Widespread homogenization of plant communities in the Anthropocene

The global human impact on biodiversity

Human activities drive a wide range of environmental pressures, including habitat change, pollution and climate change, resulting in unprecedented effects on biodiversity1,2. However, despite decades of research, generalizations on the dimensions and extent of human impacts on biodiversity remain ambiguous. Mixed views persist on the trajectory of biodiversity at the local scale3 and even more so on the biotic homogenization of biodiversity across space4,5. We compiled 2,133 publications covering 97,783 impacted and reference sites, creating an unparallelled dataset of 3,667 independent comparisons of biodiversity impacts across all main organismal groups, habitats and the five most predominant human pressures1,6. For all comparisons, we quantified three key measures of biodiversity to assess how these human pressures drive homogenization and shifts in composition of biological communities across space and changes in local diversity, respectively. We show that human pressures distinctly shift community composition and decrease local diversity across terrestrial, freshwater and marine ecosystems. Yet, contrary to long-standing expectations, there is no clear general homogenization of communities. Critically, the direction and magnitude of biodiversity changes vary across pressures, organisms and scales at which they are studied. Our exhaustive global analysis reveals the general impact and key mediating factors of human pressures on biodiversity and can benchmark conservation strategies.

Divergent alpha and beta diversity trends of soil nematode fauna along gradients of environmental change in the Carpathian Ecoregion

There is a significant lack of research on how climate change influences long-term temporal trends in the biodiversity of soil organisms. Nematodes may be specifically adequate to test soil biodiversity changes, because they account for ~80% of all Metazoans and play key roles in the functioning of terrestrial ecosystems. Here, we report on the first synthesis study focused on temporal trends of nematode fauna over a period of 14 years (1986-1999) across the Carpathian Ecoregion. We provide new evidence that wetter conditions associated to global change contributes to driving nematode diversity at genus/family level. We observed opposite trends in soil nematode alpha diversity (increase) and beta diversity (decrease) consistent across ecosystem types and soil horizons, providing strong evidence for the influence of climate change on soil biodiversity at large spatial scales. An increase in the community functional uniformity along with a decline in beta diversity indicated more homogenous soil conditions over time. The Soil Stability Index (metric devised to assess soil homeostasis based on the functional composition of nematode communities) increased over time, indicating a decline of soil disturbances and more complex soil food webs. Our results highlight the importance of nematodes as powerful indicators of soil biodiversity trends affected by multiple facets of environmental change in long-term soil monitoring.

The global land-water-climate nexus of drought-tolerant succulent plants for bioenergy in abandoned croplands and arid marginal lands

Bioenergy is considered among the main mitigation strategies to meet a green-growth development paradigm of 1.5 °C. However, climate change has been dramatically restructuring agriculture and damaging crops, threatening the achievement of global food security and bioenergy goals. Studies have shown that succulent plants through their water efficient and highly temperature-drought-tolerant Crassulacean Acid Metabolism (CAM) pathway, could be a key opportunity to meet future energy demands under global change scenarios. However, specific bioenergy potentials under alternative management conditions, irrigation, and land availability that minimize resource conflicts with food production, biodiversity transgressions, or water withdrawals in water scarce regions, remain unclear. Here, we estimate under a bottom-up approach the global bioenergy potentials of four relevant CAM species on recently abandoned croplands and arid marginal lands, unravelling the interdependencies between land availability, water requirements and climatic conditions at the global scale. We identify a potential of 16-36 Ej yr-1 (27-62% of current bioenergy demand) in abandoned croplands depending on local and management factors. Rainfed CAM potentials (16 Ej yr-1) are comparable with the potentials of bioenergy crops such as miscanthus (19 Ej yr-1) under similar environmental conditions. However, the water requirement of CAM species to reach this potential is 24-30% of what is expected for C3 and C4 bioenergy crops. Additionally, we identify a carbon sequestration potential via plant growth of -3.09 Pg C yr-1 between 1960 and 2020, which reveals an underestimated opportunity in arid marginal lands. We highlight the remarkable contribution of the CAM pathway as a nature-based solution under global change scenarios.

Unifying spatial scaling laws of biodiversity and ecosystem stability

While both species richness and ecosystem stability increase with area, how these scaling patterns are linked remains unclear. Our theoretical and empirical analyses of plant and fish communities show that the spatial scaling of ecosystem stability is determined primarily by the scaling of species asynchrony, which is in turn driven by the scaling of species richness. In wetter regions, plant species richness and ecosystem stability both exhibit faster accumulation with area, implying potentially greater declines in biodiversity and stability following habitat loss. The decline in ecosystem stability after habitat loss can be delayed, creating a stability debt mirroring the extinction debt of species. By unifying two foundational scaling laws in ecology, our work underscores that ongoing biodiversity loss may destabilize ecosystems across spatial scales.

Urbanization drives biotic homogenization of the avian community in China

Urbanization-driven biotic homogenization has been recorded in various ecosystems on local and global scales; however, it is largely unexplored in developing countries. Empirical studies on different taxa and bioregions show conflicting results (i.e. biotic homogenization vs. biotic differentiation); the extent to which the community composition changes in response to anthropogenic disturbances and the factors governing this process, therefore, require elucidation. Here, we used a compiled database of 760 bird species in China to quantify the multiple-site β-diversity and fitted distance decay in pairwise β-diversities between natural and urban assemblages to assess whether urbanization had driven biotic homogenization. We used generalized dissimilarity models (GDM) to elucidate the roles of spatial and environmental factors in avian community dissimilarities before and after urbanization. The multiple-site β-diversities among urban assemblages were markedly lower than those among natural assemblages, and the distance decays in pairwise similarities in natural assemblages were more rapid. These results were consistent among taxonomic, phylogenetic, and functional aspects, supporting a general biotic homogenization driven by urbanization. The GDM results indicated that geographical distance and temperature were the dominant predictors of avian community dissimilarity. However, the contribution of geographical distance and climatic factors decreased in explaining compositional dissimilarities in urban assemblages. Geographical and environmental distances accounted for much lower variations in compositional dissimilarities in urban than in natural assemblages, implying a potential risk of uncertainty in model predictions under further climate change and anthropogenic disturbances. Our study concludes that taxonomic, phylogenetic, and functional dimensions elucidate urbanization-driven biotic homogenization in China.

Plant Translocations in France: Identifying Gaps between Knowledge, Practice and Perception by Conservation Actors

In the current context of global changes, threatened flora is declining and homogenising at the expense of rare and protected species. Among conservation biology and ecological restoration techniques, plant translocation is one of the recommendations increasingly used. However, translocation remains risky and is recommended as a last resort to conserve protected flora in land use planning. Furthermore, it raises ethical questions partly linked to genetic processes. In this context, we studied how plant translocations are perceived by conservation actors in France, including their genetic aspects. The analysis of translocation perception complements that of feedback on concrete translocation operations and allows us to provide a qualitative assessment of current practices. We have adopted an interdisciplinary approach to survey different types of actors in nature conservation, involved or not in at least one stage of translocation operations (preparation, implementation and monitoring). Three main types of translocation perception divide our sample quite strongly (50% favourable/ 45% unfavourable/ 5% undecided). Surprisingly, their professional activity or the level of involvement in such an operation have no influence on their opinion on translocation, nor on the proposals of alternative measures. Only 15% of the actors involved in translocations used genetic data at least once. To conclude, it would be necessary to promote the sharing of feedback from past experiences. This would allow an up-to-date list of species unacceptable for translocation. Comparing the results of different protocols and implementation conditions for the same species or group should improve overall translocation success rates.

Widespread homogenization in vegetation activities along the elevational gradients across the Himalaya over the past 40 years

Mountainous regions are vital biodiversity hotspots with high heterogeneity, providing essential refugia for vegetation. However, climate change threatens this diversity with the potential homogenization of the distinct environmental conditions at different elevations. Here, we used a time-series (1985-2023) of Normalized Difference Vegetation Index (NDVI) from Landsat archives (30 m) to quantify vegetation changes across an elevation gradient on Himalaya Mountain. Our analysis revealed that over the past 40 years, the Himalayas have experienced widespread greening, accompanied by homogenization of vegetation across elevations. This homogenization, characterized by a reduction in the differences between high and low elevations, can be attributed to two main factors: (1) increased warming and a higher snowmelt rate at high elevations, facilitating rapid changes in high-elevation vegetation activities; and (2) higher anthropogenic disturbance at low and mid elevations, thus inhibiting low-elevation vegetation. These factors have resulted in a reduction of habitat differentiation along the mountain slopes, homogenizing vegetation and potentially threatening the unique biodiversity adapted to specific elevational zones. Our findings emphasize the urgent need for conservation strategies that prioritize the protection of heterogeneous mountain habitats to preserve their rich biodiversity in the face of climate change.

Climate change alters the future of natural floristic regions of deep evolutionary origins

Biogeographic regions reflect the organization of biotas over long evolutionary timescales but face alterations from recent anthropogenic climate change. Here, we model species distributions for 189,269 vascular plant species of the world under present and future climates and use this data to generate biogeographic regions based on phylogenetic dissimilarity. Our analysis reveals declines in phylogenetic beta diversity for years 2040 to 2100, leading to a future homogenization of biogeographic regions. While some biogeographic boundaries will persist, climate change will alter boundaries separating biogeographic realms. Such boundary alterations will be determined by altitude variation, heterogeneity of temperature seasonality, and past climate velocity. Our findings suggest that human activities may now surpass the geological forces that shaped floristic regions over millions of years, calling for the mitigation of climate impacts to meet international biodiversity targets.

Predicting undetected native vascular plant diversity at a global scale

Vascular plants are diverse and a major component of terrestrial ecosystems, yet their geographic distributions remain incomplete. Here, I present a global database of vascular plant distributions by integrating species distribution models calibrated to species' dispersal ability and natural habitats to predict native range maps for 201,681 vascular plant species into unsurveyed areas. Using these maps, I uncover unique patterns of native vascular plant diversity, endemism, and phylogenetic diversity revealing hotspots in underdocumented biodiversity-rich regions. These hotspots, based on detailed species-level maps, show a pronounced latitudinal gradient, strongly supporting the theory of increasing diversity toward the equator. I trained random forest models to extrapolate diversity patterns under unbiased global sampling and identify overlaps with modeled estimations but unveiled cryptic hotspots that were not captured by modeled estimations. Only 29% to 36% of extrapolated plant hotspots are inside protected areas, leaving more than 60% outside and vulnerable. However, the unprotected hotspots harbor species with unique attributes that make them good candidates for conservation prioritization.

Floristic diversity and its relationships with human land use varied regionally during the Holocene

Humans have caused growing levels of ecosystem and diversity changes at a global scale in recent centuries but longer-term diversity trends and how they are affected by human impacts are less well understood. Analysing data from 64,305 pollen samples from 1,763 pollen records revealed substantial community changes (turnover) and reductions in diversity (richness and evenness) in the first ~1,500 to ~4,000 years of the Holocene epoch (starting 11,700 years ago). Turnover and diversity generally increased thereafter, starting ~6,000 to ~1,000 years ago, although the timings, magnitudes and even directions of these changes varied among continents, biomes and sites. Here, modelling these diversity changes, we find that most metrics of biodiversity change are associated with human impacts (anthropogenic land-cover change estimates for the last 8,000 years), often positively but the magnitudes, timings and sometimes directions of associations differed among continents and biomes and sites also varied. Once-forested parts of the world tended to exhibit biodiversity increases while open areas tended to decline. These regionally specific relationships between humans and floristic diversity highlight that human-biodiversity relationships have generated positive diversity responses in some locations and negative responses in others, for over 8,000 years.

Environmental determinants of phylogenetic diversity in vernal pool habitats

Phylogenetic diversity offers critical insights into the ecological dynamics shaping species composition and ecosystem function, thereby informing conservation strategies. Despite its recognized importance in ecosystem management, the assessment of phylogenetic diversity in endangered habitats, such as vernal pools, remains limited. Vernal pools, characterized by cyclical inundation and unique plant communities, present an ideal system for investigating the interplay between ecological factors and phylogenetic structure. This study aims to characterize the phylogenetic patterns of vernal pools and their associated vegetation zones, addressing questions about taxonomic and phylogenetic community discreteness, the role of flooding as a habitat filter, the influence of invasive species on phylogenetic structure, and the impact of seasonal variation on phylogenetic diversity. I find that zones-of-vegetation exhibit high between zone taxonomic and phylogenetic beta diversity whereas each zone forms a unique cluster, suggesting that zones are taxonomically and phylogenetically discrete units. Regions of high-inundation pressure exhibit phylogenetic clustering, indicating that flooding is a habitat filter in vernal pool habitats. Competition between native species conform to the 'competitive relatedness hypothesis' and, conversely, communities dominated by invasive Eurasian grass species are phylogenetically clustered. In addition, I find that phylogenetic diversity within zones fluctuates across the spring season in response to changing water levels, precipitation, and temperature. By analyzing three pools within the Merced Vernal Pool and Grassland Reserve, this research elucidates the phylogenetic dynamics of vernal pools. The findings underscore the need for tailored conservation strategies that account for the unique ecological characteristics of each vegetation zone within vernal pool habitats.

The human side of biodiversity: coevolution of the human niche, palaeo-synanthropy and ecosystem complexity in the deep human past

Today's biodiversity crisis fundamentally threatens the habitability of the planet, thus ranking among the primary human challenges of our time. Much emphasis is currently placed on the loss of biodiversity in the Anthropocene, yet these debates often portray biodiversity as a purely natural phenomenon without much consideration of its human dimensions and frequently lack long-term vistas. This paper offers a deep-time perspective on the key role of the evolving human niche in ecosystem functioning and biodiversity dynamics. We summarize research on past hunter-gatherer ecosystem contributions and argue that human-environment feedback systems with important biodiversity consequences are probably a recurrent feature of the Late Pleistocene, perhaps with even deeper roots. We update current understandings of the human niche in this light and suggest that the formation of palaeo-synanthropic niches in other animals proffers a powerful model system to investigate recursive interactions of foragers and ecosystems. Archaeology holds important knowledge here and shows that ecosystem contributions vary greatly in relation to different human lifeways, some of which are lost today. We therefore recommend paying more attention to the intricate relationship between biodiversity and cultural diversity, contending that promotion of the former depends on fostering the latter. This article is part of the theme issue 'Ecological novelty and planetary stewardship: biodiversity dynamics in a transforming biosphere'.

Land conversion to agriculture induces taxonomic homogenization of soil microbial communities globally

Agriculture contributes to a decline in local species diversity and to above- and below-ground biotic homogenization. Here, we conduct a continental survey using 1185 soil samples and compare microbial communities from natural ecosystems (forest, grassland, and wetland) with converted agricultural land. We combine our continental survey results with a global meta-analysis of available sequencing data that cover more than 2400 samples across six continents. Our combined results demonstrate that land conversion to agricultural land results in taxonomic and functional homogenization of soil bacteria, mainly driven by the increase in the geographic ranges of taxa in croplands. We find that 20% of phylotypes are decreased and 23% are increased by land conversion, with croplands enriched in Chloroflexi, Gemmatimonadota, Planctomycetota, Myxcoccota and Latescibacterota. Although there is no significant difference in functional composition between natural ecosystems and agricultural land, functional genes involved in nitrogen fixation, phosphorus mineralization and transportation are depleted in cropland. Our results provide a global insight into the consequences of land-use change on soil microbial taxonomic and functional diversity.

AI-based discovery of habitats from museum collections

Museum collection records are a source of historic data for species occurrence, but little attention is paid to the associated descriptions of habitat at the sample locations. We propose that artificial intelligence methods have potential to use these descriptions for reconstructing past habitat, to address ecological and evolutionary questions.

Achieving the impossible: prevention and eradication of invasive plants in Mediterranean-type ecosystems

An in-depth analysis of the mechanistic processes underlying the evolution and ecophysiology of typical invasive plants such as Carpobrotus spp., Acacia spp., Agave spp., and Opuntia spp. in Mediterranean-type ecosystems shows very sophisticated, complex, and efficient strategies for invasion success, particularly in fragmented habitats. Propagule pressure at both geographical and temporal scales and the establishment of long-term seed banks are determinant for invasion success. A two-sword strategy based on long-term prevention and eradication is proposed for the management of Mediterranean-type ecosystems. Eradication of invasive plants in Mediterranean-type ecosystems appears to be extremely difficult nowadays and, at least for some invaders like Carpobrotus spp., long-term approaches that ultimately culminate in the elimination of seed banks is the only path for success.

The invasive legume Lupinus polyphyllus has minor site-specific impacts on the composition of soil bacterial communities

Plant invasions can have major impacts on ecosystems, both above- and belowground. In particular, invasions by legumes, which often host nitrogen-fixing symbionts (rhizobia), are known to modify soil bacterial communities. Here, we examined the effect of the invasive herbaceous legume Lupinus polyphyllus on the alpha diversity and community composition of soil bacteria. We also explored the relationships between these bacterial communities and vegetation cover, the cover of other (non-invasive) legumes, or the number of vascular plants present. For this, we sampled rhizosphere soil and surveyed vegetation from ten paired sites (uninvaded versus invaded more than 10 years ago) in southwestern Finland, and identified bacterial DNA using 16S rRNA gene amplicon sequencing. The presence of the plant invader and the three vegetation variables considered had no effect on the alpha diversity of soil bacteria in terms of bacterial richness or Shannon and Inverse Simpson diversity indices. However, the composition of soil bacterial communities differed between invaded and uninvaded soils at four out of the ten sites. Interestingly, the relative abundances of the top bacterial families in invaded and uninvaded soils were inconsistent across sites, including for legume-associated rhizobia in the family Bradyrhizobiaceae. Other factors-such as vegetation cover, legume cover (excluding L. polyphyllus), number of plant species-also explained a small proportion of the variation in bacterial community composition. Our findings indicate that L. polyphyllus has the potential to modify the composition of local soil bacterial community, at least in sites where it has been present for more than a decade.

Evolutionary history of host trees amplifies the dilution effect of biodiversity on forest pests

Biodiversity appears to strongly suppress pathogens and pests in many plant and animal systems. However, this "dilution effect" is not consistently detected, and when present can vary strikingly in magnitude. Here, we use forest inventory data from over 25,000 plots (>1.1 million sampled trees) to quantify the strength of the dilution effect on dozens of forest pests and clarify why some pests are particularly sensitive to biodiversity. Using Bayesian hierarchical models, we show that pest prevalence is frequently lower in highly diverse forests, but there is considerable variability in the magnitude of this dilution effect among pests. The strength of dilution was not closely associated with host specialization or pest nativity. Instead, pest prevalence was lower in forests where co-occurring tree species were more distantly related to a pest's preferred hosts. Our analyses indicate that host evolutionary history and forest composition are key to understanding how species diversity may dilute the impacts of tree pests, with important implications for predicting how future biodiversity change may affect the spread and distribution of damaging forest pests.

Contrasting impacts of non-native and threatened species on morphological, life history, and phylogenetic diversity in bird assemblages

Human activities have altered the species composition of assemblages through introductions and extinctions, but it remains unclear how those changes can affect the different facets of biodiversity. Here we assessed the impact of changes in species composition on taxonomic, functional, and phylogenetic diversity across 281 bird assemblages worldwide. To provide a more nuanced understanding of functional diversity, we distinguished morphological from life-history traits. We showed that shifts in species composition could trigger a global decline in avian biodiversity due to the high number of potential extinctions. Moreover, these extinctions were not random but unique in terms of function and phylogeny at the regional level. Our findings demonstrated that non-native species cannot compensate for these losses, as they are both morphologically and phylogenetically close to the native fauna. In the context of the ongoing biodiversity crisis, such alterations in the functional and phylogenetic structure of bird assemblages could heighten ecosystem vulnerability.

Future changes in key plant traits across Central Europe vary with biogeographical status, woodiness, and habitat type

Many plant traits covary with environmental gradients, reflecting shifts in adaptive strategies and thus informing about potential consequences of future environmental change for vegetation and ecosystem functioning. Yet, the evidence of trait-environment relationships (TERs) remains too heterogeneous for reliable predictions, partially due to insufficient consideration of trait syndromes specific to certain growth forms and habitats. Moreover, it is still unclear whether non-native and native plants' traits align similarly along environmental gradients, limiting our ability to assess the impacts of future plant invasions. Using a Bayesian multilevel modelling framework, we assess TERs for native and non-native woody and herbaceous plants across six broad habitat types in Central Europe at a resolution of c. 130 km2 and use them to project trait change under future environmental change scenarios until 2081-2100. We model TERs between three key plant traits (maximum height, Hmax; specific leaf area, SLA; seed mass, SM) and individual environmental factors (7 climate variables and % urban land cover) and estimate trait change summed across all environmental effects. We also quantify the change in the average trait difference between native and non-native plants. Our models depict multiple TERs, with important differences attributed to biogeographical status and woodiness within and across habitat types. The overall magnitude of trait change is projected to be greater for non-native than native taxa and to increase under more extreme scenarios. Native woody plant assemblages may generally experience a future increase across all three traits, whereas woody non-natives may decline in Hmax and increase in SLA and SM. Herbaceous Hmax is estimated to increase and SLA to decrease in most habitats. The obtained trait projections highlight conditions of competitive advantage of non-native plants over natives and vice versa and can serve as starting points for projecting future changes in ecosystem functions and services.

Systematic loss in biotic heterogeneity but not biodiversity across multiple trophic levels in Erhai lake, China

Anthropogenic disturbances and climate change have significantly altered the biotic composition across many ecosystems, leading to changes in biodiversity and even ecological collapse. An ecosystem comprises multiple trophic levels, and the issue how these disturbances affect their assembly processes remains unclear. Ecological stability of assemblages was maintained by their structure, and thus, revealing structure changes across trophic levels could improve our understanding of how ecosystems response to disturbances as a whole. In this study, we combined methods from palaeolimnology, ecology and network analysis, and observed the changes of biodiversity and network structure of two trophic levels (algae - diatoms and zoobenthos - chironomids) in Erhai lake, Southwest China over the last century. Results showed nutrient enrichment induced shifts in diatom and chironomid assemblages at ∼2001 CE, suggesting that the shift in Erhai lake may have occurred at multiple trophic levels. We found biodiversity exhibit different trends across trophic levels as it decreased in diatoms but increased in chironomids. However, network skewness declined in both trophic levels, indicating the common loss of biotic heterogeneity. The consistent decline of skewness among trophic levels long before the compositional shift is a potential parameter to warn of the shifts in lake ecosystems.

From Dormant Collections to Repositories for the Study of Habitat Changes: The Importance of Herbaria in Modern Life Sciences

In recent decades, the advent of new technologies for massive and automatized digitization, together with the availability of new methods for DNA sequencing, strongly increased the interest and relevance of herbarium collections for the study of plant biodiversity and evolution. These new approaches prompted new projects aimed at the creation of a large dataset of molecular and phenological data. This review discusses new challenges and opportunities for herbaria in the context of the numerous national projects that are currently ongoing, prompting the study of herbarium specimens for the understanding of biodiversity loss and habitat shifts as a consequence of climate changes and habitat destruction due to human activities. With regard to this, the National Biodiversity Future Center (active in Italy since 2022) started a large-scale digitization project of the Herbarium Centrale Italicum in Florence (Italy), which is the most important Italian botanical collection, consisting of more than 4 million samples at present.

Integrating biogeographic approach into classical biological control: Assessing the climate matching and ecological niche overlap of two natural enemies against common ragweed in China

Plant invasion is considered a high priority threat to biodiversity, ecosystems, the environment, and human health worldwide. Classical biological control (biocontrol) is a generally safer and more environmentally benign measure than chemical controls in managing invasive alien plants (IAPs). However, the impacts of climate change and the importance of climate matching in ensuring the efficiency of biocontrol candidates in controlling IAPs are likely to be underestimated. Here, based on the ensemble model and n-dimensional hypervolumes concepts, we estimated the overlapping areas between Ambrosia artemisiifolia and its two most effective natural enemies (Ophraella communa and Epiblema strenuana) under climate change in China. Moreover, we compared their ecological niches, further assessing the impact of climate change on the efficiency of two natural enemies in controlling A. artemisiifolia in China. We found that the potentially suitable areas of the two natural enemies and A. artemisiifolia were primarily influenced by temperature and human influence index variables. Under near-current climate, the overlapping area between O. communa and A. artemisiifolia was the largest, followed by E. strenuana and A. artemisiifolia, and both two natural enemies and A. artemisiifolia. The ecological niche between A. artemisiifolia and O. communa was most similar (0.64), followed by A. artemisiifolia and E. strenuana (0.55). The separate control (the niche separation areas of the two natural enemies against A. artemisiifolia) and joint-control (the niche overlap areas of the two natural enemies against A. artemisiifolia) efficiencies of the two natural enemies against A. artemisiifolia will both increase in future climates (the 2030s and 2050s) in northern and northeastern China. Our findings demonstrate a new approach to assess control efficiency and screen potential release areas of two natural enemies against A. artemisiifolia in China without the need for actual field release or experimentation. Moreover, our findings provide important clues for ensuring the classical biocontrol of IAPs worldwide.

Comparative genomics of widespread and narrow-range white-bellied rats in the Niviventer niviventer species complex sheds light on invasive rodent success

Widespread species that inhabit diverse environments possess large population sizes and exhibit a high capacity for environmental adaptation, thus enabling range expansion. In contrast, narrow-range species are confined to restricted geographical areas and are ecologically adapted to narrow environmental conditions, thus limiting their ability to expand into novel environments. However, the genomic mechanisms underlying the differentiation between closely related species with varying distribution ranges remain poorly understood. The Niviventer niviventer species complex (NNSC), consisting of highly abundant wild rats in Southeast Asia and China, offers an excellent opportunity to investigate these questions due to the presence of both widespread and narrow-range species that are phylogenetically closely related. In the present study, we combined ecological niche modeling with phylogenetic analysis, which suggested that sister species cannot be both widespread and dominant within the same geographical region. Moreover, by assessing heterozygosity, linkage disequilibrium decay, and Tajima's D analysis, we found that widespread species exhibited higher genetic diversity than narrow-range species. In addition, by exploring the "genomic islands of speciation", we identified 13 genes in highly divergent regions that were shared by the two widespread species, distinguishing them from their narrow-range counterparts. Functional annotation analysis indicated that these genes are involved in nervous system development and regulation. The adaptive evolution of these genes likely played an important role in the speciation of these widespread species.

Angiosperm phylogenetic diversity is lower in Africa than South America

Although originating from a common Gondwanan flora, the diversity and composition of the floras of Africa and South America have greatly diverged since continental breakup of Africa from South America now having much higher plant species richness. However, the phylogenetic diversity of the floras and what this tells us about their evolution remained unexplored. We show that for a given species richness and considering land surface area, topography, and present-day climate, angiosperm phylogenetic diversity in South America is higher than in Africa. This relationship holds regardless of whether all climatically matched areas or only matched areas in tropical climates are considered. Phylogenetic diversity is high relative to species richness in refugial areas in Africa and in northwestern South America, once the gateway for immigration from the north. While species richness is strongly influenced by massive plant radiations in South America, we detect a pervasive influence of historical processes on the phylogenetic diversity of both the South American and African floras.

Re-evaluating the importance of threatened species in maintaining global phytoregions

Anthropogenic introductions are known to be changing the structure of global phytogeographical regions (phytoregions), but previous studies have been limited by incomplete or biased data sets that are likely to underestimate the importance of threatened species. In this work, we analyse a comprehensive data set of all known species and their occurrences (at botanical country resolution) to quantify the impact of potential future extinction scenarios. We used Infomap, a network-based community detection algorithm, to generate phytoregional delineations for six species-distribution scenarios (native, introduced and extinctions of species that are either documented as threatened or likely to be threatened, as well as combinations thereof). We compared the numbers and sizes of phytoregions to characterise the amount and spatial distribution of changes in global phytoregions under each scenario. Extinctions of species that are predicted to be threatened had a greater homogenising effect on phytoregions than introductions, and there was some evidence that introductions may even mitigate the homogenisation caused by extinctions, though this interaction is complex. This research provides the first evidence that the loss of threatened species would have significant ramifications for global phytoregions and demonstrates the need to consider extinction processes in studies of anthropogenic effects on biodiversity patterns.

Why plant diversity and distribution matter

This article is the Editorial for the Special Collection ‘Global plant diversity and distribution’. See https://www.newphytologist.org/global-plant-diversity for more details.

North American pollen records provide evidence for macroscale ecological changes in the Anthropocene

Recent global changes associated with anthropogenic activities are impacting ecological systems globally, giving rise to the Anthropocene. Critical reorganization of biological communities and biodiversity loss are expected to accelerate as anthropogenic global change continues. Long-term records offer context for understanding baseline conditions and those trajectories that are beyond the range of normal fluctuation seen over recent millennia: Are we causing changes that are fundamentally different from changes in the past? Using a rich dataset of late Quaternary pollen records, stored in the open-access and community-curated Neotoma database, we analyzed changes in biodiversity and community composition since the end Pleistocene in North America. We measured taxonomic richness, short-term taxonomic loss and gain, first/last appearances (FAD/LAD), and abrupt community change. For all analyses, we incorporated age-model uncertainty and accounted for differences in sample size to generate conservative estimates. The most prominent signals of elevated vegetation change were seen during the Pleistocene-Holocene transition and since 200 calendar years before present (cal YBP). During the Pleistocene-Holocene transition, abrupt changes and FADs were elevated, and from 200 to -50 cal YBP, we found increases in short-term taxonomic loss, FADs, LADs, and abrupt changes. Taxonomic richness declined from ~13,000 cal YBP until about 6,000 cal YBP and then increased until the present, reaching levels seen during the end Pleistocene. Regionally, patterns were highly variable. These results show that recent changes associated with anthropogenic impacts are comparable to the landscape changes that took place as we moved from a glacial to interglacial world.

A latitudinal gradient in Darwin's naturalization conundrum at the global scale for flowering plants

Darwin's naturalization conundrum describes two seemingly contradictory hypotheses regarding whether alien species closely or distantly related to native species should be more likely to naturalize in regional floras. Both expectations have accumulated empirical support, and whether such apparent inconsistency can be reconciled at the global scale is unclear. Here, using 219,520 native and 9,531 naturalized alien plant species across 487 globally distributed regions, we found a latitudinal gradient in Darwin's naturalization conundrum. Naturalized alien plant species are more closely related to native species at higher latitudes than they are at lower latitudes, indicating a greater influence of preadaptation in harsher climates. Human landscape modification resulted in even steeper latitudinal clines by selecting aliens distantly related to natives in warmer and drier regions. Our results demonstrate that joint consideration of climatic and anthropogenic conditions is critical to reconciling Darwin's naturalization conundrum.

Vegetation-environment interactions: plant species distribution and community assembly in mixed coniferous forests of Northwestern Himalayas

One of the main goals of ecological studies is to disentangle the dynamics that underlie the spatiotemporal distribution of biodiversity and further functions of the ecosystem. However, due to many ecological and geopolitical reasons, many remote areas with high plant species diversity have not been assessed using newly based analytical approaches for vegetation characterization. Here, we classified and characterized different vegetation types (i.e., major plant communities) based on indicator species and on the influence of different environmental gradients in the Himalayan mixed coniferous forest, Pakistan. For that, we addressed the following questions: Does the vegetation composition of the Himalayan mixed coniferous forest correlate with climatic, topographic, geographic, and edaphic variables? Is it possible to identify plant communities through indicator species in relation to environmental gradients using multivariate approaches? Can this multivariate be helpful for conservation planning? During four consecutive years we assessed the vegetation composition and environmental variables (21 variables divided in geographic, climatic, topographic, and edaphic groups) of 156 50 m-trasects between an elevation of 2000-4000 m. Using newly based analytical approaches for community characterization, we found a total of 218 plant species clustered into four plant communities with the influence of environmental gradients. The highest index of similarity was recorded between Pinus-Cedrus-Viburnum (PCV) and Viburnum-Pinus-Abies (VPA) communities, and the highest index of dissimilarity was recorded between PCV and Abies-Juniperus-Picea (AJP) communities. Among these four communities, highest number of plant species (156 species) was recorded in PCV, maximum alpha diversity (H' = 3.68) was reported in VPA, highest Simpson index (0.961) and Pielou's evenness (0.862) were reported in VPA and AJP. The edaphic gradients (i.e., organic matter, phosphorous, pH and soil texture) and climatic factors (temperature, humidity) were the strongest environmental gradients that were responsible for structuring and hosting the diverse plant communities in mixed coniferous forest. Finally, the Himalayan mixed coniferous structure is more influenced by the spatial turnover beta-diversity process (βsim) than by the species loss (nestedness-resultant, βsne). Our analysis of the vegetation structure along the environmental gradient in the Himalayan mixed coniferous forest supported by sophisticated analytical approaches reveled indicator species groups, which are associated to specific microclimatic zones (i.e., vegetation communities). Within this focus, we side with the view that these results can support conservation planning and management for similar and different areas providing mitigating and preventive measures to reduce potential negative impacts, such as anthropic and climatic.

Zoonoses in a changing world

Animals are continuously exposed to pathogens but rarely get infected, because pathogens must overcome barriers to establish successful infections. Ongoing planetary changes affect factors relevant for such infections, such as pathogen pressure and pathogen exposure. The replacement of wildlife with domestic animals shrinks the original host reservoirs, whereas expanding agricultural frontiers lead to increased contact between natural and altered ecosystems, increasing pathogen exposure and reducing the area where the original hosts can live. Climate change alters species' distributions and phenology, pathogens included, resulting in exposure to pathogens that have colonized or recolonized new areas. Globalization leads to unwilling movement of and exposure to pathogens. Because people and domestic animals are overdominant planetwide, there is increased selective pressure for pathogens to infect them. Nature conservation measures can slow down but not fully prevent spillovers. Additional and enhanced surveillance methods in potential spillover hotspots should improve early detection and allow swifter responses to emerging outbreaks.

Disentangling spatiotemporal dynamics in metacommunities through a species-patch network approach

Colonization and extinction at local and regional scales, and gains and losses of patches are important processes in the spatiotemporal dynamics of metacommunities. However, analytical challenges remain in quantifying such spatiotemporal dynamics when species extinction-colonization and patch gain and loss processes act simultaneously. Recent advances in network analysis show great potential in disentangling the roles of colonization, extinction, and patch dynamics in metacommunities. Here, we developed a species-patch network approach to quantify metacommunity dynamics including (i) temporal changes in network structure, and (ii) temporal beta diversity of species-patch links and its components that reflect species extinction-colonization and patch gain and loss. Application of the methods to simulated datasets demonstrated that the approach was informative about metacommunity assembly processes. Based on three empirical datasets, our species-patch network approach provided additional information about metacommunity dynamics through distinguishing the effects of species colonization and extinction at different scales from patch gains and losses and how specific environmental factors related to species-patch network structure. In conclusion, our species-patch network framework provides effective methods for monitoring and revealing long-term metacommunity dynamics by quantifying gains and losses of both species and patches under local and global environmental change.

Neophytes may promote hybridization and adaptations to a changing planet

Human activities erode geographic barriers, facilitating hybridization among previously isolated taxa. However, limited empirical research exists on the consequences of introduced species (neophytes) for hybridization and subsequent evolutionary outcomes. To address this knowledge gap, we employed a macroecological approach. First, we examined the spatial and phylogenetic overlap between neophytes and hybrids by integrating the Plants of the World Online database with the Global Naturalized Alien Flora database. Second, leveraging the largest dated plant phylogeny available, we compared diversification rates between genera containing hybrids and neophytes versus those without. Third, focusing on the extensively studied hybrid flora of Britain, we studied the spatial distributions of hybrids in relation to neophyte and native parents, assessing potential adaptations to anthropogenic disturbances and impacts on native species. Overall, our findings highlight positive ties between contemporary biodiversity redistribution and hybridization. Spatially (across countries) and phylogenetically (across genera), neophyte incidence was positively associated with hybrid incidence. Genera comprising both hybrids and neophytes displayed significantly higher diversification rates. Neophyte hybrids primarily occupied areas with a higher human footprint, with limited evidence of hybrids threatening native species throughout their range in more natural habitats. These results challenge the notion that species naturalizations and hybridizations exclusively yield negative outcomes for biodiversity. While it is conceivable that anthropogenic hybridization may facilitate recombination of genetic variation and contribute to conserving genetic diversity in disturbed environments, further research is needed to fully understand these processes.

Looking back on biodiversity change: lessons for the road ahead

Estimating biodiversity change across the planet in the context of widespread human modification is a critical challenge. Here, we review how biodiversity has changed in recent decades across scales and taxonomic groups, focusing on four diversity metrics: species richness, temporal turnover, spatial beta-diversity and abundance. At local scales, change across all metrics includes many examples of both increases and declines and tends to be centred around zero, but with higher prevalence of declining trends in beta-diversity (increasing similarity in composition across space or biotic homogenization) and abundance. The exception to this pattern is temporal turnover, with changes in species composition through time observed in most local assemblages. Less is known about change at regional scales, although several studies suggest that increases in richness are more prevalent than declines. Change at the global scale is the hardest to estimate accurately, but most studies suggest extinction rates are probably outpacing speciation rates, although both are elevated. Recognizing this variability is essential to accurately portray how biodiversity change is unfolding, and highlights how much remains unknown about the magnitude and direction of multiple biodiversity metrics at different scales. Reducing these blind spots is essential to allow appropriate management actions to be deployed. This article is part of the theme issue 'Detecting and attributing the causes of biodiversity change: needs, gaps and solutions'.

Calling time on alien plantscapes

Both urban and rural environments around the globe have become dominated by alien plant species to the extent that plantscapes from one region or country have become difficult to distinguish from many others. This process of plant community homogenisation comes at a cost to cultural identity and undermines people's sense of place. Although invasive alien plant species have received considerable attention in recent decades, issues with non-invasive alien plant species have largely been ignored, and yet they contribute significantly to biotic homogeneity and impose an ever accumulating invasion debt: a debt that increases in proportion with their population sizes. By contrast, an abundance of native species in the places where people live is important for strengthening commitment to biodiversity conservation. Is there therefore sufficient evidence of harm from increasing numbers of non-invasive alien plants to justify local and central governments introducing measures to substantially reduce the proportion of non-invasive aliens in both urban and rural environments?

Reorganization of seagrass communities in a changing climate

Although climate change projections indicate significant threats to terrestrial biodiversity, the effects are much more profound and striking in the marine environment. Here we explore how different facets of locally distinctive α- and β-diversity (changes in spatial composition) of seagrasses will respond to future climate change scenarios across the globe and compare their coverage with the existing network of marine protected areas. By using species distribution modelling and a dated phylogeny, we predict widespread reductions in species' range sizes that will result in increases in seagrass weighted and phylogenetic endemism. These projected increases of endemism will result in divergent shifts in the spatial composition of β-diversity leading to differentiation in some areas and the homogenization of seagrass communities in other regions. Regardless of the climate scenario, the potential hotspots of these projected shifts in seagrass α- and β-diversity are predicted to occur outside the current network of marine protected areas, providing new priority areas for future conservation planning that incorporate seagrasses. Our findings report responses of species to future climate for a group that is currently under represented in climate change assessments yet crucial in maintaining marine food chains and providing habitat for a wide range of marine biodiversity.

Biological invasions: The secret domination of alien ants

Globalization has contributed to the spread of thousands of species, yet only a few harmful ones have attracted most attention. New evidence shows that introduced ants are a particularly important group of global invaders that can dominate native insect communities.

Radical shift in the genetic composition of New England chicory populations

Human activities have been altering the flora and fauna across the planet. Distributions and the diversity of species, and the phenotypes of individuals in those species are changing. New England with its rapidly changing human demographics is an ideal place to investigate these temporal changes in the habitat. The flora of New England consists of both native and nonnative species. Non-indigenous plant species have been introduced since the first Europeans arrived in North America in the 15th century. Cichorium intybus (chicory), native to Eurasia, was first recorded in North America in 1774. Subsequently, chicory spread and became naturalized throughout much of the continent.In this study, we used chloroplast DNA sequences and 12 microsatellite nuclear markers to assess the temporal genetic changes in New England populations of chicory. We analysed 84 herbarium specimens and 18 contemporary extant populations (228 individuals in total).Three chloroplast DNA haplotypes were detected and all were present in New England prior to 1890; however, Hap3 was rare prior to the 1950s. The nuclear DNA markers showed a major shift in the genetic diversity and composition, with all historical herbarium collections belonging to a single genetic cluster and 16 out of 18 contemporary chicory populations belonging to different genetic clusters. This change occurred regionally and also on a local scale with contemporary populations being very different from herbarium specimens collected previously in the corresponding localities. Synthesis. Our results indicate that the genetic diversity and structure of Cichorium intybus populations have changed substantially since the founding populations in New England. These changes may have contributed to the success of this nonnative species and helped to fuel its rapid expansion and adaptation to the changing landscapes in both New England and the rest of North America.

Understanding the taxonomic homogenization of road-influenced plant assemblages in the Qionglai mountain range: A functional and phylogenetic perspective

As an increasingly prevalent form of human activity, roads drive the taxonomic homogenization of mountain plant assemblages, threatening global biodiversity. However, little is known about how mountain roads impact functional and phylogenetic beta diversity and how these effects are related to taxonomic homogenization. To understand the mechanism of taxonomic homogenization triggered by mountain roads, we used species absence/presence data from 76 plots (2 m*50 m) and values for 12 traits measured on 978 species from the interior and roadside communities in the Qionglai mountain range, one of the temperate regions with the highest plant species richness in the world. We used a structural equation modeling approach (SEM) to consider several surrogates of road disturbance (changes in soil physicochemical properties and the presence or absence of roads) and the causal relationship between three facets of beta diversity (taxonomic beta diversity, TBD; functional beta diversity, FBD and phylogenetic beta diversity, PBD). The results suggest that TBD, FBD and PBD respond inconsistently to mountain roads, despite strong positive correlations between the three facets of plant beta diversity in the study area. Compared with the interior community, the βtotal.tax and βtotal.func of the roadside community decreased by 2.54% and 2.22%, respectively, which were related to the reduction of species and trait richness differences and replacements; however, we did not find the same results when assessing the changes in βtotal.phy, which represents tip-weighted PBD (twPBD). Furthermore, the largest effect of roads on beta diversity was reflected in basal-weighted PBD (bwPBD), which decreased by 9.97%, indicating that those species with fewer extant relatives and longer evolutionary histories are more sensitive to mountain roads. Therefore, it is necessary to take targeted protection measures for ancient species in roadside communities. In addition, we believe that it is still necessary to take measures to prevent the further dispersal of nonnative species, although the presence of non-native species in roadside plots has led to small changes in three facets of beta diversity. There were causal relationships between the three facets of beta diversity, but their intensity and sign different in the SEM of different components of beta diversity (i.e., richness difference and replacement). Our findings suggest that the homogenization of community species composition at the landscape scale arises by a combination of adaptive responses of the functional traits of organisms to environmental consistency (e.g., reduced the differences in soil variables) caused by roads and resorting or reassembly of community clades composition due to environmental filtering. These results contribute to our comprehensive understanding of the impact of mountain roads on plant diversity, which highlights the complex relationship between human pressure and biodiversity loss.

Historic samples reveal loss of wild genotype through domestic chicken introgression during the Anthropocene

Human activities have precipitated a rise in the levels of introgressive gene flow among animals. The investigation of conspecific populations at different time points may shed light on the magnitude of human-mediated introgression. We used the red junglefowl Gallus gallus, the wild ancestral form of the chicken, as our study system. As wild junglefowl and domestic chickens readily admix, conservationists fear that domestic introgression into junglefowl may compromise their wild genotype. By contrasting the whole genomes of 51 chickens with 63 junglefowl from across their natural range, we found evidence of a loss of the wild genotype across the Anthropocene. When comparing against the genomes of junglefowl from approximately a century ago using rigorous ancient-DNA protocols, we discovered that levels of domestic introgression are not equal among and within modern wild populations, with the percentage of domestic ancestry around 20-50%. We identified a number of domestication markers in which chickens are deeply differentiated from historic junglefowl regardless of breed and/or geographic provenance, with eight genes under selection. The latter are involved in pathways dealing with development, reproduction and vision. The wild genotype is an allelic reservoir that holds most of the genetic diversity of G. gallus, a species which is immensely important to human society. Our study provides fundamental genomic infrastructure to assist in efforts to prevent a further loss of the wild genotype through introgression of domestic alleles.

The herbarium of the future

The ~400 million specimens deposited across ~3000 herbaria are essential for: (i) understanding where plants have lived in the past, (ii) forecasting where they may live in the future, and (iii) delineating their conservation status. An open access 'global metaherbarium' is emerging as these specimens are digitized, mobilized, and interlinked online. This virtual biodiversity resource is attracting new users who are accelerating traditional applications of herbaria and generating basic and applied scientific innovations, including e-monographs and floras produced by diverse, interdisciplinary, and inclusive teams; robust machine-learning algorithms for species identification and phenotyping; collection and synthesis of ecological trait data at large spatiotemporal and phylogenetic scales; and exhibitions and installations that convey the beauty of plants and the value of herbaria in addressing broader societal issues.

Contrasting Responses of Alien and Ancient Forest Indicator Plant Species to Fragmentation Process in the Temperate Lowland Forests

Fragmentation is one of the major threats to biodiversity. In a fragmented landscape, forest specialists are losing suitable forest habitats with specific site and microclimate conditions, which results in their local extinction. Conversely, the invasion of alien species is facilitated by open forest areas and increased boundaries between forest fragments and adjacent land. We studied the effect of fragmentation in terms of fragment size impact on overall plant species richness and on selected ecologically important groups' richness, composition, and diversity. We surveyed vegetation in the interior of 47 fragments of various sizes and one unfragmented reference forest. Our results reveal that the effect of fragmentation is complex and differs for studied plant groups. Decreasing fragment size negatively affects the overall plant richness and richness of native and ancient forest indicator plants as well as their diversity, while the effect is positive for alien plants. The highest proportion of ancient forest indicator plant species and the lowest proportion of alien plants in the unfragmented forest underline the great conservation value of forest fragments. At the same time, our results reveal that large and diverse forest ecosystems are susceptible to biological invasions as well.

The effects of landscape change on habitat quality in arid desert areas based on future scenarios: Tarim River Basin as a case study

Human activities have caused spatiotemporal patterns of land use and land cover (LULC) change. The LULC change has directly affected habitat quality (HQ) and ecosystem functions. Assessing, simulating, and predicting spatiotemporal changes and future trends under different scenarios of LULC-influenced HQ is beneficial to land use planners and decision-makers, helping them to formulate plans in a sustainable and responsible way. This study assesses and simulates the HQ of the Tarim River Basin (TRB) using the future land use simulation model (FLUS), the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model, and partial least squares regression (PLSR). Since 2000, the TRB has experienced a declining trend in HQ from 0.449 to 0.444, especially in the lower elevations (740-2000m) and on sloped land (<10°). The decline will continue unless effective and sustainable plans are implemented to halt it. Agricultural and settlement areas have a lower HQ and a higher degree of habitat degradation than native habitats. This shows that the expansion of oasis agriculture (with an annual growth rate of 372.17 km²) and settlements (with an annual growth rate of 23.50 km²) has caused a decline in native habitat and subsequent habitat fragmentation. In other words, changes in LULC have caused a decline in the HQ. Moreover, there is a significant negative correlation between HQ and urbanization rate (p<0.01), and the PLSR also indicate that number of patches (NP), area-weighted mean fractal dimension index (FRAC_AM), percentage of landscape (PLAND), and largest patch index (LPI) were also important contributors to worsening the HQ. Therefore, the TRB urgently needs appropriate strategies to preserve its natural habitats into the future, based on the ecological priority scenario (EPS) and harmonious development scenario (HDS), which can help to maintain a high-quality habitat.

A millennium of increasing diversity of ecosystems until the mid-20th century

Land-use change is widely regarded as a simplifying and homogenising force in nature. In contrast, analysing global land-use reconstructions from the 10th to 20th centuries, we found progressive increases in the number, evenness, and diversity of ecosystems (including human-modified land-use types) present across most of the Earth's land surface. Ecosystem diversity increased more rapidly after ~1700 CE, then slowed or slightly declined (depending on the metric) following the mid-20th century acceleration of human impacts. The results also reveal increasing spatial differentiation, rather than homogenisation, in both the presence-absence and area-coverage of different ecosystem types at sub-global scales-at least, prior to the mid-20th century. Nonetheless, geographic homogenization was revealed for a subset of analyses at a global scale, reflecting the now-global presence of certain human-modified ecosystem types. Our results suggest that, while human land-use changes have caused declines in relatively undisturbed or "primary" ecosystem types, they have also driven increases in ecosystem diversity over the last millennium.

The homogenization of avian morphological and phylogenetic diversity under the global extinction crisis

Biodiversity is facing a global extinction crisis that will reduce ecological trait diversity, evolutionary history, and ultimately ecosystem functioning and services.1-4 A key challenge is understanding how species losses will impact morphological and phylogenetic diversity at global scales.5,6 Here, we test whether the loss of species threatened with extinction according to the International Union for Conservation of Nature (IUCN) leads to morphological and phylogenetic homogenization7,8 across both the whole avian class and within each biome and ecoregion globally. We use a comprehensive set of continuous morphological traits extracted from museum collections of 8,455 bird species, including geometric morphometric beak shape data,9 and sequentially remove species from those at most to least threat of extinction. We find evidence of morphological, but not phylogenetic, homogenization across the avian class, with species becoming more alike in terms of their morphology. We find that most biome and ecoregions are expected to lose morphological diversity at a greater rate than predicted by species loss alone, with the most imperiled regions found in East Asia and the Himalayan uplands and foothills. Only a small proportion of assemblages are threatened with phylogenetic homogenization, in particular parts of Indochina. Species extinctions will lead to a major loss of avian ecological strategies, but not a comparable loss of phylogenetic diversity. As the decline of species with unique traits and their replacement with more widespread generalist species continues, the protection of assemblages at most risk of morphological and phylogenetic homogenization should be a key conservation priority.

Extinction: The downsizing of morphospace

Birds with unusual traits are at elevated risk of extinction. Future avian assemblages are therefore likely to be less morphologically varied than they are today, reducing the diversity of ecosystems services they can support, and their capacity for adaptive change.

Discovery and Domestication of New Fruit Trees in the 21st Century

The exploration and use of wild plant resources goes back to our rooted history of human civilization over about 20,000 years ago, before Ancient Mesopotamia in the Valley of the Tigris and Euphrates where barley, lentil and wheat were first domesticated [...]

Long-term seed burial reveals differences in the seed-banking strategies of naturalized and invasive alien herbs

Soil seed viability and germinability dynamics can have a major influence on the establishment and spread of plants introduced beyond their native distribution range. Yet, we lack information on how temporal variability in these traits could affect the invasion process. To address this issue, we conducted an 8-year seed burial experiment examining seed viability and germinability dynamics for 21 invasive and 38 naturalized herbs in the Czech Republic. Seeds of most naturalized and invasive species persisted in the soil for several years. However, naturalized herbs exhibited greater seed longevity, on average, than invasive ones. Phylogenetic logistic models showed that seed viability (but not germinability) dynamics were significantly related to the invasion status of the study species. Seed viability declined earlier and more sharply in invasive species, and the probability of finding viable seeds of invasive species by the end of the experiment was low. Our findings suggest that invasive herbs might take advantage of high seed viability in the years immediately after dispersal, while naturalized species benefit from extended seed viability over time. These differences, however, are not sufficiently strong to explain the invasiveness of the species examined.