Patrick W. Sweeney

Macroecological research aims to understand factors influencing species composition and diversity. Understanding the distribution patterns of species is essential for prioritizing areas for conservation. This study investigates the alpha (α) and beta (β) diversity facets of Fagaceae across past (historical), present, and future timelines in Southwestern China. We used over 11,000 geographical observations to predict the spatial patterns of the α- and β-diversity of 120 species. We modeled the α-diversity via stacking prediction using an individual species distribution model at 50 km × 50 km grid cells. We used Sørensen dissimilarity to quantify total β-diversity and its components - turnover (β SIM) and nestedness (β NES). We integrated climate variables along with topographic and plant trait predictors to understand the species diversity. Finally, simultaneous autoregression (SAR) model was used to evaluate the effects of predictor variables on the α- and β-diversity patterns. Our results indicate a projected decline in α-diversity and an increase in β-diversity in the future. The findings underscore that the species β SIM is a driving factor of differing species composition during the past and present periods, while β NES will be a dominant factor in the future. Similarly, climatic and topographic factors significantly influenced the α-diversity and the β-diversity. In the future, climatic variables will play a significant role in determining the diversity patterns. By closely studying how various species respond and adapt to these changes, we can gain valuable insights into the dynamics of ecosystems and the potential threats to biodiversity.

Valeriana jatamansi Jones, a potential ethno-medicinal herb of global importance faced an unprecedented threat of its habitat loss due to burgeoning global demand. Genome-wide microsatellites or simple sequence repeats (SSRs) marker resources are advantageous, unfortunately, such larger resources have not been explored for genetic improvement in V. jatamansi. In the present study, transcriptome-derived functionally relevant microsatellite marker resources comprising 7957 SSR markers with significant homology (66.3 %) with public functional databases were created. Interestingly, 103 putative functional SSR markers derived from unigenes exhibited substantial annotations with secondary metabolite biosynthesis, transcription factors, and transporters were synthesized and experimentally validated in diverse genotypes. SSR loci with good marker attributes (average alleles/ locus: 7.5; PIC: 0.44; resolving power: 5.25) were successfully utilized for genetic population structure analysis of 525 genotypes representing 29 geographically diverse populations. Despite representing three genetic populations, north-western Indian Himalayan regions (wIHR) exhibited with low genetic diversity (h: 0.22) with moderate gene flow (Nm: 0.97) and high molecular variance (71 %) within population. Moreover, the predicted core of 53 genotypes representing 21 diverse populations was validated successfully using NJ clustering and regression correlation (R 2 > 0.85). Additionally, future habitat suitability is predicted to decline in at least 49.89 % habitat area of V. jatamansi. Hence, climatic zones with improved suitability can be potential geographical areas for its conservation and sustainable cultivation. The current findings including huge molecular markers resources, diversity inferences, and identification of core collections will facilitate gene bank management, selection of potential parental groups/ cultivars for implementation of molecular breeding strategies, genetic improvement, and sustainable cultivations of V. jatamansi for industrial utilization.

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.

Biological invasions pose a global challenge, affecting ecosystems worldwide and human societies. Knowledge of the evolutionary history of invasive species is critical to understanding their current invasion success and projecting their future spread. However, to date, few studies have addressed the evolutionary history and potential future spread of invaders simultaneously. In this study, we explored both evolutionary history and spatiotemporal dynamic patterns of the distribution of Reynoutria japonica, known as one of the world's worst plant invaders. We analysed 265 R. japonica samples from its current geographical ranges across three continents, using seven chloroplast DNA (cpDNA) markers to establish the phylogenetic relationships among extant populations. We combined these with ecological niche modelling to infer historical and more recent migration patterns and predict potential future distribution changes under climate change. Our results indicate that climate fluctuations and sea level changes likely facilitated the expansion of R. japonica from southern Japan to continental East Asia in the Pliocene, followed by a contraction in East Asian populations. In the recent Holocene, human activities have then enabled a linage of this species to spread from Japan to Europe and North America, resulting in three major global clades. Future climate scenarios suggest a northward expansion of R. japonica in Europe and North America, but shrinking habitat in China. Our study, thus, demonstrates the complex influences of historical climate‐driven migrations, human activities and future climate changes on the global distribution of an invasive species.

根据最新分类系统更新中国葡萄科(Vitaceae)特有种名录,整合点分布数据和县级面分布数据,绘制葡萄科特有种、广布特有种和狭域特有种的分布中心,利用MaxEnt模型模拟未来气候变化下部分中国葡萄科特有种的适生区,识别出值得重点关注的未来分布范围缩小的物种.结果显示:中国葡萄科特有种丰富,共有12属94种,热点地区主要集中在华中、东南及西南地区.中国葡萄科狭域特有种热点地区主要集中在西南边境和东南沿海地区,而广布特有种的分布格局与所有特有种的基本一致.MaxEnt模型模拟结果显示:在未来气候条件下,中国葡萄科42种特有种中有33种未来的总适生区和高适生区均呈现明显扩大趋势,9种未来的总适生区或高适生区呈现明显缩小趋势;中国葡萄科42种特有种中有37种的未来总适生区呈现向北部高纬度地区或西部高海拔地区迁移的趋势.综上所述,中国葡萄科特有种热点地区均位于中国生物多样性极其丰富的区域,但部分热点地区附近的保护地面积小且分布零散,保护效力偏低.建议就近整合零散的保护地,建立面积更大、连通性更高的国家公园或自然保护区.

Abstract After many decades of effective control of stem rust caused by the Puccinia graminis f.sp. tritici, (hereafter Pgt) the reported emergence of race TTKSK/Ug99 of Pgt in Uganda reignited concerns about epidemics worldwide because ∼90% of world wheat cultivars had no resistance to the new race. Since it was initially detected in Uganda in 1998, Ug99 variants have now been identified in thirteen countries in Africa and the Middle East. Stem rust has been a major problem in the past, and concern is increasing about the risk of return to Central and East Asia. Whilst control programs in North America and Europe relied on the use of resistant cultivars in combination with eradication of barberry (Berberis spp.), the alternate host required for the stem rust pathogen to complete its full lifecycle, the focus in East Asia was principally on the use of resistant wheat cultivars. Here, we investigate potential airborne transmission pathways for stem rust outbreaks in the Middle East to reach East Asia using an integrated modelling framework combining estimates of fungal spore deposition from an atmospheric dispersion model, environmental suitability for spore germination, and crop calendar information. We consider the role of mountain ranges in restricting transmission pathways, and we incorporate a representation of a generic barberry species into the lifecycle. We find viable transmission pathways to East Asia from the Middle East to the north via Central Asia and to the south via South Asia and that an initial infection in the Middle East could persist in East Asia for up to three years due to the presence of the alternate host. Our results indicate the need for further assessment of barberry species distributions in East Asia and appropriate methods for targeted surveillance and mitigation strategies should stem rust incidence increase in the Middle East region.

Saussurea is one of the largest and most rapidly evolving genera within the Asteraceae, comprising approximately 520 species from the Northern Hemisphere. A comprehensive infrageneric classification, supported by robust phylogenetic trees and corroborated by morphological and other data, has not yet been published. For the first time, we recovered a well-resolved nuclear phylogeny of Saussurea consisting of four main clades, which was also supported by morphological data. Our analyses show that ancient hybridization is the most likely source of deep cytoplasmic-nuclear conflict in Saussurea, and a phylogeny based on nuclear data is more suitable than one based on chloroplast data for exploring the infrageneric classification of Saussurea. Based on the nuclear phylogeny obtained and morphological characters, we proposed a revised infrageneric taxonomy of Saussurea, which includes four subgenera and 13 sections. Specifically, 1) S. sect. Cincta, S. sect. Gymnocline, S. sect. Lagurostemon, and S. sect. Strictae were moved from S. subg. Saussurea to S. subg. Amphilaena, 2) S. sect. Pseudoeriocoryne was moved from S. subg. Eriocoryne to S. subg. Amphilaena, and 3) S. sect. Laguranthera was moved from S. subg. Saussurea to S. subg. Theodorea.

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.

Non‐native annual grasses can dramatically alter fire frequency and reduce forage quality and biodiversity in the ecosystems they invade. Effective management techniques are needed to reduce these undesirable invasive species and maintain ecosystem services. Well‐timed management strategies, such as grazing, that are applied when invasive grasses are active prior to native plants can control invasive species spread and reduce their impact; however, anticipating the timing of key phenological stages that are susceptible to management over vast landscapes is difficult, as the phenology of these species can vary greatly over time and space. To address this challenge, we created range‐wide phenology forecasts for two problematic invasive annual grasses: cheatgrass (Bromus tectorum), and red brome (Bromus rubens). We tested a suite of 18 mechanistic phenology models using observations from monitoring experiments, volunteer science, herbarium records, timelapse camera imagery, and downscaled gridded climate data to identify the models that best predicted the dates of flowering and senescence of the two invasive grass species. We found that the timing of flowering and senescence of cheatgrass and red brome were best predicted by photothermal time models that had been adjusted for topography using gridded continuous heat‐insolation load index values. Phenology forecasts based on these models can help managers make decisions about when to schedule management actions such as grazing to reduce undesirable invasive grasses and promote forage production, quality, and biodiversity in grasslands; to predict the timing of greatest fire risk after annual grasses dry out; and to select remote sensing imagery to accurately map invasive grasses across topographic and latitudinal gradients. These phenology models also have the potential to be operationalized for within‐season or within‐year decision support.

The first record of Xenoglossa (Cemolobus) ipomoeae (Robertson, 1891) (Apidae: Eucerini) for the state of Mississippi, USA is reported. This species is a rarely encountered specialist bee that is known to forage on Ipomoea pandurata (L.) G.F.W. Mey (Convolvulaceae), potentially along with other closely related plants in the genus Ipomoea. A single female was collected in Bolivar County during 2017 that a represents a significant southwestern range expansion for this bee species.