Ian Donald Cowie

Some plant lineages remain within the same biome over time (biome conservatism), whereas others seem to adapt more easily to new biomes. The c. 398 species (14 genera) of subfamily Cercidoideae (Leguminosae or Fabaceae) are found in many biomes around the world, particularly in the tropical regions of South America, Asia and Africa, and display a variety of growth forms (small trees, shrubs, lianas and herbaceous perennials). Species distribution maps derived from cleaned occurrence records were compiled and compared with existing biome maps and with the literature to assign species to biomes. Rainforest (144 species), succulent (44 species), savanna (36 species), and temperate (10 species) biomes were found to be important in describing the global distribution of Cercidoideae, with many species occurring in more than one biome. Two phylogenetically isolated species-poor temperate ( Cercis ) and succulent ( Adenolobus ) biome lineages are sister to two broadly distributed species-rich tropical clades. Ancestral state reconstructions on a time-calibrated phylogeny suggest biome shifts occurred throughout the evolutionary history of the subfamily, with shifts between the succulent and rainforest biomes, from the rainforest to savanna, from the succulent to savanna biome, and one early occurring shift into (or from) the temperate biome. Of the 26 inferred shifts in biome, three are closely associated with a shift from the ancestral tree/shrub growth form to a liana or herbaceous perennial habit. Only three of the 13 inferred transcontinental dispersal events are associated with biome shifts. Overall, we find that biome shifts tend to occur within the same continent and that dispersals to new continents tend to occur within the same biome, but that nonetheless the biome-conserved and biogeographically structured Cercidoideae have been able to adapt to different environments through time.

Herbarium specimens provide an important and central resource for biodiversity research. Making these records digitally available to end-users represents numerous challenges, in particular, transcribing metadata associated with specimen labels. In this study, we used the citizen science initiative ‘Les Herbonautes’ and the Récolnat network to transcribe specific data from all herbarium specimen labels stored at the Muséum national d’Histoire naturelle in Paris of the large tropical plant family Annonaceae. We compared this database with publicly available global biodiversity repository data and expert checklists. We investigated spatial and taxonomic advances in data availability at the global and country scales. A total of 20 738 specimens were transcribed over the course of more than two years contributing to and significantly extending the previously available specimen and species data for Annonaceae worldwide. We show that several regions, mainly in Africa and South East Asia not covered by online global datasets, are uniquely available in the P herbarium, probably linked to past history of the museum’s botanical exploration. While acknowledging the challenges faced during the transcription of historic specimens by citizen scientists, this study highlights the positive impact of adding records to global datasets both in space and time. This is illustrative for researchers, collection managers, policy makers as well as funders. These datasets will be valuable for numerous future studies in biodiversity research, including ecology, evolution, conservation and climate change science.

Invasive sandburs (Cenchrus spp.), tropical and subtropical plants, are preferred in grasslands and agricultural ecosystems worldwide, causing significant crop production losses and reducing native biodiversity. Integrating phylogenetic relatedness and potentially suitable habitats (PSHs) to identify areas at risk of invasion is critical for prioritizing management efforts and supporting decisions on early warning and surveillance for sandbur invasions. However, despite risk assessments for individual Cenchrus species, the combined analysis of suitable habitats and phylogenetic relationships remains unclear. Therefore, this study aims to assess the invasion risk regions—including PSHs, species richness (SR), and phylogenetic structure—of eight invasive and potentially invasive sandburs in China, to quantify their niche overlap and identify driving factors. Our results showed that the phylogenetic distance of potentially invasive sandburs was closely related to invasive sandburs. Especially, three potentially invasive sandburs, C. ciliaris, C. setigerus, and C. myosuroides, possessed invasion potential resulting from close phylogenetic relatedness and high climatic suitability compared with invasive sandburs. The PSHs for invasive sandburs were distributed in wider regions except northwest China and had higher suitability to different environmental conditions. Potentially invasive sandburs were primarily located in southwestern and southern China driven by precipitation, especially, being inspected in Guangdong, Hainan, and Yunnan on numerous occasions, or potentially introduced in Guangxi, Taiwan, and Fujian for sandburs invasion hotspots. The phylogenetic clustering for eight sandburs occurred in the eastern, center, and southern coastal China, where higher SR in distribution was correlated with invasion hotspots. The SR and phylogenetic relatedness metrics were related to temperature and topographic variables. Totally, the expansion and invasion risk could be increased toward higher latitudes under future global warming. These findings offer novel insights for the prevention and management of sandburs invasions.

AbstractPremiseThe ecological conditions that constrain plants to an environmental niche are assumed to be constant through time. While the fossil record has been used previously to test for niche conservatism of woody flowering plants, additional studies are needed in other plant groups especially since they can provide insight with paleoclimatic reconstructions, high biodiversity in modern terrestrial ecosystems, and significant contributions to agriculture.MethodsWe tested climatic niche conservatism across time by characterizing the climatic niches of living herbaceous ginger plants (Zingiberaceae) and woody dawn redwood (Metasequoia) against paleoniches reconstructed based on fossil distribution data and paleoclimatic models.ResultsDespite few fossil Zingiberaceae occurrences in the latitudinal tropics, unlike living Zingiberaceae, extinct Zingiberaceae likely experienced paratropical conditions in the higher latitudes, especially in the Cretaceous and Paleogene. The living and fossil distributions of Metasequoia largely remain in the upper latitudes of the northern hemisphere. The Zingiberaceae shifted from an initial subtropical climatic paleoniche in the Cretaceous, toward a temperate regime in the late Cenozoic; Metasequoia occupied a more consistent climatic niche over the same time intervals.ConclusionsBecause of the inconsistent climatic niches of Zingiberaceae over geologic time, we are less confident of using them for taxonomic‐based paleoclimatic reconstruction methods like nearest living relative, which assume a consistent climatic niche between extant and extinct relatives; we argue that the consistent climatic niche of Metasequoia is more appropriate for these reconstructions. Niche conservatism cannot be assumed between extant and extinct plants and should be tested further in groups used for paleoclimatic reconstructions.

ABSTRACTAimFerns are globally distributed, yet the number of studies examining the historical evolution of African taxa is relatively low. Investigation of the evolution of African fern diversity is critical in order to understand patterns and processes that have global relevance (e.g., the pantropical diversity disparity [PDD] pattern). This study aims to examine when and from where a globally distributed fern lineage arrived in sub‐Saharan Africa, to obtain a better understanding of potential processes contributing to patterns of diversity across the region.LocationGlobal, sub‐Saharan Africa.TaxonAsplenium (Aspleniaceae).MethodsWe analysed five loci from 537 Asplenium taxa using a maximum likelihood (IQ‐Tree) phylogenetic framework. For age estimation, we performed penalised likelihood as implemented in treePL, and executed a Bayesian analysis using BEAST. Biogeographical analyses were carried out using BioGeoBEARS.ResultsMost dispersals into Africa occurred within the last ~55 myr, with the highest diversity of sub‐Saharan African taxa concentrated in two clades, each of which descended from an Asian ancestor. Additional dispersals to sub‐Saharan Africa can be found throughout the phylogeny. Lastly, potential cryptic species diversity exists within Asplenium as evidenced by several polyphyletic taxa.Main ConclusionsWe recover multiple dispersals of Asplenium to sub‐Saharan Africa, with two major lineages likely diversifying after arrival.

Considering the global biodiversity crisis and the growing demand for medicinal plants, it is crucial to preserve therapeutically useful herbs. From a conservation management perspective under climate change, identifying areas that enable valuable natural resources to persist in the future is crucial. Machine learning-based models are commonly used to estimate the locations of climate refugia, which are critical for the effective species conservation. The aim of this study was to assess the impact of global warming on the epiphytic medicinal orchid— Bulbophyllum odoratissimum. Given how the long-term survival of plants inhabiting shrubs and trees depends on the availability of suitable phorophyets, in this research potential range changes in reported orchid plant hosts were evaluated. According to conducted analyses, global warming will cause a decline in the coverage of the suitable niches for B. odoratissimum and its main phorophyte. The most significant habitat loss in the case of the studied orchid and Pistacia weinmannifolia will be observed in the southern part of their geographical ranges and some new niches will simultaneously become available for these plants in the northern part. Climate change will significantly increase the overlap of geographical ranges of P. weinmannifolia and the orchid. In the SSP5-8.5 scenario trees will be available for more than 56% of the orchid population. Other analyzed phorophytes, will be available for B. odoratissimum to a very reduced extent, as orchids will only utilize these species as habitats only occasionally. This study provides data on the distribution of climatic refugia of B. odoratissimum under global warming. Moreover, this is the first evaluation of the future geographical ranges for its phorophytes. According to the conducted analyses, only one of the previously reported tree species which are inhabited by B. odoratissimum , P. weinmannifolia, can serve as a phorophyte for this orchid in the future. In this study, the areas designated as suitable for the occurrence of both orchids and their phorophytes should be considered priority conservation areas for the studied medicinal plants.

Traits associated with successful biological invasions across environmental gradients or geographical distances may vary depending on processes such as founder effects, ecological sorting, or adaptation to local conditions. Consequently, drivers of success are not necessarily consistent throughout the invasive range. We evaluate how plant traits, reproductive success and climatic preferences vary in populations of a naturalized orchid on islands in the Atlantic, Pacific and Indian oceans. Populations of Arundina graminifolia (bamboo orchid) were located on Puerto Rico, Hawaiian Islands (Hawai’i, O’ahu, Kaua’i), and Mauritius. Vegetative and reproductive traits were measured, and male and female success were assessed. Populations were compared using multivariate approaches. Species distribution modeling was used to assess potential climatic preferences within and among islands. Floral morphology differed among islands but considerable overlap in trait distributions exists. Reproductive success significantly differed among islands and was linked to floral traits, local pollinator pools and perhaps variable levels of florivory. Hawaiian populations occupied the broadest climatic niche space and Mauritius the most restricted. The effectiveness of using present points from the native range to reveal climatic suitability on invaded islands varied among islands. Successful invasions across a broad geographical range can occur even when morphology, reproductive success and climatic conditions are variable. As expected, some aspects of this global invasion are similar, but others differ among islands underscoring the context dependency of biological invasions and the difficulty of overall predictions. Los rasgos asociados a las invasiones biológicas exitosas a través de gradientes ambientales o distancias geográficas pueden variar dependiendo de procesos tales como el efecto fundador, el sorteo ecológico, o las adaptaciones a las condiciones locales. Consecuentemente, los impulsores del éxito no son necesariamente consistentes a través de la distribución invadida. Nosotros evaluamos cómo los rasgos, el éxito reproductivo y las preferencias climáticas varían en poblaciones de una orquídea naturalizada en islas de los océanos Atlántico, Pacífico e Índico. Las poblaciones de Arundina graminifolia (orquídea bambú) estaban localizadas en Puerto Rico, las Islas Hawaianas (Hawai’i, O’ahu, Kaua’i) y en la Isla de Mauricio. Los rasgos vegetativos y reproductivos fueron medidos, y el éxito reproductivo masculino y femenino fue evaluado. Comparamos las poblaciones usando enfoques estadísticos multivariados. También usamos modelos de distribución de especies para evaluar las preferencias climáticas tanto dentro de las islas, así como entre ellas. La morfología floral difirió entre islas, pero existe un sobrelapamiento considerable en la distribución de rasgos. El éxito reproductivo fue significativamente diferente entre islas, y estuvo ligado a los rasgos florales, el conjunto de polinizadores locales y, quizá, a niveles variables de florivoría. Las poblaciones hawaianas ocuparon el nicho climático más amplio mientras que las mauricianas ocuparon el más restringido. La efectividad de usar puntos de presencia de la distribución nativa para revelar la adecuación climática de las islas invadidas varió entre islas. Encontramos que las invasiones exitosas a través de una distribución geográfica amplia pueden ocurrir a pesar de la variabilidad en morfología, éxito reproductivo y condiciones climáticas. Como era de esperarse, algunos aspectos de esta invasión global son similares, pero otros difieren entre islas, haciendo hincapié en la dependencia del contexto de las invasiones biológicas y la dificultad de hacer predicciones generalizadas. Les traits associés aux invasions biologiques sur des gradients environnementaux ou des distances géographiques peuvent varier en fonction de processus tels que les effets fondateurs, le tri écologique ou l'adaptation aux conditions locales. Par conséquent, les facteurs de réussite ne sont pas nécessairement cohérents dans l'ensemble de l'aire de répartition de l'invasion. Nous évaluons comment les caractéristiques des plantes, le succès de la reproduction et les préférences climatiques varient dans les populations d'une orchidée naturalisée sur des îles des océans Atlantique, Pacifique et Indien. Les populations d'Arundina graminifolia (orchidée bambou) ont été localisées à Porto Rico, dans les îles hawaïennes (Hawai'i, O'ahu, Kaua'i) et à l'île Maurice. Les traits végétatifs et reproductifs ont été mesurés, et le succès reproductifs des mâles et des femelles a été évalué. Les populations ont été comparées à l'aide d'approches multivariées. La modélisation de la distribution des espèces a été utilisée pour évaluer les préférences climatiques potentielles au sein des îles et entre elles. La morphologie florale diffère d'une île à l'autre, mais il existe un chevauchement considérable dans la répartition des caractéristiques. Le succès de la reproduction diffère significativement entre les îles et est lié aux caractéristiques florales, aux réservoirs locaux de pollinisateurs et peut-être à des niveaux variables de florivorie. Les populations hawaïennes ont occupé la niche climatique la plus large et les populations mauriciennes la plus restreinte. L'efficacité de l'utilisation de points de présences dans l'aire de répartition indigène pour révéler l'adéquation climatique des îles envahies varie d'une île à l'autre. Des invasions réussies sur une vaste aire de répartition géographique peuvent se produire même lorsque la morphologie, le succès de la reproduction et les conditions climatiques sont variables. Comme prévu, certains aspects de cette invasion mondiale sont similaires, mais d'autres diffèrent d'une île à l'autre, ce qui souligne l’importance du contexte des invasions biologiques et la difficulté des prédictions globales.

Centella asiatica is a medicinal plant recognized for its various benefits contributed by its metabolites and has been used as a food supplement since prehistorical times across various cultures. Due to the reliance on natural populations of C. asiatica and the impacts of environmental factors on its yield and centelloside production, there is a need to identify suitable cultivation areas for this species. We employed ecological niche modelling with bioclimatic and soil variables to evaluate the suitability of cultivation under current and future climatic scenarios. Our results identified suitable areas for cultivating C. asiatica worldwide, indicating its potential for global commercial cultivation. However, the niche reconstruction of highly concentrated centelloside was restricted to South and Southeast Asia due to the lack of available data. When we projected the modelled niche of centelloside in these regions, we observed a lower occurrence probability in some areas, suggesting potential challenges in cost-effectiveness. Nevertheless, our results suggest a consistent future distribution for this species when we projected the modelled niche under future climates based on various socio-economic scenarios. This study not only identifies suitable areas to develop commercial cultivation for C. asiatica with highly concentrated centelloside, but also provides supporting evidence of the consistency of these areas, which can increase its sustainability.

Premise Cleomaceae is an important model clade for studies of evolutionary processes including genome evolution, floral form diversification, and photosynthetic pathway evolution. Diversification and divergence patterns in Cleomaceae remain tangled as research has been restricted by its worldwide distribution, limited genetic sampling and species coverage, and a lack of definitive fossil calibration points.MethodsWe used target sequence capture and the Angiosperms353 probe set to perform a phylogenetic study of Cleomaceae. We estimated divergence times and biogeographic analyses to explore the origin and diversification of the family. Seed morphology across extant taxa was documented with multifocal image‐stacking techniques and morphological characters were extracted, analyzed, and compared to fossil records.ResultsWe recovered a well‐supported and resolved phylogenetic tree of Cleomaceae generic relationships that includes 236 (~86%) species. We identified 11 principal clades and confidently placed Cleomella as sister to the rest of the family. Our analyses suggested that Cleomaceae and Brassicaceae diverged ~56 mya, and Cleomaceae began to diversify ~53 mya in the Palearctic and Africa. Multiple transatlantic disjunct distributions were identified. Seeds were imaged from 218 (~80%) species in the family and compared to all known fossil species.ConclusionsOur results represent the most comprehensive phylogenetic study of Cleomaceae to date. We identified transatlantic disjunctions and proposed explanations for these patterns, most likely either long‐distance dispersals or contractions in latitudinal distributions caused by climate change over geological timescales. We found that seed morphology varied considerably but mostly mirrored generic relationships.

Submerged macrophytes remediation is a commonly used technique for improving water quality and restoring habitat in aquatic ecosystems. However, the drivers of success in the submerged macrophytes assembly process and their specific impacts on methane emissions are poorly understood. Thus, we conducted a mesocosm experiment to test the growth plasticity and carbon fixation of widespread submerged macrophytes (Vallisneria natans) under different nutrient conditions. A refined dynamic chamber method was utilized to concurrently collect and quantify methane emission fluxes arising from ebullition and diffusion processes. Significant correlations were found between methane flux and variations in the physiological activities of V. nantas by the fluorescence imaging system. Our results show that exceeding tolerance thresholds of ammonia in the water significantly interfered with the photosynthetic systems in submerged leaves and the radial oxygen loss in adventitious roots. The recovery process of V. natans accelerated the consumption of dissolved oxygen, leading to increase in the populations of methanogen (153.3 % increase of mcrA genes) and subsequently elevating CH4 emission fluxes (23.7 %) under high nutrient concentrations. Conversely, V. natans increased the available organic carbon under low nutrient conditions by radial oxygen loss, further increasing CH4 emission fluxes (94.7 %). Quantitative genetic and modeling analyses revealed that plant restoration processes drive ecological niche differentiation of methanogenic and methane oxidation microorganisms, affecting methane release fluxes within the restored area. The speciation process of V. natans is incapable of simultaneously meeting improved water purification and reduced methane emissions goals.