57 research outputs found

    Functional traits of the world’s late Quaternary large-bodied avian and mammalian herbivores

    Full text link
    Prehistoric and recent extinctions of large-bodied terrestrial herbivores had significant and lasting impacts on Earth’s ecosystems due to the loss of their distinct trait combinations. The world’s surviving large-bodied avian and mammalian herbivores remain among the most threatened taxa. As such, a greater understanding of the ecological impacts of large herbivore losses is increasingly important. However, comprehensive and ecologically-relevant trait datasets for extinct and extant herbivores are lacking. Here, we present HerbiTraits, a comprehensive functional trait dataset for all late Quaternary terrestrial avian and mammalian herbivores ≄10 kg (545 species). HerbiTraits includes key traits that influence how herbivores interact with ecosystems, namely body mass, diet, fermentation type, habitat use, and limb morphology. Trait data were compiled from 557 sources and comprise the best available knowledge on late Quaternary large-bodied herbivores. HerbiTraits provides a tool for the analysis of herbivore functional diversity both past and present and its effects on Earth’s ecosystems

    Science for a wilder Anthropocene: synthesis and future directions for trophic rewilding research

    Get PDF
    Trophic rewilding is an ecological restoration strategy that uses species introductions to restore top-down trophic interactions and associated trophic cascades to promote self-regulating biodiverse ecosystems. Given the importance of large animals in trophic cascades and their widespread losses and resulting trophic downgrading, it often focuses on restoring functional megafaunas. Trophic rewilding is increasingly being implemented for conservation, but remains controversial. Here, we provide a synthesis of its current scientific basis, highlighting trophic cascades as the key conceptual framework, discussing the main lessons learned from ongoing rewilding projects, systematically reviewing the current literature, and highlighting unintentional rewilding and spontaneous wildlife comebacks as underused sources of information. Together, these lines of evidence show that trophic cascades may be restored via species reintroductions and ecological replacements. It is clear, however, that megafauna effects may be affected by poorly understood trophic complexity effects and interactions with landscape settings, human activities, and other factors. Unfortunately, empirical research on trophic rewilding is still rare, fragmented, and geographically biased, with the literature dominated by essays and opinion pieces. We highlight the need for applied programs to include hypothesis testing and science-based monitoring, and outline priorities for future research, notably assessing the role of trophic complexity, interplay with landscape settings, land use, and climate change, as well as developing the global scope for rewilding and tools to optimize benefits and reduce human–wildlife conflicts. Finally, we recommend developing a decision framework for species selection, building on functional and phylogenetic information and with attention to the potential contribution from synthetic biology

    A critical perspective on the concept of biocultural diversity and its emerging role in nature and heritage conservation

    Get PDF
    The continuing losses of biodiversity around the world remain problematic for nature conservation. A fundamental issue that has triggered debates in nature conservation is the relationship between human culture, heritage and history, and nature expressed as ecology or biodiversity. Traditionally, nature conservation has been pursued separately from aspects of cultural heritage; a situation which seems perplexing when we consider the importance of traditional management in the maintenance of biodiversity in many areas now “protected” for nature. To address these broad issues, fundamental to future landscape sustainability, we need to have clear definitions of concepts and terms. This paper considers the historical development of the key concepts that frame biocultural diversity and the paradigms relating to biocultural assets or eco-cultural landscapes. This is pertinent to both researchers and to practitioners or policymakers, and we suggest ways biocultural diversity can improve global conservation efforts

    Everything under control? Comparing Knepp Estate rewilding project with ‘traditional’ nature conservation

    Get PDF
    ‘Rewilding’ is an increasingly prominent concept in conservation, but one that has attracted controversy. Debate frequently focuses on human ‘control’ over nature. ‘Traditional’ conservation has been presented as involving ‘high control,’ and rewilding as ‘low control.’ Opposition to rewilding often stems from a perceived lack of control and associated perception of increased risk and uncertainty. This paper explores the concept of control in conservation. I identify multiple dimensions of control (‘stabilisation’, ‘location’, ‘prediction’ and ‘outputs’), illustrating that control is not a simple, linear concept. I compare two ethnographic case studies: the Sussex Wildlife Trust’s Old Lodge nature reserve; and Knepp Estate, one of the most influential rewilding projects in the UK. I use them to test assertions made about control in ‘traditional’ conservation and ‘rewilding’. I outline how Old Lodge does not exert precise control in all respects, but involves elements of uncertainty and negotiation. I describe how Knepp’s model of rewilding reduces control in some dimensions but potentially increases it in others. I conclude that, while Knepp’s rewilding does represent a significant conceptual departure from ‘traditional’ conservation, it should not be characterised as an approach that reduces control in a simplistic way. Based on this analysis, I argue that reduction of control does not necessarily underpin the concept of rewilding. Rather, there is interplay between different control dimensions that combine to form multiple ‘configurations of control.’ Using a framework of ‘configurations of control’, debate about the place of rewilding in conservation can become less polarised, and instead involve an active discussion of what configuration of control is desired. This analysis has the potential to increase understanding of rewilding projects as part of plural conservation strategies, in the UK and globally

    Rewilding complex ecosystems

    Get PDF
    BACKGROUND: Rapid global change is creating fundamental challenges for the persistence of natural ecosystems and their biodiversity. Conservation efforts aimed at the protection of landscapes have had mixed success, and there is an increasing awareness that the long-term protection of biodiversity requires inclusion of flexible restoration along with protection. Rewilding is one such approach that has been both promoted and criticized in recent years. Proponents emphasize the potential of rewilding to tap opportunities for restoration while creating benefits for both ecosystems and societies. Critics discuss the lack of a consistent definition of rewilding and insufficient knowledge about its potential outcomes. Other criticisms arise from the mistaken notion that rewilding actions are planned without considering societal acceptability and benefits. Here, we present a framework for rewilding actions that can serve as a guideline for researchers and managers. The framework is applicable to a variety of rewilding approaches, ranging from passive to trophic rewilding, and aims to promote beneficial interactions between society and nature. ADVANCES: The concept of rewilding has evolved from its initial emphasis on protecting large, connected areas for large carnivore conservation to a process-oriented, dynamic approach. On the basis of concepts from resilience and complexity theory of social-ecological systems, we identify trophic complexity, stochastic disturbances, and dispersal as three critical components of natural ecosystem dynamics. We propose that the restoration of these processes, and their interactions, can lead to increased self-sustainability of ecosystems and should be at the core of rewilding actions. Building on these concepts, we develop a framework to design and evaluate rewilding plans. Alongside ecological restoration goals, our framework emphasizes people’s perceptions and experiences of wildness and the regulating and material contributions from restoring nature. These societal aspects are important outcomes and may be critical factors for the success of rewilding initiatives (see the figure). We further identify current societal constraints on rewilding and suggest actions to mitigate them. OUTLOOK: The concept of rewilding challenges us to rethink the way we manage nature and to broaden our vision about how nature will respond to changes that society brings, both intentionally and unintentionally. The effects of rewilding actions will be specific to each ecosystem, and thus a deep understanding of the processes that shape ecosystems is critical to anticipate these effects and to take appropriate management actions. In addition, the decision of whether a rewilding approach is desirable should consider stakeholders’ needs and expectations. To this end, structured restoration planning—based on participatory processes involving researchers, managers, and stakeholders—that includes monitoring and adaptive management can be used. With the recent designation of 2021–2030 as the “decade of ecosystem restoration” by the United Nations General Assembly, policy- and decision-makers could push rewilding topics to the forefront of discussions about how to reach post-2020 biodiversity goals

    Saving the world’s terrestrial megafauna

    Get PDF
    From the late Pleistocene to the Holocene, and now the so called Anthropocene, humans have been driving an ongoing series of species declines and extinctions (Dirzo et al. 2014). Large-bodied mammals are typically at a higher risk of extinction than smaller ones (Cardillo et al. 2005). However, in some circumstances terrestrial megafauna populations have been able to recover some of their lost numbers due to strong conservation and political commitment, and human cultural changes (Chapron et al. 2014). Indeed many would be in considerably worse predicaments in the absence of conservation action (Hoffmann et al. 2015). Nevertheless, most mammalian megafauna face dramatic range contractions and population declines. In fact, 59% of the world’s largest carnivores (≄ 15 kg, n = 27) and 60% of the world’s largest herbivores (≄ 100 kg, n = 74) are classified as threatened with extinction on the International Union for the Conservation of Nature (IUCN) Red List (supplemental table S1 and S2). This situation is particularly dire in sub-Saharan Africa and Southeast Asia, home to the greatest diversity of extant megafauna (figure 1). Species at risk of extinction include some of the world’s most iconic animals—such as gorillas, rhinos, and big cats (figure 2 top row)—and, unfortunately, they are vanishing just as science is discovering their essential ecological roles (Estes et al. 2011). Here, our objectives are to raise awareness of how these megafauna are imperiled (species in supplemental table S1 and S2) and to stimulate broad interest in developing specific recommendations and concerted action to conserve them

    General dental practices with and without a dental therapist: a survey of appointment activities and patient satisfaction with their care.

    Get PDF
    Introduction Policy changes regarding the role of Dental Hygienist-Therapists (DTs) have been implemented in recent years with a view to promoting delivery of oral health-care through a more preventive-focused, team work approach. Aims To explore i) treatments led by dentists and DTs, and ii) patients' satisfaction with the care they received. Materials and methods Six case-studies of general dental practices in Wales, UK: three with, and three without a DT. For each participant, a patient-satisfaction questionnaire and a staff-member-completed appointment record form were completed. We sought to recruit 150 patients seeing a dentist and 100 patients seeing a DT, per case-study practice. Results 1,224 patients were recruited in total (314 DT and 910 dentist appointments). Preventive work accounted for nearly half of all treatments. Dentists, in practices with a DT, undertook significantly less preventive and restorative work, and significantly more extractions and advanced treatment (p <0.005, χÂČ = 15.352). Patient satisfaction and confidence in dentists' or DTs' ability was uniformly high (97% and 99% each group respectively). Conclusion Practices with DTs provided a more preventive-focused approach to oral health-care delivery; dentists in these practices performed more complex work. Positive patient satisfaction and confidence in practitioners' ability suggest patient acceptability of a preventive model

    Historical biogeography of the leopard (Panthera pardus) and its extinct Eurasian populations

    Get PDF
    Background: Resolving the historical biogeography of the leopard (Panthera pardus) is a complex issue, because patterns inferred from fossils and from molecular data lack congruence. Fossil evidence supports an African origin, and suggests that leopards were already present in Eurasia during the Early Pleistocene. Analysis of DNA sequences however, suggests a more recent, Middle Pleistocene shared ancestry of Asian and African leopards. These contrasting patterns led researchers to propose a two-stage hypothesis of leopard dispersal out of Africa: an initial Early Pleistocene colonisation of Asia and a subsequent replacement by a second colonisation wave during the Middle Pleistocene. The status of Late Pleistocene European leopards within this scenario is unclear: were these populations remnants of the first dispersal, or do the last surviving European leopards share more recent ancestry with their African counterparts? Results: In this study, we generate and analyse mitogenome sequences from historical samples that span the entire modern leopard distribution, as well as from Late Pleistocene remains. We find a deep bifurcation between African and Eurasian mitochondrial lineages (~ 710 Ka), with the European ancient samples as sister to all Asian lineages (~ 483 Ka). The modern and historical mainland Asian lineages share a relatively recent common ancestor (~ 122 Ka), and we find one Javan sample nested within these. Conclusions: The phylogenetic placement of the ancient European leopard as sister group to Asian leopards suggests that these populations originate from the same out-of-Africa dispersal which founded the Asian lineages. The coalescence time found for the mitochondrial lineages aligns well with the earliest undisputed fossils in Eurasia, and thus encourages a re-evaluation of the identification of the much older putative leopard fossils from the region. The relatively recent ancestry of all mainland Asian leopard lineages suggests that these populations underwent a severe population bottleneck during the Pleistocene. Finally, although only based on a single sample, the unexpected phylogenetic placement of the Javan leopard could be interpreted as evidence for exchange of mitochondrial lineages between Java and mainland Asia, calling for further investigation into the evolutionary history of this subspecies

    Human Factors Considerations for System Safety

    No full text
    • 

    corecore