Ongoing Extinction Research Articles

Motivating government on threatened species through electoral systems

AbstractMany of the proposed solutions to the global biodiversity crisis rely on national governments to act. The conservation movement needs to motivate governments or face an ongoing extinction crisis. Here we explore how linking biodiversity to electoral systems may assist in motivating government action. Using Australia as a case study, we analyze the intersection of 151 electoral districts and 1651 threatened species. We show all districts contain at least 14 threatened species. Half of the species analyzed (n = 801, 49%) are confined to one district (n = 44), with 1345 (81%) species intersecting with less than five. This geographical information shows that alongside local social and economic issues, the threatened species crisis can be made relevant to all Australian elected representatives. Locally relevant information can encourage integration of species needs into the scope of political representation. As such, linking biodiversity to political geography offers a potential pathway to creating transformative change.

Global mismatches between threat mapping research effort and the potential of threat abatement actions to reduce extinction risk.

Threat mapping is a necessary tool for identifying and abating direct threats to species in the ongoing extinction crisis. There are known gaps in the threat mapping literature for particular threats and geographic locations, and it remains unclear if the distribution of research effort is appropriately targeted relative to conservation need. We aimed to determine the drivers of threat mapping research effort and to quantify gaps that, if filled, could inform actions with the highest potential to reduce species' extinction risk. We used a negative binomial generalized linear model to analyze research effort as a function of threat abatement potential (quantified as the potential reduction in species extinction risk from abating threats), species richness, land area, and human pressure. The model showed that threat mapping research effort increased by 1.1 to 1.2 times per standardized unit change in threat abatement potential. However, species richness and land area were stronger predictors of research effort overall. The greatest areas of mismatch between research effort and threat abatement potential, receiving disproportionately low research effort, were related to the threats to species of agriculture, aquaculture, and biological resource use across the tropical regions of the Americas, Asia, and Madagascar. Conversely, the threat of linear infrastructure (e.g., roads and rails) across regions, the threat of biological resource use (e.g., hunting or collection) in sub-Saharan Africa, and overall threats in North America and Europe all received disproportionately high research effort. We discuss the range of methodological and sociopolitical factors that may be behind the overall trends and specific areas of mismatch we found. We urge a stronger emphasis on targeting research effort toward those threats and geographic locations where threat abatement activities could make the greatest contribution to reducing global species extinction risk.

The paradox of searching efficiency or why are violent population cycles so uncommon in terrestrial ecosystem

The searching efficiency of predators depends on the balance between the adaptations of the predator and the counter‐adaptations of the prey. In this evolutionary race, the prey should normally have the upper hand, as it can perform tradeoffs between efficiency in resource use and ability to avoid predators. In terrestrial predator–herbivore systems, however, the huge difference in food quality between prey and predators seems to give predators an advantage. In productive terrestrial ecosystems, predators thus chronically overexploit herbivores, i.e. regulate them at densities far below the point of maximum sustainable yield. Assuming type II functional response, this should result in violent limit cycle dynamics. In reality, however, such cycles are only common at high latitudes, whereas the herbivory‐based food webs of species‐rich ecosystems at middle and low latitudes are characterized by asymptotic dynamics, where numerical changes only occur in response to external forcing. One way or another, diversity thus seems to beget stability in terrestrial grazing webs. We propose that strong, donor‐controlled energy flows from the detritus web and directly from plants to predators are the key for the prevalence of asymptotic dynamics at middle and low latitudes. These flows support generalists with type III functional response and, therefore, a capacity to curb budding outbreaks at an early stage. The ongoing extinction wave could critically weaken these stabilizing interactions, which could destabilize currently stable food webs. and result in violent limit cycle dynamics in ecosystems, where the dominating species have evolved under asymptotic dynamics. This could cause secondary extinctions and inflict large economic losses.Keywords: extinction, food webs, limit cycles, overexploitation, searching efficiency, stability

Effects of subpopulation extinction on effective size (Ne) of metapopulations

Population extinction is ubiquitous in all taxa. Such extirpations can reduce intraspecific diversity, but the extent to which genetic diversity of surviving populations are affected remains largely unclear. A key concept in this context is the effective population size (Ne), which quantifies the rate at which genetic diversity within populations is lost. Ne was developed for single, isolated populations while many natural populations are instead connected to other populations via gene flow. Recent analytical approaches and software permit modelling of Ne of interconnected populations (metapopulations). Here, we apply such tools to investigate how extinction of subpopulations affects Ne of the metapopulation (NeMeta) and of separate surviving subpopulations (NeRx) under different rates and patterns of genetic exchange between subpopulations. We assess extinction effects before and at migration-drift equilibrium. We find that the effect of extinction on NeMeta increases with reduced connectivity, suggesting that stepping stone models of migration are more impacted than island-migration models when the same number of subpopulations are lost. Furthermore, in stepping stone models, after extinction and before a new equilibrium has been reached, NeRx can vary drastically among surviving subpopulations and depends on their initial spatial position relative to extinct ones. Our results demonstrate that extinctions can have far more complex effects on the retention of intraspecific diversity than typically recognized. Metapopulation dynamics need heightened consideration in sustainable management and conservation, e.g., in monitoring genetic diversity, and are relevant to a wide range of species in the ongoing extinction crisis.

Understanding local plant extinctions before it is too late: bridging evolutionary genomics with global ecology.

Understanding evolutionary genomic and population processes within a species range is key to anticipating the extinction of plant species before it is too late. However, most models of biodiversity risk under global change do not account for the genetic variation and local adaptation of different populations. Population diversity is critical to understanding extinction because different populations may be more or less susceptible to global change and, if lost, would reduce the total diversity within a species. Two new modeling frameworks advance our understanding of extinction from a population and evolutionary angle: Rapid climate change-driven disruptions in population adaptation are predicted from associations between genomes and local climates. Furthermore, losses of population diversity from global land-use transformations are estimated by scaling relationships of species' genomic diversity with habitat area. Overall, these global eco-evolutionary methods advance the predictability - and possibly the preventability - of the ongoing extinction of plant species.

The Revolution Will Be Danced

The Revolution Will Be Danced

Threat belief determines the degree of costly safety behavior: Assessing rule-based generalization of safety behavior with a dimensional measure of avoidance

Excessive generalization of safety behavior to innocuous stimuli that resemble a feared stimulus is oftentimes pathological especially with inflicted impairments. Safety behavior is conventionally assessed dichotomously, requiring multiple presentations of each test stimulus for assessing the proportion of safety behavior executed. Thus, the generalization gradient confounds with ongoing extinction learning during non-reinforced test trials. The present study employed a recently developed dimensional measure of avoidance to examine the extent of safety behavior generalization. We found that a dimensional measure of avoidance was able to assess the generalization gradients of safety behavior even when each test stimulus was presented once, thus minimizing the effect of ongoing extinction learning. Of equal importance is whether higher-order cognitive processes shape generalization of safety behavior. We found a range of distinct generalization gradients in safety behavior, which were highly consistent with participants’ verbally reported relational rules. This rule-based generalization parallels to how clinically anxious individuals develop different threat beliefs after trauma exposure, and models how these distinct threat beliefs determine the extent of safety behavior engagement.

Homogenized Phylogeographic Structure across the Indo-Burma Ranges of a Large Monoecious Fig, Ficus altissima Blume

As well as bountiful natural resources, the Indo-Burma biodiversity hotspot features high rates of habitat destruction and fragmentation due to increasing human activity; however, most of the Indo-Burma species are poorly studied. The exploration of plants closely associated with human activity will further assist us to understand our influence in the context of the ongoing extinction events in the Anthropocene. This study, based on widely and intensively sampled F. altissima across Indo-Burma and the adjacent south China ranges, using both the chloroplast psbA-trnH spacer and sixteen newly developed nuclear microsatellite markers (nSSRs), aims to explore its spatial genetic structure. The results indicated low chloroplast haplotype diversity and a moderate level of nuclear genetic diversity. Although limited seed flow was revealed by psbA-trnH, no discernible phylogeographic structure was shown due to the low resolution of cpDNA markers and dominance of an ancestral haplotype. From the nSSRs data set, phylogeographic structure was homogenized, most likely due to extensive pollen flow mediated by pollinating fig wasps. Additionally, human cultivation and human-mediated transplanting further confounded the analyses of population structure. No geographic barriers are evident across the large study range, with F. altissima constituting a single population, and extensive human cultivation is likely to have had beneficial consequences for protecting the genetic diversity of F. altissima.

Different extinction debts among plants and arthropods after loss of grassland amount and connectivity

A decrease in habitat amount and connectivity causes immediate or delayed species extinctions in transformed landscapes due to reduced functional connections among populations and altered environmental conditions. We assessed the effects of present and historical grassland amount and connectivity as well as local habitat factors typical of the present landscape on the current species richness of grassland specialist and generalist plants and arthropods in grassland fragments. We surveyed herbaceous plants, ants, orthopterans, true bugs and rove beetles in 60 dry grassland fragments in Hungary. We recorded the area of the focal grassland, the slope and the cover of woody vegetation. By using habitat maps of the present and historical landscape, we calculated grassland amount and connectivity for four time periods covering 158 years (1858–2016). We found evidence for an unpaid extinction debt in specialist plants, suggesting that they have not come to equilibrium with the grassland amount and connectivity of the present landscape yet. This localised and typically long-lived group responded slowly to the landscape changes. Specialist arthropod taxa with short generation times responded much faster to habitat loss than plants and did not show an extinction debt. Generalist plants and animals adapted to a wide range of habitats were affected by the landscape-scale decline of grassland habitats. Despite decreased habitat connectivity, grassland fragments with dry environmental conditions and high environmental heterogeneity can sustain specialist plants in transformed landscapes. Unpaid extinction debt should be considered an early warning signal: Restoration of grassland connectivity is necessary to halt ongoing extinction processes.

What Environmental and Personal Factors Determine the Implementation Intensity of Nature-Based Education in Elementary and Lower-Secondary Schools?

As society becomes increasingly urbanized, children are becoming much less likely to experience nature. This progressive disengagement from the natural world, often termed the ‘extinction of experience’, has been viewed both as a key public health issue and one of the most fundamental obstacles to halting global environmental degradation. School education has an important role in mitigating and reversing the ongoing extinction of experience. Here, we examine the role of several factors that determine the implementation intensities of nature-based education by science teachers in the classrooms of both primary and secondary schools. We performed a large-scale questionnaire survey comprising 363 elementary and 259 lower-secondary schoolteachers. Several factors predicted the implementation intensity of nature-based education in schools. The most important predictor was teachers’ levels of nature-relatedness, with nature-orientated teachers being more likely to provide nature-based education in their classes. Levels of teachers’ ecological knowledge, frequency of childhood nature experiences, and greenness within the school were also positively associated with the implementation intensity of education. Our results suggest that, to promote nature-based education in schools, it is important to increase schoolteachers’ nature-relatedness and ecological knowledge, as well as to provide more green spaces within schools.

Becoming society again: Reimagining new social contracts through Scandinavian creation theology

AbstractThis article focuses on bodily care as the basis of economy. Drawing on Luther and Scandinavian Creation Theology, with an emphasis on shared situatedness and society, I discuss contemporary threats to welfare states. Conservative arguments in favor of family and small communities, combined with charity, provide a cultural/religious alibi for a global “neoliberalism,” where citizens are replaced by customers, and where power and resources from professions are transferred to controllers, due to the logic of NPM. In a critical discussion with Hannah Arendt, I argue that we need a politics that reinforce and develop new social contracts, national as well as international, based on an inclusive demos. A pre‐political Lutheran ethos can give inspiration to act for the common good, transcending any homogenous ethnos. The local and national are crucial for sustaining body and mind. However, this is increasingly combined with global and planetary entanglements. Interdependency reveals itself as planetary, where disappearing rain forests, melting icebergs, and the ongoing extinction of species are threats to our shared future. Therefore, rather than emphasizing the individual as a consumer on a global market with neutral administrators administering control and obedience, new kinds of contracts are needed. Core values of the pre‐political, such as care for bodily life and minds, may, in collaboration with national and international political assemblies, develop a planetary consciousness able to act for the common good, for a global demos with structures of solidarity.

Associative learning and extinction of conditioned threat predictors across sensory modalities

The formation and persistence of negative pain-related expectations by classical conditioning remain incompletely understood. We elucidated behavioural and neural correlates involved in the acquisition and extinction of negative expectations towards different threats across sensory modalities. In two complementary functional magnetic resonance imaging studies in healthy humans, differential conditioning paradigms combined interoceptive visceral pain with somatic pain (study 1) and aversive tone (study 2) as exteroceptive threats. Conditioned responses to interoceptive threat predictors were enhanced in both studies, consistently involving the insula and cingulate cortex. Interoceptive threats had a greater impact on extinction efficacy, resulting in disruption of ongoing extinction (study 1), and selective resurgence of interoceptive CS-US associations after complete extinction (study 2). In the face of multiple threats, we preferentially learn, store, and remember interoceptive danger signals. As key mediators of nocebo effects, conditioned responses may be particularly relevant to clinical conditions involving disturbed interoception and chronic visceral pain.

Towards quantifying the mass extinction debt of the Anthropocene.

To make sense of our present biodiversity crises, the modern rate of species extinctions is commonly compared to a benchmark, or 'background,' rate derived from the fossil record. These estimates are critical for bounding the scale of modern diversity loss, but are yet to fully account for the fundamental structure of extinction rates through time. Namely, a substantial fraction of extinctions within the fossil record occurs within relatively short-lived extinction pulses, and not during intervals characterized by background rates of extinction. Accordingly, it is more appropriate to compare the modern event to these pulses than to the long-term average rate. Unfortunately, neither the duration of extinction pulses in the geological record nor the ultimate magnitude of the extinction pulse today is resolved, making assessments of their relative sizes difficult. In addition, the common metric used to compare current and past extinction rates does not correct for large differences in observation duration. Here, we propose a new predictive metric that may be used to ascertain the ultimate extent of the ongoing extinction threat, building on the observation that extinction magnitude in the marine fossil record is correlated to the magnitude of sedimentary turnover. Thus, we propose that the ultimate number of species destined for extinction today can be predicted by way of a quantitative appraisal of humanity's modification of ecosystems as recorded in sediments-that is, by comparing our future rock record with that of the past. The ubiquity of habitat disruption worldwide suggests that a profound mass extinction debt exists today, but one that might yet be averted by preserving and restoring ecosystems and their geological traces.

Analogies and lessons from COVID-19 for tackling the extinction and climate crises

As environmental scientists working in countries whose COVID-linked deaths already exceed their military casualties from all campaigns since 1945, we believe there are significant messages from the handling of this horrific disease for efforts addressing the enormous challenges posed by the ongoing extinction and climate emergencies.

Meaning at the End of Meaning: Nihilism, Great Nonsense, and Praxis in the Shadow of Extinction

ABSTRACT I suggest in this essay that the responses to the coronavirus pandemic by the North Atlantic elite ought to be accounted in part to the circulation of nihilism as a structure of feeling under late capitalism. I then pose the question, how ought we think of meaning and meaning making under the shadow of ongoing extinction?

Sons and Daughters of the Bear Mother: On Humanimal Culture

This essay investigates the ambiguous relationship between humans and bears, especially in light of the catastrophic fate of the latter in the Anthropocene. Their demise correlates to the loss of any cultural, political, and economic sense of our kinship with them. The consequences of this growing ontological gap include the ongoing extinction of "humanimal culture."

Current status of liver transplantation in Europe

Liver transplantation (LT) in Europe became an established life-saving treatment for patients with end-stage liver disease, hepatocellular carcinoma, and acute liver conditions with life-threatening hepatic dysfunction. Although there are substantial disparities in donation and transplant rates among European countries, LT can be offered to almost every European citizen today. In order to maximize the LT benefit beyond national levels, many countries cooperate within transnational organizations including Eurotransplant, Scandiatransplant, and Southern Alliance for Transplantation. In the majority of European countries, liver allocation is based on the Model for End-Stage Liver Disease (MELD). Similar to North America, the ongoing extinction of hepatitis C and increase of non-alcoholic steatohepatitis are also a hallmark of change in LT indications in Europe. Apart from Turkey, the organ pool for LT in European countries is mainly based on organs from donors after brain death, although some countries retrieve a substantial proportion of organs from donors after circulatory death. According to the 2018 report of the European Liver Transplant Registry, 146,762 LT have been performed in Europe until 2016. In the most recent period, LT in Europe achieved respectable 1- and 5-year overall survival rates of 86% and 74%.

The inequalities of the extinction of experience: The role of personal characteristics and species traits in the distribution of people–plant interactions in Japan

AbstractThere is concern about the increasing loss of people's direct interactions with fauna and flora. This extinction of experience has many potential far‐reaching implications for both biodiversity and humans, including the decrease of public support for conservation issues and a reduction in the health benefits that humans experience when interacting with nature. However, knowledge of how experiences with biodiversity are distributed among different sectors of society and the key drivers of this distribution remains poor. Here, we report on the results of a nation‐wide online survey in Japan in which we explored the extent, distribution, and drivers of participant's direct experiences with wild flowering plants. Participants were asked to provide information on their sociodemographics, orientation toward nature, childhood residential environment, and whether they had experienced each of 21 wild flowering plant species. The reported number of wild flowering plant species that participants had experienced varied greatly. Older and female participants and those with childhoods in rural areas and with a greater orientation toward nature experienced a significantly higher number of interactions with flowering plant species. Plant species that prefer roadside environments (compared to grassland/farmland and forest‐dependent species) and are not on the Red List were likely to be experienced by participants. This novel study provides unique information about the interactions of people and the wildlife around them. Such information is crucial for the development of policies and strategies targeted to reduce the ongoing extinction of experience and its negative consequences.

Preserving the tree of life of the fish family Cyprinidae in Africa in the face of the ongoing extinction crisis 1.

Our understanding of how the phylogenetic tree of fishes might be affected by the ongoing extinction risk is poor. This is due to the unavailability of comprehensive DNA data, especially for many African lineages. In addition, the ongoing taxonomic confusion within some lineages, e.g., Cyprinidae, makes it difficult to contribute to the debate on how the fish tree of life might be shaped by extinction. Here, we combine COI sequences and taxonomic information to assemble a fully sampled phylogeny of the African Cyprinidae and investigate whether we might lose more phylogenetic diversity (PD) than expected if currently threatened species go extinct. We found evidence for phylogenetic signal in extinction risk, suggesting that some lineages might be at higher risk than others. Based on simulated extinctions, we found that the loss of all threatened species, which approximates 37% of total PD, would lead to a greater loss of PD than expected, although highly evolutionarily distinct species are not particularly at risk. Pending the reconstruction of an improved multi-gene phylogeny, our results suggest that prioritizing high-EDGE species (evolutionary distinct and globally endangered species) in conservation programmes, particularly in some geographic regions, would contribute significantly to safeguarding the tree of life of the African Cyprinidae.

What are the drivers of and barriers to children’s direct experiences of nature?

In our increasingly urbanised world, children are becoming disconnected from the natural world. This progressive separation of humans from nature, “extinction of experience,” is viewed both as a major public health issue and as one of the fundamental obstacles to halting global biodiversity loss. Thus, it has become increasingly important to understand what drives and limits children’s direct experiences of nature. We administered a large-scale questionnaire to 5801 children from 45 elementary schools in Tochigi, central Japan. Children were asked to provide information on frequency of nature experiences, extent of nature relatedness, time pressure, inclination towards screen-based media, and their family members’ attitudes towards nature-based activities (family members’ nature orientation). We also calculated the proportion of urbanised areas within a 1-km radius of each school. Results showed that the frequency of children’s nature experiences was significantly positively associated with individual nature relatedness and family members’ nature orientation; time pressure and inclination towards screen-based media were not significantly negatively related to children’s frequency of nature experiences. Degree of urbanisation had significant negative influences on the frequency of direct experiences of nature. Male children participated in nature-based activities more frequently. Overall, our study demonstrates that children’s direct engagement with neighbourhood nature is shaped by multiple opportunity- and orientation-related factors, which has important policy implications as it implies that there can be no simple, straightforward way to promote children’s nature experiences. Thus, to minimise the ongoing extinction of experience, a variety of different and complementary approaches must be taken.