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Conditions capable of supporting multicellular life are predicted to continue for another billion years, but humans will inevitably become extinct within several million years. We explore the paradox of a habitable planet devoid of people, and consider how to prioritise our actions to maximise life after we are gone.

Habitat modification by fire and habitat loss via anthropogenic vegetation clearance and fragmentation both impact animal populations. Yet, there has been limited investigation as to whether animals that decline under one of these types of habitat change also decline under the other, and how their cumulative impacts affect the status of species and communities. Using a ~400-year chronosequence in the world's largest extant temperate woodland in south-western Australia, we examine how time since fire affects bird community richness, reporting rates and composition, and whether taxa grouped on the basis of responses to vegetation clearance and fragmentation in an adjoining agricultural landscape are associated with either recently-burnt or long-unburnt woodlands. Consistent with substantial changes in vegetation composition and structure after fire in obligate-seeder eucalypt woodlands, woodland bird communities were strongly affected by fire. Species richness and total reporting rates increased with time since fire, and community composition changed across the entire multi-century span of the chronosequence. Woodland birds most negatively impacted by vegetation clearance and fragmentation were strongly associated with long-unburnt woodlands. In a regional south-western Australian context, where extensive vegetation clearance has substantially reduced the range and populations of many woodland bird species, the ability of remaining unfragmented woodlands to support populations of these species will be strongly contingent on appropriate fire management. Specifically, as stand-replacement fires have affected 25–30% of extant woodland over recent decades, management to limit the extent of fire in remaining long-unburnt woodlands would appear a priority for conservation of woodland bird diversity.

The recent capture and removal to captivity of the first Nicobar Pigeon in Australia on the basis of biosecurity concerns, provides a compelling opportunity to examine how we manage species that naturally disperse to new territories. With the spectre of increasing climate change there is an increasing recognition of the need for species to expand or shift their ranges as part of natural adaptation. The occurrence of vagrants is a natural phenomenon that may be increasing as a result of climate change and other disturbances, but self-introduced organisms are known world-wide in multiple taxa. Although most vagrants are short-lived and of little lasting ecological consequence, some represent the forerunners of climate adaptation—individuals best placed to found new populations beyond their previous range. In contrast to invasive species for which policies and legislative instruments are commonplace (including watch lists of the world's worst invaders), policy makers have failed to consider the inherent dynamism of distributional ranges and the important role of vagrants as first responders to environmental change. The application of ad-hoc policies considering individual vagrants as a biosecurity risk is ill-informed, ecologically indefensible, and potentially counter-productive. We articulate the need for a new framework to consider vagrants as climate refugees and challenge conservation managers and on-ground practitioners to take active roles in determining how they are both viewed and managed.

Managing and restoring connectivity that enables wildlife movement through landscapes is the primary approach to reduce harmful effects of habitat loss and fragmentation. Improved connectivity is also increasingly invoked as a strategy to mitigate negative impacts of climate change by enabling species to track preferred environments and maintain evolutionary processes. Although initiatives to improve connectivity using restoration are becoming commonplace, we do not know how successful these actions are, nor which mechanisms underlie biotic responses. Most ecological monitoring focuses on site condition or quality rather than those landscape-scale processes that connectivity is intended to facilitate. To assess biodiversity responses to connectivity initiatives, we argue that new monitoring approaches are needed that distinguish the roles of connectivity restoration from those of habitat augmentation or improvement. To address this critical gap, we developed a conceptual model of the hypothesised roles of connectivity in complex landscapes and a linked framework to guide design of connectivity monitoring approaches in an adaptive management context. We demonstrate that integrated monitoring approaches using complementary methods are essential to reveal whether long-term landscape-scale goals are being achieved, and to determine whether connectivity management and restoration are the mechanisms responsible. We summarize a real-world example of applying our approach to assist government develop a monitoring plan for a large-scale connectivity conservation initiative in the Australian Capital Territory. As well as highlighting the utility of the framework to help managers make informed choices about monitoring, this example illustrates the difficulties of convincing funding bodies to include monitoring in project budgets and the questions more likely to be answered with limited funds. Synthesis and applications. Implementing an effective strategy to monitor connectivity conservation initiatives necessarily involves more work but we argue it is an essential investment rather than an additional cost. By optimizing allocation of limited monitoring resources, we can more effectively implement management that improves functional connectivity, and understand how changing connectivity affects population persistence.

Neuroimaging studies have found distinct patterns of response to different categories of scenes. However, the relative importance of low-level image properties in generating these response patterns is not fully understood. To address this issue, we directly manipulated the low level properties of scenes in a way that preserved the ability to perceive the category. We then measured the effect of these manipulations on category-selective patterns of fMRI response in the PPA, RSC and OPA. In Experiment 1, a horizontal-pass or vertical-pass orientation filter was applied to images of indoor and natural scenes. The image filter did not have a large effect on the patterns of response. For example, vertical- and horizontal-pass filtered indoor images generated similar patterns of response. Similarly, vertical- and horizontal-pass filtered natural scenes generated similar patterns of response. In Experiment 2, low-pass or high-pass spatial frequency filters were applied to the images. We found that image filter had a marked effect on the patterns of response in scene-selective regions. For example, low-pass indoor images generated similar patterns of response to low-pass natural images. The effect of filter varied across different scene-selective regions, suggesting differences in the way that scenes are represented in these regions. These results indicate that patterns of response in scene-selective regions are sensitive to the low-level properties of the image, particularly the spatial frequency content.

In most urban and agricultural landscapes, remnants of native vegetation are surrounded by an inhospitable matrix. Although vagile species come and go, many reptiles, amphibians and small mammals are effectively stranded and declining towards local extinction. In the same landscapes, other areas where these species are absent are improving in habitat quality, both through natural regeneration and active restoration efforts. So, for many species in many domesticated landscapes, there are too many individuals in some patches of decreasing quality and no individuals in patches of increasing quality. One solution to this situation is to move animals from those areas where there are plenty to suitable areas where there are none. These targeted translocations apply lessons learned from revegetation to dispersal-limited animals to in-fill distributional ranges, increase population size and improve both demographic and genetic connectivity, pushing nonequilibrial metapopulations away from extinction via an imposed mass effect. In contrast to conventional reintroduction schemes—expensive, reactive interventions involving highly-trained specialists and captive-raised endangered species—these inexpensive, proactive, community-driven initiatives aim to avert future declines by keeping common species common. Having introduced the wildlife restoration vision, we use two scenarios to illustrate the benefits of the approach—to species, ecosystem function, ecological understanding, restoration practise and public engagement. As well as adhering to best-practise reintroduction techniques to ensure animal welfare is not compromised and avoid detrimental effects to source populations or release sites, we emphasize community participation, data quality and long-term accessibility as paramount to maximize learning opportunities.

© 2020 Elsevier Ltd To date, there are no interventions that impede the inexorable progression of Alzheimer's disease (AD), and currently-available drugs cholinesterase (AChE) inhibitors and the N-Methyl-D-Aspartate receptor antagonist, memantine, offer only modest symptomatic benefit. Moreover, a range of mechanistically-diverse agents (glutamatergic, histaminergic, monoaminergic, cholinergic) have disappointed in clinical trials, alone and/or in association with AChE inhibitors. This includes serotonin (5-HT) receptor-6 antagonists, despite compelling preclinical observations in rodents and primates suggesting a positive influence on cognition. The emphasis has so far been on high selectivity. However, for a multi-factorial disorder like idiopathic AD, 5-HT6 antagonists possessing additional pharmacological actions might be more effective, by analogy to “multi-target” antipsychotics. Based on this notion, drug discovery programmes have coupled 5-HT6 blockade to 5-HT4 agonism and inhibition of AchE. Further, combined 5-HT6/dopamine D3 receptor (D3) antagonists are of especial interest since D3 blockade mirrors 5-HT6 antagonism in exerting broad-based pro-cognitive properties in animals. Moreover, 5-HT6 and dopamine D3 antagonists promote neurocognition and social cognition via both distinctive and convergent actions expressed mainly in frontal cortex, including suppression of mTOR over-activation and reinforcement of cholinergic and glutamatergic transmission. In addition, 5-HT6 blockade affords potential anti-anxiety, anti-depressive and anti-epileptic properties, and antagonising 5-HT6 receptors may be associated with neuroprotective (“disease-modifying”) properties. Finally D3 antagonism may counter psychotic episodes and D3 receptors themselves offer a promising hub for multi-target agents. The present article reviews the status of “R and D” into multi-target 5-HT6 and D3 ligands for improved treatment of AD and other neurodegenerative disorders of aging. This article is part of the special issue entitled ‘Serotonin Research: Crossing Scales and Boundaries’.

Long duration acoustic monitoring is becoming an increasingly popular approach to extend survey effort by using autonomous sensors to passively collect data over large temporal and spatial scales. This is of particular benefit when attempting to detect a species whose temporal vocalization strategy is unknown, and whose small population size reduces detection probability. It is also of benefit in environments that are logistically difficult to access such as wetlands. We investigated the vocalization strategy of the Least Bittern (Ixobrychus exilis), a species of high conservation concern in the Western hemisphere and ‘in need of management’ in multiple states of the USA. The Least Bittern is a secretive marsh bird that is primarily detected by its vocalizations and call-playback surveys are typically used for population monitoring. To minimize disturbance to both the birds and their habitat, we deployed autonomous acoustic recording units and collected continuous 24-hour audio recordings for 30 days. The resultant accumulation of data necessitated an automated method to assist with analysis and interpretation. We successfully applied a novel soundscape technique—long-duration, false-color (LDFC) spectrograms—to visually confirm presence of Least Bittern from the ‘coo coo coo’ vocalization associated with breeding. In addition, we used a machine learning technique to automate the acoustic event detection process. Peak vocalization times were then predicted from an annotated dataset of actual calls and subsequently used to develop an optimal acoustic survey strategy. The results of this research demonstrate how machine learning methods can search large data sets for a specific species. This information can then be used to optimize existing monitoring methods, to increase detection probability and to minimize associated costs.

Studies of habitat fragmentation have been restricted primarily to anthropogenically-altered habitats, with most research conducted 60–90 years post-fragmentation. It is unclear whether patterns in older systems concur with results from these dynamic landscapes, and hence the long-term viability of populations inhabiting habitat fragments remains largely unexplored. I focused on resident birds in fragments of humid pine-oak forest in Oaxaca, southern Mexico, isolated over 5000 years ago by climate-change. Seventeen fragments, ranging from 2 ha to over 150,000 ha were sampled in 1997 and 1998 yielding 141 species, of which 60 residents were used for analysis. Avian assemblages exhibited a highly nested structure and, with several notable exceptions, assemblages of birds in low-richness fragments were predictable subsets of those in more diverse fragments. Patch-scale factors—area, shape, elevation, habitat diversity and fractal dimension of edge—all exerted strong univariate influence on avian richness but were so closely inter-related that none had a significant independent effect. Thus, larger fragments were more complex in shape, included higher peaks, supported more diverse forests, and contained higher diversities of resident species. In contrast, the landscape-scale index used—distance from nearest large fragment (>50,000 ha)—had little effect on richness. This was reinforced by species-level analyses—one species was significantly influenced by isolation, compared with 31 species that displayed significant minimum-area distributions, restricted to patches larger than a particular threshold value. In terms of autecology, vagility, relative abundance and elevational breadth were closely related to distribution—those species with greater mobility, higher abundances and broader elevational tolerances were consistently more widespread. I suggest that more abundant species were less prone to extinction initially, more vagile species were better dispersers and species with broader elevational tolerances more likely to be successful colonists. As with previous research from older landscapes, patch-scale factors were consistently found to be influential, with high quality fragments supporting diverse communities regardless of landscape context. This suggests that the influence of landscape-scale factors noted in younger, anthropogenically fragmented systems may be transitory, overwhelmed by patch-scale factors with time. Which patch attributes are most influential could not be resolved, however, indicating that even thousands of years after fragmentation, they affect diversity patterns in concert. Rather than differentiating effects of area from habitat heterogeneity and other patch-level factors, I advocate resource-based approaches to understand and manage diversity in habitat fragments.

Oxytocin (OT) has received substantial interest in recent years due to its pro-social and anxiolytic properties. In this study we investigated whether central OT administration facilitates the extinction of social and cued fear in rodents. Social fear was induced by social fear conditioning [1], while cued fear was induced by cued fear conditioning [2]. Social and cued fear extinction were performed 24 h later in a novel environment. OT was administered intracerebroventricularly 10min before the extinction procedure. While central OT completely blocked social fear expression, reversing thereby social fear, it impaired cued fear extinction. Both the facilitatory effect on social fear extinction and the impairing effect on cued fear extinction were mediated by the OT receptors, as administration of an OT receptor antagonist prior to OT blocked the observed effects. At the doses used in the fear extinction studies OT did not alter home cage locomotion, indicating that the observed effects were not a result of impaired locomotion. Taken together, this data suggests that OT has a differential effect on fear extinction in social versus nonsocial contexts, and draws attention to the implications of using OT as a potential adjunct drug in combination with behavioral therapy for psychiatric disorders. Therefore, OT might represent a therapeutically-promising approach in patients with deficits in social functioning, such as social anxiety disorder and autism spectrum disorders. However, in patients where the fear does not involve a social component, such as post-traumatic stress disorder, OT may delay fear extinction.