Understanding constraints to adaptation using a community-centred toolkit.

Worldwide, marginalized and low-income communities will disproportionately suffer climate change impacts while also retaining the least political power to mitigate their consequences. To adapt to environmental shocks, communities must balance intensifying natural resource consumption with the need to ensure the sustainability of ecosystem provisioning services. Thus, scientists have long been providing policy recommendations that seek to balance humanitarian needs with the best outcomes for the conservation of ecosystems and wildlife. However, many conservation and development practitioners from biological backgrounds receive minimal training in either social research methods or participatory project design. Without a clear understanding of the sociocultural factors shaping decision-making, their initiatives may fail to meet their goals, even when communities support proposed initiatives. This paper explores the underlying assumptions of a community's agency, or its ability to develop and enact preferred resilience-enhancing adaptations. We present a context-adaptable toolkit to assess community agency, identify barriers to adaptation, and survey perceptions of behaviour change around natural resource conservation and alternative food acquisition strategies. This tool draws on public health and ecology methods to facilitate conversations between community members, practitioners and scientists. We then provide insights from the toolkit's collaborative development and pilot testing with Vezo fishing communities in southwestern Madagascar. This article is part of the theme issue 'Climate change adaptation needs a science of culture'.

Molecular exploration of fossil eggshell uncovers hidden lineage of giant extinct bird.

The systematics of Madagascar's extinct elephant birds remains controversial due to large gaps in the fossil record and poor biomolecular preservation of skeletal specimens. Here, a molecular analysis of 1000-year-old fossil eggshells provides the first description of elephant bird phylogeography and offers insight into the ecology and evolution of these flightless giants. Mitochondrial genomes from across Madagascar reveal genetic variation that is correlated with eggshell morphology, stable isotope composition, and geographic distribution. The elephant bird crown is dated to ca. 30 Mya, when Madagascar is estimated to have become less arid as it moved northward. High levels of between-clade genetic variation support reclassifying Mullerornis into a separate family. Low levels of within-clade genetic variation suggest there were only two elephant bird genera existing in southern Madagascar during the Holocene. However, we find an eggshell collection from Madagascar's far north that represents a unique lineage of Aepyornis. Furthermore, divergence within Aepyornis coincides with the aridification of Madagascar during the early Pleistocene ca. 1.5 Ma, and is consistent with the fragmentation of populations in the highlands driving diversification and the evolution of extreme gigantism over shorts timescales. We advocate for a revision of their taxonomy that integrates palaeogenomic and palaeoecological perspectives.

Cutmarked bone of drought-tolerant extinct megafauna deposited with traces of fire, human foraging, and introduced animals in SW Madagascar.

People could have hunted Madagascar's megafauna to extinction, particularly when introduced taxa and drought exacerbated the effects of predation. However, such explanations are difficult to test due to the scarcity of individual sites with unambiguous traces of humans, introduced taxa, and endemic megaherbivores. We excavated three coastal ponds in arid SW Madagascar and present a unique combination of traces of human activity (modified pygmy hippo bone, processed estuarine shell and fish bone, and charcoal), along with bones of extinct megafauna (giant tortoises, pygmy hippos, and elephant birds), extirpated fauna (e.g., crocodiles), and introduced vertebrates (e.g., zebu cattle). The disappearance of megafauna from the study sites at ~ 1000 years ago followed a relatively arid interval and closely coincides with increasingly frequent traces of human foraging, fire, and pastoralism. Our analyses fail to document drought-associated extirpation or multiple millennia of megafauna hunting and suggest that a late combination of hunting, forest clearance, and pastoralism drove extirpations.

Madagascar's fire regimes challenge global assumptions about landscape degradation.

Narratives of landscape degradation are often linked to unsustainable fire use by local communities. Madagascar is a case in point: the island is considered globally exceptional, with its remarkable endemic biodiversity viewed as threatened by unsustainable anthropogenic fire. Yet, fire regimes on Madagascar have not been empirically characterised or globally contextualised. Here, we contribute a comparative approach to determining relationships between regional fire regimes and global patterns and trends, applied to Madagascar using MODIS remote sensing data (2003-2019). Rather than a global exception, we show that Madagascar's fire regimes are similar to 88% of tropical burned area with shared climate and vegetation characteristics, and can be considered a microcosm of most tropical fire regimes. From 2003-2019, landscape-scale fire declined across tropical grassy biomes (17%-44% excluding Madagascar), and on Madagascar at a relatively fast rate (36%-46%). Thus, high tree loss anomalies on the island (1.25-4.77× the tropical average) were not explained by any general expansion of landscape-scale fire in grassy biomes. Rather, tree loss anomalies centred in forests, and could not be explained by landscape-scale fire escaping from savannas into forests. Unexpectedly, the highest tree loss anomalies on Madagascar (4.77×) occurred in environments without landscape-scale fire, where the role of small-scale fires (<21 h [0.21 km2 ]) is unknown. While landscape-scale fire declined across tropical grassy biomes, trends in tropical forests reflected important differences among regions, indicating a need to better understand regional variation in the anthropogenic drivers of forest loss and fire risk. Our new understanding of Madagascar's fire regimes offers two lessons with global implications: first, landscape-scale fire is declining across tropical grassy biomes and does not explain high tree loss anomalies on Madagascar. Second, landscape-scale fire is not uniformly associated with tropical forest loss, indicating a need for socio-ecological context in framing new narratives of fire and ecosystem degradation.

Late Pleistocene/Early Holocene sites in the montane forests of New Guinea yield early record of cassowary hunting and egg harvesting.

How early human foragers impacted insular forests is a topic with implications across multiple disciplines, including resource management. Paradoxically, terminal Pleistocene and Early Holocene impacts of foraging communities have been characterized as both extreme-as in debates over human-driven faunal extinctions-and minimal compared to later landscape transformations by farmers and herders. We investigated how rainforest hunter-gatherers managed resources in montane New Guinea and present some of the earliest documentation of Late Pleistocene through mid-Holocene exploitation of cassowaries (Aves: Casuariidae). Worldwide, most insular ratites were extirpated by the Late Holocene, following human arrivals, including elephant birds of Madagascar (Aepyornithidae) and moa of Aotearoa/New Zealand (Dinornithiformes)-icons of anthropogenic island devastation. Cassowaries are exceptional, however, with populations persisting in New Guinea and Australia. Little is known of past human exploitation and what factors contributed to their survival. We present a method for inferring past human interaction with mega-avifauna via analysis of microstructural features of archaeological eggshell. We then contextualize cassowary hunting and egg harvesting by montane foragers and discuss the implications of human exploitation. Our data suggest cassowary egg harvesting may have been more common than the harvesting of adults. Furthermore, our analysis of cassowary eggshell microstructural variation reveals a distinct pattern of harvesting eggs in late ontogenetic stages. Harvesting eggs in later stages of embryonic growth may reflect human dietary preferences and foraging seasonality, but the observed pattern also supports the possibility that-as early as the Late Pleistocene-people were collecting eggs in order to hatch and rear cassowary chicks.

Late Holocene spread of pastoralism coincides with endemic megafaunal extinction on Madagascar.

Recently expanded estimates for when humans arrived on Madagascar (up to approximately 10 000 years ago) highlight questions about the causes of the island's relatively late megafaunal extinctions (approximately 2000-500 years ago). Introduced domesticated animals could have contributed to extinctions, but the arrival times and past diets of exotic animals are poorly known. To conduct the first explicit test of the potential for competition between introduced livestock and extinct endemic megafauna in southern and western Madagascar, we generated new radiocarbon and stable carbon and nitrogen isotope data from the bone collagen of introduced ungulates (zebu cattle, ovicaprids and bushpigs, n = 66) and endemic megafauna (pygmy hippopotamuses, giant tortoises and elephant birds, n = 68), and combined these data with existing data from endemic megafauna (n = 282, including giant lemurs). Radiocarbon dates confirm that introduced and endemic herbivores briefly overlapped chronologically in this region between 1000 and 800 calibrated years before present (cal BP). Moreover, stable isotope data suggest that goats, tortoises and hippos had broadly similar diets or exploited similar habitats. These data support the potential for both direct and indirect forms of competition between introduced and endemic herbivores. We argue that competition with introduced herbivores, mediated by opportunistic hunting by humans and exacerbated by environmental change, contributed to the late extinction of endemic megafauna on Madagascar.

How can evolutionary and biological anthropologists engage broader audiences?

OBJECTIVES: With our diverse training, theoretical and empirical toolkits, and rich data, evolutionary and biological anthropologists (EBAs) have much to contribute to research and policy decisions about climate change and other pressing social issues. However, we remain largely absent from these critical, ongoing efforts. Here, we draw on the literature and our own experiences to make recommendations for how EBAs can engage broader audiences, including the communities with whom we collaborate, a more diverse population of students, researchers in other disciplines and the development sector, policymakers, and the general public. These recommendations include: (1) playing to our strength in longitudinal, place-based research, (2) collaborating more broadly, (3) engaging in greater public communication of science, (4) aligning our work with open-science practices to the extent possible, and (5) increasing diversity of our field and teams through intentional action, outreach, training, and mentorship. CONCLUSIONS: We EBAs need to put ourselves out there: research and engagement are complementary, not opposed to each other. With the resources and workable examples we provide here, we hope to spur more EBAs to action.

Social memory and niche construction in a hypervariable environment.

BACKGROUND: Communities in southwest Madagascar have co-evolved with a hypervariable environment and climate. The paleoclimate record reflects major fluctuations in climatic conditions over the course of Holocene human settlement. Archeological evidence indicates short-term occupations of sites, suggesting that frequent residential mobility and flexible subsistence strategies have been central features of life on the southwest coast for millennia. Today, despite rapid changes linked to globalization and increasing market integration, mobility and subsistence flexibility remain key to the lives of communities of the region. AIMS: In this article, we advocate closer consideration of the social dimensions of the human niche, and their inextricable links to the biophysical world. Specifically, we explore the theoretical implications of applying a Niche Construction Theory framework to understanding the role of social memory in constructing the human niche of SW Madagascar. We look at how social memory facilitates mobility, resource use, and the creation and maintenance of social identities and ties among communities of foragers, farmers, herders, and fishers living under hypervariable climatic conditions. MATERIALS & METHODS: We conducted an extensive oral history survey in SW Madagascar between 2017 and 2018. We interviewed over 100 elders from 32 different communities. RESULTS: Our analysis of the oral history archive resulted in the development of a theoretical model of human niche construction centered on the maintenance and transmission of social memory. DISCUSSION: We argue that social memory and the ability to transmit oral histories of exchange, reciprocity, and cooperation, as well as ecological knowledge are key adaptive mechanisms that facilitate mobility and access to resources in a hypervariable environment. CONCLUSION: The preservation and transmission of oral histories and ecological knowledge are thus critical to future resilience and sustainability.

Amy ty lilin-draza'ay: Building Archaeological Practice on Principles of Community.

The significant economic and health impacts of the COVID-19 pandemic have forced archaeologists to consider the concept of resilience in the present day, as it relates to their profession, students, research projects, cultural heritage, and the livelihoods and well-being of the communities with a stake in the sites they study. The global crisis presents an opportunity to cement archaeological practice in a foundation of community building. We can learn from the ancestors, razana, how investing in community-social networks at different scales-makes us more resilient to crises. In so doing, we can improve the quality and equity of the science we produce and ensure relevant outcomes for living communities and future generations.

Les impacts économiques et de santé considérables de la pandémie COVID-19 obligent les archéologues à considérer le concept de résilience à l'heure actuelle, en ce qui concerne leur profession, leurs étudiants, leurs projets de recherche, le patrimoine culturel et les modes de vie et le bien-être des communautés ayant un intérêt dans les sites qu'ils étudient. La crise mondiale offre une opportunité de cimenter la pratique archéologique dans un fondement communautaire. Nous pouvons apprendre de nos ancêtres, les razana, que le fait d'investir dans des réseaux communautaires et sociaux à différentes échelles nous rend plus résistants aux crises. Ce faisant, nous pouvons améliorer la qualité et l'équité de la science que nous produisons et garantir des résultats pertinents pour les communautés vivantes et les générations futures.

Archaeology, environmental justice, and climate change on islands of the Caribbean and southwestern Indian Ocean.

Climate change impacts island communities all over the world. Sea-level rise, an increase in the frequency and intensity of severe weather events, and changes in distribution and health of marine organisms are among the most significant processes affecting island communities worldwide. On islands of the Caribbean and southwestern Indian Ocean (SWIO), however, today's climate change impacts are magnified by historical environmental injustice and colonial legacies, which have heightened the vulnerability of human and other biotic communities. For some islands, archaeological and paleoecological research offers an important record of precolonial climate change and its interplay with human lives and landscapes. The archaeological record suggests strategies and mechanisms that can inform discussions of resilience in the face of climate change. We detail climate-related challenges facing island Caribbean and SWIO communities using archaeological and paleoecological evidence for past climate change and human response and argue that these cannot be successfully addressed without an understanding of the processes that have, over time, disrupted livelihoods, reshaped land- and seascapes, threatened intergenerational ecological knowledge transfer, and led to increased inequality and climate vulnerability.

Micro Methods for Megafauna: Novel Approaches to Late Quaternary Extinctions and Their Contributions to Faunal Conservation in the Anthropocene.

Drivers of Late Quaternary megafaunal extinctions are relevant to modern conservation policy in a world of growing human population density, climate change, and faunal decline. Traditional debates tend toward global solutions, blaming either dramatic climate change or dispersals of Homo sapiens to new regions. Inherent limitations to archaeological and paleontological data sets often require reliance on scant, poorly resolved lines of evidence. However, recent developments in scientific technologies allow for more local, context-specific approaches. In the present article, we highlight how developments in five such methodologies (radiocarbon approaches, stable isotope analysis, ancient DNA, ancient proteomics, microscopy) have helped drive detailed analysis of specific megafaunal species, their particular ecological settings, and responses to new competitors or predators, climate change, and other external phenomena. The detailed case studies of faunal community composition, extinction chronologies, and demographic trends enabled by these methods examine megafaunal extinctions at scales appropriate for practical understanding of threats against particular species in their habitats today.

Archaeological assessment reveals Earth's early transformation through land use.

Environmentally transformative human use of land accelerated with the emergence of agriculture, but the extent, trajectory, and implications of these early changes are not well understood. An empirical global assessment of land use from 10,000 years before the present (yr B.P.) to 1850 CE reveals a planet largely transformed by hunter-gatherers, farmers, and pastoralists by 3000 years ago, considerably earlier than the dates in the land-use reconstructions commonly used by Earth scientists. Synthesis of knowledge contributed by more than 250 archaeologists highlighted gaps in archaeological expertise and data quality, which peaked for 2000 yr B.P. and in traditionally studied and wealthier regions. Archaeological reconstruction of global land-use history illuminates the deep roots of Earth's transformation and challenges the emerging Anthropocene paradigm that large-scale anthropogenic global environmental change is mostly a recent phenomenon.

Historical perspectives on contemporary human-environment dynamics in southeast Africa.

The human communities and ecosystems of island and coastal southeast Africa face significant and linked ecological threats. Socioecological conditions of concern to communities, governments, nongovernmental organizations, and researchers include declining agricultural productivity, deforestation, introductions of non-native flora and fauna, coastal erosion and sedimentation, damage to marine environments, illegal fishing, overfishing, waste pollution, salinization of freshwater supplies, and rising energy demands, among others. Human-environment challenges are connected to longer, often ignored, histories of social and ecological dynamics in the region. We argue that these challenges are more effectively understood and addressed within a longer-term historical ecology framework. We reviewed cases from Madagascar, coastal Kenya, and the Zanzibar Archipelago of fisheries, deforestation, and management of human waste to encourage increased engagement among historical ecologists, conservation scientists, and policy makers. These case studies demonstrate that by widening the types and time depths of data sets we used to investigate and address current socioecological challenges, our interpretations of their causes and strategies for their mitigation varied significantly.

Perspectivas Históricas sobre las Dinámicas Contemporáneas entre Humanos y el Ambiente en el Sureste de África Resumen Las comunidades humanas y los ecosistemas de las costas del sureste africano enfrentan amenazas ecológicas significativas y vinculadas. Las condiciones socio-ecológicas que preocupan a las comunidades, los gobiernos, las organizaciones no gubernamentales y a los investigadores incluyen la poductividad agrícola en declinación, la deforestación, la introducción de flora y fauna no nativa, la sedimentación y erosión costera, el daño hacia los ecosistemas marinos, la pesca ilegal, la sobrepesca, la contaminación por desechos, la salinización de las cuencas de agua dulce, y la creciente demanda de energía, entre otras. Los retos humanos - ecosistema están conectados con historias más largas, y frecuentemente ignoradas, de dinámicas sociales y ecológicas en la región. Argumentamos que estos retos se entienden y se tratan con mayor efectividad dentro de un marco de trabajo de ecología histórica con un periodo más largo. Revisamos casos de pesquerías, deforestación y manejo de desechos humanos en Madagascar, la costa de Kenia y el archipiélago de Zanzíbar para propiciar una mayor participación entre los ecologistas históricos, los científicos de la conservación, y los legisladores. Estos estudios de caso demuestran que al ampliar los tipos y la temporalidad de los conjuntos de datos que usamos para investigar y tratar los retos socio-ecológicos contemporáneos, nuestras interpretaciones de las causas de estos retos y las estrategias para su mitigación variaron significativamente.