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The response of aquatic ecosystems in the Sierra Nevada (California, USA) to late Quaternary hydroclimate changes remains mostly unknown. Mono Lake, a large endorheic lake just east of the Sierra Nevada, contains an expanded archive of laminated sediments that can be used to examine the response of benthos to environmental changes. Fossil ostracodes from a radiocarbon‐dated core were used to examine paleoecologic changes from ~16.6 to 4.3k cal a bp. Seven species were identified, with the co‐occurrence of Limnocythere ceriotuberosa and Limnocythere staplini indicating a large SO42−‐rich lake in the Pleistocene. The Younger Dryas was complex, with Fabaeformiscandona caudata reflecting a cold and deep lake ~13.0–12.2k cal a bp, followed by an interval of extensive littoral habitat from ~12.2–11.6k cal a bp. Ostracode diversity, valves g–1 and the ratio of adult:juvenile valves declined after ~10.7k cal a bp due to regression, altered hydrochemistry and seasonal anoxia. Strong seasonality during the Early Holocene is suggested by the presence of reworked ostracodes and macrocharcoal, delivered to Mono Lake by erosion of ancient lake beds in the basin. A depauperate ostracode fauna in the Middle Holocene suggests a strong sensitivity to drought in this ecosystem, which has implications for biodiversity in the future. [ABSTRACT FROM AUTHOR]

Aim: Owing to its diverse bioclimatic zones, long human history and intense anthropogenic impacts, Africa provides a model system for studying how global terrestrial ecosystems might respond to accelerated socio‐environmental stress. Africa is particularly vulnerable to climate change and human impact, and insufficient baseline data hamper current environmental management efforts. Using palaeoecological data, we seek to identify the timing, pace and drivers of change in African biomes on a long‐term scale to inform current ecosystem management frameworks on the continent. Location: Africa. Time period: 0–12 ka. Major taxa studied: African biomes. Methods: Sixty‐four pollen records across Africa and nearby sites were retrieved from multiple databases/sources and grouped into biomes. Turnover (quantified using the squared chord distance dissimilarity metric) and rarefaction analyses were conducted on pollen records in each biome group to reconstruct regional temporal vegetation turnover and richness. Reconstructed vegetation turnover and richness were compared with independent records of climate, fire and human activity to identify possible drivers of change. Results: We found that the most stable biomes were those with the greatest floristic richness. Southern Africa's mediterranean‐type (SAM) ecosystems were the most stable and northern Africa's mediterranean‐type (NAM) ecosystems were the most unstable (mainly owing to fire). Tropical savannas (TS) and SAM ecosystems expressed the most sensitivity to climatic shifts from ≥6 ka, whereas tropical forests (TF) were relatively stable before human activities intensified from c. 2 ka. Floristic richness also declined across the tropics from c. 2 ka. Main conclusions: Our analysis pinpoints NAM ecosystems as undergoing the fastest acceleration in turnover on the continent in response to fire, whereas TF and TS have been undergoing unprecedented changes in biodiversity in the last 2,000 years. We expect further changes in biodiversity where climate becomes warmer and drier and where human impacts are novel and rapid in comparison to long‐term baselines. [ABSTRACT FROM AUTHOR]

The Southeast Asian rainforest region is extremely complex and biodiverse. Fossils have shown that paleo‐Antarctic rainforest lineages (PARLs) now extant in Asia tracked the ever‐wet conditions needed to survive and diversify through deep time. However, the threat of future climate change to the remaining rainforest and PARLs in Southeast Asia has yet to be evaluated to set conservation priorities. We first quantified the woody‐genus floristic relationships of Southeast Asian Island Groups by vetting and analyzing recent compilations of bioregional species data. We then evaluated the contributions to community assembly of woody fossil lineages and Island Group relationships to environmental gradients. To better understand climatic constraints of fossil lineage distributions and forecast distributions under projected future climate, we used exemplar living woody PARLs, including two angiosperms and two gymnosperms. Generalized linear models were used to project potential distributions under future climate pathways that assume no reduction in carbon dioxide emissions. The floristic analyses highlighted strong similarities among Island Groups in the ever‐wet forest areas of Malesia, where PARLs are often concentrated. Ordination outliers represented more seasonal locations. Species distribution models showed that potential future distributions of ancient lineages are constrained by increasing rainfall seasonality and higher seasonal temperatures, with significant differences among exemplar genera. Notably, potential distributions often mapped onto de facto inaccessible areas, where forest clearing and the ubiquitous marine dispersal barriers that characterize the region will drastically inhibit potential relocation. These realities gravely threaten paleo‐conservation values and contemporary rainforest community assembly processes in Southeast Asia. [ABSTRACT FROM AUTHOR]

Aim: Dryland ecosystems, such as those in southern Arabia, are particularly vulnerable to climate and land‐use change. Aridification and human subsistence changes at the end of the Holocene Humid Period at 6–4 ka have been used as an iconic example for evaluating such impacts to resilience of arid systems. Although records of ancient environments can provide critical insight into the biotic and abiotic mechanisms that alter ecosystems, traditional archives, such as lake deposits, are not common in southern Arabia after 6 ka; thus, we must use alternative archives. Location: Yemen. Taxon: Plants; Rock Hyrax (Procavia capensis). Methods: We use fossil pollen and stable isotopes (δ15N; δ13C) of rock hyrax (P. capensis) middens from Wadi Sana, Yemen, to look at changes in ecosystem structure and function across this key transition from 6 ka to the present. A total of 17 middens were radiocarbon‐dated and stable isotopes were measured. Of these, pollen was extracted from hyraceum of 14 middens and identified using a light microscope. Fossil pollen assemblages were then compared to existing modern pollen samples from throughout Arabia. Results: During the mid‐Holocene from at least 6 to 4.7 ka, the pollen flora reflects a landscape with abundant tropical trees. These included foundational woody taxa, such as Terminalia and Boswellia sacra (frankincense), which had a strong positive influence on local hydrology and the economy, respectively. Increased charcoal abundances also suggest that wildfire occurred periodically. Main conclusions: Connections with archaeological evidence suggest a strong link between human management and the presence of Terminalia woodland during the mid‐Holocene. These may have promoted increased groundwater storage and ponding as regional rainfall was decreasing. The mid‐Holocene expansion of Boswellia sacra (frankincense) may have helped support resin trade that became a critical export from the region. Fires were more common than today, suggesting semi‐arid but continuous vegetation cover across what is now bare ground. Finally, after 1 ka, increased sedge abundances at the expense of grasses and trees suggest the development of desert conditions. [ABSTRACT FROM AUTHOR]

Hunter‐gatherers, especially Pleistocene examples, are not well‐represented in archeological studies of niche construction. However, as the role of humans in shaping environments over long time scales becomes increasingly apparent, it is critical to develop archeological proxies and testable hypotheses about early hunter‐gatherer impacts. Modern foragers engage in niche constructive behaviors aimed at maintaining or increasing the productivity of their environments, and these may have had significant ecological consequences over later human evolution. In some cases, they may also represent behaviors unique to modern Homo sapiens. Archeological and paleoenvironmental data show that African hunter‐gatherers were niche constructors in diverse environments, which have legacies in how ecosystems function today. These can be conceptualized as behaviorally mediated trophic cascades, and tested using archeological and paleoenvironmental proxies. Thus, large‐scale niche construction behavior is possible to identify at deeper time scales, and may be key to understanding the emergence of modern humans. [ABSTRACT FROM AUTHOR]

This paper explores what sustainability managers do when attempting to scale sustainability to a strategic level within their organization. Drawing on semistructured interview data with 44 sustainability managers in large, for‐profit companies, we identify three distinct scaling microstrategies that individuals use when scaling sustainability. We label these conforming, leveraging, and shaping. Our analysis also finds that sustainability managers deploy combinations of these microstrategies in three distinct approaches, which we call the assimilation approach, the mobilization approach, and the transition approach. Finally, we interrogate the degree to which employing these different approaches achieves a peripheral, intermediate, or strategic scale of sustainability within the organizations represented in the study. Our paper contributes to theory and practice at the interface of strategy and sustainability by developing a practice‐based Scaling Approach Framework, whereby an assimilation approach is associated with organizations with sustainability at a peripheral scale, a mobilization approach is associated with an intermediate scale of sustainability, and a transition approach is associated with scaling sustainability to a strategic level. From these results, we propose a Scaling Progression Model that reflects the phases that individuals progress through when scaling sustainability. [ABSTRACT FROM AUTHOR]

Aim: The climate tolerances of many species are broader than those estimated from current native ranges. Indeed, the niches of some Afromontane trees are up to 50% larger after incorporation of fossil data. This expansion could reduce estimates of species' future range loss owing to climate change but also implies strong non‐climatic limitations on species' current ranges. One such limitation is land use, which fossil data suggest influences Afromontane tree distribution, preventing these trees from occupying warmer conditions than they do currently. We aimed to assess the degree to which the broader climatic tolerances revealed by fossil data buffer projected range loss from climate and land use for Afromontane trees. Location: Africa. Time period: Last 21,000 years. Major taxa studied: Afromontane trees. Methods: We used species distribution models informed by both current and fossil distributions to project future ranges under climate and land‐use projections. Results: We found that projected range reductions are only slightly ameliorated by incorporation of fossil distributions, and these improvements diminish further under severe land‐use or climate change scenarios. Taxa that are less impacted by climate are more impacted by intense land use. Depending on the severity of climate and land use, the geographical extent of Afromontane tree species' ranges will contract by 40–85%, and the trees will be completely lost from large portions of Africa. We projected that the surviving species' ranges will become increasingly fragmented. Main conclusions: Maintaining Afromontane ecosystems will require mitigation of both climate and land‐use change and protection of areas to optimize connectivity. Our findings caution that species with climate tolerances broader than their current range might not necessarily fare better under strong changes in climate or land use. [ABSTRACT FROM AUTHOR]

Abstract: African ecosystems are at great risk. Despite their ecological and economic importance, long‐standing ideas about African forest ecology and biogeography, such as the timing of changes in forest extent and the importance of disturbance, have been unable to be tested due to a lack of sufficiently long records. Here, we present the longest continuous terrestrial record of late Quaternary vegetation from southern Africa collected to date from a drill core from Lake Malawi covering the last ~600,000 years. Pollen analysis permits us to investigate changes in vegetation structure and composition over multiple climatic transitions. We observe nine phases of forest expansion and collapse related to regional hydroclimate change. The development of desert, steppe and grassland vegetation during arid periods is likely dynamically linked to thresholds in regional hydrology associated with lake level and moisture recycling. Species composition of these dryland ecosystems varied greatly and is unlike the vegetation found at Malawi today, with assemblages suggesting strong Somali‐Masai affinities. Furthermore, nearly all semiarid assemblages contain low forest taxa abundances, suggesting that moist lowland gallery forests formed refugia along waterways during arid times. When the region was wet, forests were species‐rich and very high afromontane tree abundances suggest frequent widespread lowland colonization by modern high elevation trees. Furthermore, species composition varied little amongst forest phases until ~80 ka when disturbance tolerant tree taxa characteristic of the modern vegetation increased in abundance. The waxing and waning of forests has important implications for understanding the processes that control modern tropical vegetation biogeography as well as the environments of early humans across Africa. Finally, this work highlights the resilience of montane forests during previous warm intervals, which is relevant for future climate change; however, we point to a fundamental shift in disturbance regimes which are crucial for the structure and composition of modern East African landscapes. [ABSTRACT FROM AUTHOR]

Biodiversity indicators are widely used tools to help determine rates of biodiversity change and the success or failure of efforts to conserve it. However, their sufficiency and suitability in providing information for decision-makers is unclear. Here, we review the indicators brought together under the Biodiversity Indicator Partnership to monitor progress towards the Aichi Targets to determine where there are gaps. Of the 20 Aichi Biodiversity Targets, Targets 2, 3, and 15 are missing indicators entirely. Scoring the indicators in relation to their alignment, temporal relevance and spatial scale shows additional gaps under Targets 1, 13, and 16-20. Predominately, gaps were found to be socio-economic in nature (i.e., benefits, pressures, and responses) rather than status-related (i.e., states), principally due to a poor alignment between the indicator and the text of the Aichi Target. Hence, it is critical that existing indicators are properly resourced and maintained and new indicators developed to be able to effectively monitor biodiversity and its influencing factors to 2020 and beyond. [ABSTRACT FROM AUTHOR]

Aim Climate and land-use change will have a dramatic impact on future ecosystems through alterations to species ranges and community composition. When forming conservation strategies, correlative species distribution models are often created to assess risks for individual species. These models are based on the assumption of climatic equilibrium, such that the modern range is representative of the full range of conditions under which species could thrive. However, the palaeo-ecological record illustrates examples of disequilibrium in species today, and recent studies suggest that many species could occur in much broader climatic settings than previously thought. Montane ecosystems are thought to be at disproportionate risk due to temperature sensitivity and restricted geographical ranges. However, in the Afrotropics the palaeo-ecological record shows that montane forest taxa expanded into the lowlands numerous times, suggesting a possible tolerance to warm temperatures. Location Africa. Methods We integrate palaeo-ecological and palaeo-climatic data in order to compare climate conditions in which species are currently found with those in the past. We use species distribution models to construct potential modern ranges for Afromontane species based on modern distributions and distributions in the palaeo-ecological record in order to evaluate the equilibrium of species ranges. Results We show that many Afromontane trees have occupied warmer climates in the past, which suggests that the current low-elevation boundaries are not set by climate. Interestingly, the species with the largest disequilibrium between palaeo- and modern distributions are those whose modern distributions show the least temperature sensitivity. Mapping of species potential ranges based on modern and palaeo- distributions clearly shows that suitable climate conditions exist today in the lowlands for less temperature-sensitive species. Main conclusions These results imply that the current range of these forest trees does not necessarily inform risk from climatic change, and that human land use may be the major pressure for many species in the future. [ABSTRACT FROM AUTHOR]

Conservation policy decisions can suffer from a lack of evidence, hindering effective decision‐making. In nature conservation, studies investigating why policy is often not evidence‐informed have tended to focus on Western democracies, with relatively small samples. To understand global variation and challenges better, we established a global survey aimed at identifying top barriers and solutions to the use of conservation science in policy. This obtained the views of 758 people in policy, practice, and research positions from 68 countries across six languages. Here we show that, contrary to popular belief, there is agreement between groups about how to incorporate conservation science into policy, and there is thus room for optimism. Barriers related to the low priority of conservation were considered to be important, while mainstreaming conservation was proposed as a key solution. Therefore, priorities should focus on convincing the public of the importance of conservation as an issue, which will then influence policy‐makers to adopt pro‐environmental long‐term policies. [ABSTRACT FROM AUTHOR]