Background
Among sarcomas, which are rare cancers, many types are exceedingly rare; however, a definition of ultra‐rare cancers has not been established. The problem of ultra‐rare sarcomas is ...particularly relevant because they represent unique diseases, and their rarity poses major challenges for diagnosis, understanding disease biology, generating clinical evidence to support new drug development, and achieving formal authorization for novel therapies.
Methods
The Connective Tissue Oncology Society promoted a consensus effort in November 2019 to establish how to define ultra‐rare sarcomas through expert consensus and epidemiologic data and to work out a comprehensive list of these diseases. The list of ultra‐rare sarcomas was based on the 2020 World Health Organization classification, The incidence rates were estimated using the Information Network on Rare Cancers (RARECARENet) database and NETSARC (the French Sarcoma Network's clinical‐pathologic registry). Incidence rates were further validated in collaboration with the Asian cancer registries of Japan, Korea, and Taiwan.
Results
It was agreed that the best criterion for a definition of ultra‐rare sarcomas would be incidence. Ultra‐rare sarcomas were defined as those with an incidence of approximately ≤1 per 1,000,000, to include those entities whose rarity renders them extremely difficult to conduct well powered, prospective clinical studies. On the basis of this threshold, a list of ultra‐rare sarcomas was defined, which comprised 56 soft tissue sarcoma types and 21 bone sarcoma types.
conclusions
Altogether, the incidence of ultra‐rare sarcomas accounts for roughly 20% of all soft tissue and bone sarcomas. This confirms that the challenges inherent in ultra‐rare sarcomas affect large numbers of patients.
The list of ultra‐rare sarcomas, defined as those sarcomas with an incidence ≤1 per 1,000,000, comprises 56 soft tissue sarcoma and 21 bone sarcoma types. The incidence of ultra‐rare sarcomas accounts for roughly 20% of all soft tissue and bone sarcomas, confirming that challenges inherent to ultra‐rare sarcomas affect large numbers of patients.
There is broad consensus that the diversity of functional traits within species assemblages drives several ecological processes. It is also widely recognized that rare species are the first to become ...extinct following human-induced disturbances. Surprisingly, however, the functional importance of rare species is still poorly understood, particularly in tropical species-rich assemblages where the majority of species are rare, and the rate of species extinction can be high. Here, we investigated the consequences of local and regional extinctions on the functional structure of species assemblages. We used three extensive datasets (stream fish from the Brazilian Amazon, rainforest trees from French Guiana, and birds from the Australian Wet Tropics) and built an integrative measure of species rarity versus commonness, combining local abundance, geographical range, and habitat breadth. Using different scenarios of species loss, we found a disproportionate impact of rare species extinction for the three groups, with significant reductions in levels of functional richness, specialization, and originality of assemblages, which may severely undermine the integrity of ecological processes. The whole breadth of functional abilities within species assemblages, which is disproportionately supported by rare species, is certainly critical in maintaining ecosystems particularly under the ongoing rapid environmental transitions.
Because the distribution of most of the species is poorly known, conservationists use surrogates to help maximize the representation level of all species. Historically, species richness has been used ...to calculate the importance of priority areas for conservation, but several studies revealed sites with high species richness often fail to determine the smallest number of sites that will protect the highest number of species. Rarity, however, has played a prominent role in safeguarding planning units. While the performance of rarity has been previously assessed in terrestrial systems, we tested the hypothesis that rarity of a site can be used as a measure of the importance of a site to a conservation network in marine ecosystems. We used the presence data (at a 1-degree resolution) to calculate five rarity indices of fish diversity at a global extent and compared the results to those obtained by using species richness and site complementarity. Our objectives were to: (1) determine if rarity indices can be used as surrogates of fish biodiversity by representing the highest number of species in the smallest number of sites; and (2) determine if the effectiveness of these indices to represent fish biodiversity is impacted by the metric used to define rarity. Results indicate that rarity could be an effective surrogate for marine fishes, as most results showed a mean of 100% effectiveness. In the context of marine biodiversity conservation, results show that rarity indices could be considered affordable and feasible surrogates of species representation, with the most significant benefit to those areas of the world that are in most need to access alternative tools. Results also open a new area of collaboration between biogeography and marine conservation biology since planners can use biogeographical patterns of rarity to enhance the performance of the current protected area network.
The present study analyses the different binding modes that link art and luxury brands in an attempt to determine the links between the two, in particular the role of art in the creation of luxury ...uniqueness.
Four main types of relationship were identified that link luxury brands and art following an in-depth analysis of the practices of the major global luxury brands. These binding modes are: Business Collaboration, Patronage, Foundations and Artistic Mentoring.
A model is presented which assesses the relevance of each of the ‘art to luxury brand’ binding modes, in accordance with the brand's timeline and the intensity of its engagement.
The study defines a typology of the links and ties between art and luxury brands, and explains how each contributes to the brands' incomparability, designed to neutralize the risks stemming from the industrialization of luxury.
Biodiversity is undergoing unprecedented global decline. Efforts to slow this rate have focused foremost on rarer species, which are at most risk of extinction. Less interest has been paid to more ...common species, despite their greater importance in terms of ecosystem function and service provision. How rates of decline are partitioned between common and less abundant species remains unclear. Using a 30‐year data set of 144 bird species, we examined Europe‐wide trends in avian abundance and biomass. Overall, avian abundance and biomass are both declining with most of this decline being attributed to more common species, while less abundant species showed an overall increase in both abundance and biomass. If overall avian declines are mainly due to reductions in a small number of common species, conservation efforts targeted at rarer species must be better matched with efforts to increase overall bird numbers, if ecological impacts of birds are to be maintained.
Success of alien plants is often attributed to high competitive ability. However, not all aliens become dominant, and not all natives are vulnerable to competitive exclusion. Here, we quantified ...competitive outcomes and their determinants, using response‐surface experiments, in 48 pairs of native and naturalised alien annuals that are common or rare in Germany. Overall, aliens were not more competitive than natives. However, common aliens (invasive) were, despite strong limitation by intraspecific competition, more competitive than rare natives. This is because alien species had higher intrinsic growth rates than natives, and common species had higher intrinsic growth rates than rare ones. Strength of interspecific competition was not related to status or commonness. Our work highlights the importance of including commonness in understanding invasion success. It suggests that variation among species in intrinsic growth rates is more important in competitive outcomes than inter‐ or intraspecific competition, and thus contributes to invasion success and rarity.
Metacommunity ecology combines local (e.g., environmental filtering and biotic interactions) and regional (e.g., dispersal and heterogeneity) processes to understand patterns of species abundance, ...occurrence, composition, and diversity across scales of space and time. As such, it has a great potential to generalize and synthesize our understanding of many ecological problems. Here, we give an overview of how a metacommunity perspective can provide useful insights for conservation biology, which aims to understand and mitigate the effects of anthropogenic drivers that decrease population sizes, increase extinction probabilities, and threaten biodiversity. We review four general metacommunity processes—environmental filtering, biotic interactions, dispersal, and ecological drift—and discuss how key anthropogenic drivers (e.g., habitat loss and fragmentation, and nonnative species) can alter these processes. We next describe how the patterns of interest in metacommunities (abundance, occupancy, and diversity) map onto issues at the heart of conservation biology, and describe cases where conservation biology benefits by taking a scale‐explicit metacommunity perspective. We conclude with some ways forward for including metacommunity perspectives into ideas of ecosystem functioning and services, as well as approaches to habitat management, preservation, and restoration.
Metacommunity ecology combines local processes to understand patterns of species abundance, occurrence, composition, and diversity across scales of space and time. Here, we give an overview of how a metacommunity perspective can provide useful insights for conservation biology, which aims to understand and mitigate the effects of anthropogenic drivers that decrease population sizes, increase extinction probabilities, and threaten biodiversity.
1. Plant-soil feedbacks is becoming an important concept for explaining vegetation dynamics, the invasiveness of introduced exotic species in new habitats and how terrestrial ecosystems respond to ...global land use and climate change. Using a new conceptual model, we show how critical alterations in Plant-soil feedback interactions can change the assemblage of plant communities. We highlight recent advances, define terms and identify future challenges in this area of research and discuss how variations in strengths and directions of Plant-soil feedbacks can explain succession, invasion, response to climate warming and diversity-productivity relationships. 2. While there has been a rapid increase in understanding the biological, chemical and physical mechanisms and their interdependencies underlying Plant-soil feedback interactions, further progress is to be expected from applying new experimental techniques and technologies, linking empirical studies to modelling and field-based studies that can include Plant-soil feedback interactions on longer time scales that also include long-term processes such as litter decomposition and mineralization. 3. Significant progress has also been made in analysing consequences of Plant-soil feedbacks for biodiversity-functioning relationships, plant fitness and selection. 4. To further integrate Plant-soil feedbacks into ecological theory, it will be important to determine where and how observed patterns may be generalized, and how they may influence evolution. 5. Synthesis. Gaining a greater understanding of Plant-soil feedbacks and underlying mechanisms is improving our ability to predict consequences of these interactions for plant community composition and productivity under a variety of conditions. Future research will enable better prediction and mitigation of the consequences of human-induced global changes, improve efforts of restoration and conservation and promote sustainable provision of ecosystem services in a rapidly changing world.
Global abundance estimates for 9,700 bird species Callaghan, Corey T; Nakagawa, Shinichi; Cornwell, William K
Proceedings of the National Academy of Sciences - PNAS,
05/2021, Volume:
118, Issue:
21
Journal Article
Peer reviewed
Open access
Quantifying the abundance of species is essential to ecology, evolution, and conservation. The distribution of species abundances is fundamental to numerous longstanding questions in ecology, yet the ...empirical pattern at the global scale remains unresolved, with a few species' abundance well known but most poorly characterized. In large part because of heterogeneous data, few methods exist that can scale up to all species across the globe. Here, we integrate data from a suite of well-studied species with a global dataset of bird occurrences throughout the world-for 9,700 species (∼92% of all extant species)-and use missing data theory to estimate species-specific abundances with associated uncertainty. We find strong evidence that the distribution of species abundances is log left skewed: there are many rare species and comparatively few common species. By aggregating the species-level estimates, we find that there are ∼50 billion individual birds in the world at present. The global-scale abundance estimates that we provide will allow for a line of inquiry into the structure of abundance across biogeographic realms and feeding guilds as well as the consequences of life history (e.g., body size, range size) on population dynamics. Importantly, our method is repeatable and scalable: as data quantity and quality increase, our accuracy in tracking temporal changes in global biodiversity will increase. Moreover, we provide the methodological blueprint for quantifying species-specific abundance, along with uncertainty, for any organism in the world.
The number of tree species on Earth Cazzolla Gatti, Roberto; Reich, Peter B; Gamarra, Javier G P ...
Proceedings of the National Academy of Sciences - PNAS,
02/2022, Volume:
119, Issue:
6
Journal Article, Web Resource
Peer reviewed
Open access
One of the most fundamental questions in ecology is how many species inhabit the Earth. However, due to massive logistical and financial challenges and taxonomic difficulties connected to the species ...concept definition, the global numbers of species, including those of important and well-studied life forms such as trees, still remain largely unknown. Here, based on global ground-sourced data, we estimate the total tree species richness at global, continental, and biome levels. Our results indicate that there are ∼73,000 tree species globally, among which ∼9,000 tree species are yet to be discovered. Roughly 40% of undiscovered tree species are in South America. Moreover, almost one-third of all tree species to be discovered may be rare, with very low populations and limited spatial distribution (likely in remote tropical lowlands and mountains). These findings highlight the vulnerability of global forest biodiversity to anthropogenic changes in land use and climate, which disproportionately threaten rare species and thus, global tree richness.
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