian approach to estimate how sampling rates vary as a function of proximity to one or multiple bias factors. The results are comparable among bias factors and data sets. We demonstrate the use of sampbias on a data set of mammal occurrences from the island of Borneo, showing a high biasing effect of cities and a moderate effect of roads and airports. sampbias is implemented as a well-documented, open-access and user-friendly R package that we hope will become a standard tool for anyone working with species occurrences in ecology, evolution, conservation and related fields. © 2020 The Authors. Ecography published by John Wiley & Sons Ltd on behalf of Nordic Society Oikos
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39.
  • Zizka, Alexander, 1986, et al. (författare)
  • Transitions between biomes are common and directional in Bombacoideae (Malvaceae)
  • 2020
  • Ingår i: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 47:6, s. 1310-1321
  • Tidskriftsartikel (refereegranskat)abstract
    • Aim To quantify evolutionary transitions between tropical evergreen rain forest and seasonally dry biomes, to test whether biome transitions affect lineage diversification and to examine the robustness of these results to methodological choices. Location The tropics. Time period The Cenozoic. Major taxa studied The plant subfamily Bombacoideae (Malvaceae). Methods We inferred ancestral biomes based on a fossil-dated molecular phylogeny of 103 species (59% of the clade) and recorded the number of transitions among biomes using biogeographical stochastic mapping based on the dispersal-extinction-cladogenesis model. We then estimated diversification rates using state-specific speciation and extinction rate (SSE) methods. Furthermore, we tested the sensitivity of the results to model choice, phylogenetic uncertainty, measurement error and biome definition. Results We found numerous transitions from evergreen rain forest to seasonally dry biomes, and fewer in the opposite direction. These results were robust to methodological choices. Biome type did not influence diversification rates, although this result was subject to uncertainty, especially related to model choice and biome definition. Main conclusions Our results contradict the idea of evolutionary biome conservatism in Bombacoideae, and support previous findings that evergreen rain forests serve as a source for the flora of seasonally dry biomes. The impact of biome classification and biome definition on the results suggest caution when using a biome concept for biogeographical reconstruction and diversification rate analysis.
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