Peter Derek Sell

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.

Rubus (Rosaceae), one of the most complicated angiosperm genera, contains about 863 species, and is notorious for its taxonomic difficulty. The most recent (1910–1914) global taxonomic treatment of the genus was conducted by Focke, who defined 12 subgenera. Phylogenetic results over the past 25 years suggest that Focke's subdivisions of Rubus are not monophyletic, and large‐scale taxonomic revisions are necessary. Our objective was to provide a comprehensive phylogenetic analysis of the genus based on an integrative evidence approach. Morphological characters, obtained from our own investigation of living plants and examination of herbarium specimens are combined with chloroplast genomic data. Our dataset comprised 196 accessions representing 145 Rubus species (including cultivars and hybrids) and all of Focke's subgenera, including 60 endemic Chinese species. Maximum likelihood analyses inferred phylogenetic relationships. Our analyses concur with previous molecular studies, but with modifications. Our data strongly support the reclassification of several subgenera within Rubus. Our molecular analyses agree with others that only R. subg. Anoplobatus forms a monophyletic group. Other subgenera are para‐ or polyphyletic. We suggest a revised subgeneric framework to accommodate monophyletic groups. Character evolution is reconstructed, and diagnostic morphological characters for different clades are identified and discussed. Based on morphological and molecular evidence, we propose a new classification system with 10 subgenera: R. subg. Anoplobatus, R. subg. Batothamnus, R. subg. Chamaerubus, R. subg. Cylactis, R. subg. Dalibarda, R. subg. Idaeobatus, R. subg. Lineati, R. subg. Malachobatus, R. subg. Melanobatus, and R. subg. Rubus. The revised infrageneric nomenclature inferred from our analyses is provided along with synonymy and type citations. Our new taxonomic backbone is the first systematic and complete global revision of Rubus since Focke's treatment. It offers new insights into deep phylogenetic relationships of Rubus and has important theoretical and practical significance for the development and utilization of these important agronomic crops.

The strength of interactions between plants and river processes is mediated by plant traits and fluvial conditions, including above‐ground biomass, stem density and flexibility, channel and bed material properties, and flow and sediment regimes. In many rivers, concurrent changes in 1) the composition of riparian vegetation communities as a result of exotic species invasion and 2) shifts in hydrology have altered physical and ecological conditions in a manner that has been mediated by feedbacks between vegetation and morphodynamic processes. We review how Tamarix, which has invaded many U.S. Southwest waterways, and Populus species, woody pioneer trees that are native to the region, differentially affect hydraulics, sediment transport, and river morphology. We draw on flume, field, and modeling approaches spanning the individual seedling to river‐corridor scales. In a flume study, we found differences in the crown morphology, stem density, and flexibility of Tamarix compared to Populus influenced near‐bed flow velocities in a manner that favored aggradation associated with Tamarix. Similarly, at the patch and corridor scales, observations confirmed increased aggradation with increased vegetation density. Furthermore, long‐term channel adjustments were different for Tamarix‐ versus Populus‐dominated reaches, with faster and greater geomorphic adjustments for Tamarix. Collectively, our studies show how plant‐trait differences between Tamarix and Populus, from individual seedlings to larger spatial and temporal scales, influence the co‐adjustment of rivers and riparian plant communities. These findings provide a basis for predicting changes in alluvial riverine systems which we conceptualize as a Green New Balance model that considers how channels may adjust to changes in plant traits and community structure in additional to alterations in flow and sediment supply. We offer suggestions regarding how the Green New Balance can be used in management and invasive species management.

In this study, we analyzed the distribution and the spatial pattern of species diversity of vascular plants in Nepal. The aim was to identify and evaluate the occurrence and status of species‐rich areas in Nepal using ecological and environmental drivers. We used 52,973 georeferenced herbarium specimen records, representing 2650 species collected from Nepal. Altogether, 41 environmental variables were used for model development and validation. We used MaxEnt to predict the distribution pattern. All the significant species distribution predictions were then used to develop a species richness and endemism pattern in Nepal. The High Mountain and Himalaya, particularly east and central Nepal, were found to be species diverse and endemically rich areas, whereas western Nepal had lower species richness. We observed that isothermality, slope, rugosity, potential evapotranspiration, precipitation of humid months, temperature annual range, mean diurnal range, and normalized difference in vegetation index of humid months were the most influential environmental and climatic variables. We observed that about 60% of the areas, which had highest richness and endemism values, are still not included in protected areas in Nepal. We quantitatively analyzed the species richness and endemicity patterns of Nepal and were able to identify 19 areas of high species diversity and endemicity, six of which are newly identified.

Morphometry and diagnosis of Rhinomias forticornis (Boheman, 1842) are given. Distribution of Rhinomias forticornis is analyzed using known occurrences, original ecological data, correlative species distribution modeling with aspect on Last Glacial Maximum environment are given. To achieve a more re…

In the 21st century, stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is still the most devastating disease of wheat globally. Despite the critical roles of the alternate host plants, the Berberis species, in the sexual reproduction and spread of Pst, the climate change impacts on t…

Aim: Due to the sessile nature of flowering plants, movements to new geographical areas occur mainly during seed dispersal. Frugivores tend to be efficient dispersers because animals move within the boundaries of their preferable niches, so seeds are more likely to be transported to environments tha…

The Qinghai-Tibetan Plateau (QTP) harbors abundant and diverse plant life owing to its high habitat heterogeneity. However, the distribution pattern of biodiversity hotspots and their conservation status remain unclear. Based on 148,283 high-resolution occurrence coordinates of 13,450 seed plants, w…

Question: Do invasions by invasive plant species with contrasting trait profiles (Arctotheca calendula, Carpobrotus spp., Conyza bonariensis, and Opuntia dillenii) change the climatic niche of coastal plant communities? Location: Atlantic coastal habitats in Huelva (Spain). Methods: We identifi…

Aim: When alien species are introduced to new ranges, climate or trait mismatches may initially constrain their population growth. However, inter‐ and intraspecific selection in the new environment should cause population growth rates to increase with residence time. Using a species‐for‐time approac…