Using paleo-archives to safeguard biodiversity under climate change

Using the past to inform the future The late Quaternary paleorecord, within the past ∼130,000 years, can help to inform present-day management of the Earth's ecosystems and biota under climate change. Fordham et al. review when and where rapid climate transitions can be found in the paleoclimate record. They show how such events in Earth's history can shape our understanding of the consequences of future global warming, including rates of biodiversity loss, changes in ecosystem structure and function, and degradation in the goods and services that these ecosystems provide to humanity. They also highlight how recent developments at the intersection of paleoecology, paleoclimatology, and macroecology can provide opportunities to anticipate and manage the responses of species and ecosystems to changing climates in the Anthropocene. Science, this issue p. eabc5654 BACKGROUND Effects of recent global warming have been documented in every biome on Earth. Safeguarding biodiversity and ecosystem services against future impacts requires reliable predictions of climate-driven biological responses and effective solutions. Integrated research in paleoecology, paleogenomics, paleoclimatology, and macroecology offers new prospects for projecting and managing current biotic responses to climate change. By revealing mechanisms that shaped past and present biodiversity patterns, this interdisciplinary intersection provides an empirical foundation for anticipating responses to accelerated climate change. New insights are coming from developments in high-throughput sequencing, computational technologies, ecological simulation models, and increased spatiotemporal resolution of paleoenvironmental data from late Quaternary paleo-records (the past ~130,000 years). Although these advances reveal biodiversity responses to past global change, benefits for improving forecasting of biodiversity impacts and refining conservation policies are lagging. Abundant opportunities exist for using the late Quaternary paleo-record to inform conservation practices and policies in the context of climate change. ADVANCES The threat of anthropogenic climate change demands that conservationists seek more effective ways of improving management of biodiversity and ecosystems. Analytical approaches that combine high-resolution paleoclimate proxy and simulation data, precisely dated fossils, and genetic diversity estimates from ancient DNA are unveiling biotic responses to various rates and magnitudes of natural climate warming, some comparable with 21st century projections. Reference periods in Earth’s history provide natural laboratories for testing fundamental ecological theory and offer opportunities to identify ecological processes that influence the likelihood of extinction and ecosystem change, to test efficacy of threatened-species assessments and resilience of biota during periods of abrupt warming, and to locate biogeographic areas that remain stable under shifting climates. Refinement of essential biodiversity variables by using past biodiversity dynamics will improve our understanding of climate-driven shifts in species populations, community composition, and ecosystem structure and function. From this, biodiversity early-warning systems, conservation strategies, and decision-making tools can be tested at fine-grain spatiotemporal scales, providing an evidence base for understanding and improving projections of species- and ecosystem-level collapse. OUTLOOK As paleo-archives become more routinely integrated into conservation science, guidelines for the management of nature will benefit from understanding how different spatiotemporal scales of past climate change affected species and ecosystems across the planet. This will require global initiatives to harmonize vast numbers of paleoclimate-proxy and paleoecological records with high-resolution paleoclimate projections from Earth system models. Paleoecological data offer a means to disentangle climate and nonclimate drivers of biodiversity and ecosystem function, particularly in concert with simulation models and integrated analytical techniques that compare biotic change across regions with contrasting histories of human colonization and land use. Moreover, developments in paleogenomics that pinpoint adaptation across and within species will identify microevolutionary processes that lend resilience to biodiversity in shifting climates. Incorporating paleo-archives in conservation policies will equip decision-makers with improved strategies for mitigating biodiversity loss from climate change in the Anthropocene. Paleo-archives offer new prospects for benchmarking and maintaining future biodiversity. Integrated research using paleo-archives provides empirical foundations for contextualizing climate-driven changes in species populations, community composition, and ecosystem structure and function. These observations can inform conservation strategies under anthropogenic climate change. CREDITS: HUNG CHUNG CHIH, WANG LIQIANG, ANDREI STEPANOV, AUSTRALIANCAMERA, ALHOVIK, BLUERING MEDIA, NAZARII M, ANDERS SVENSSON/ SHUTTERSTOCK Strategies for 21st-century environmental management and conservation under global change require a strong understanding of the biological mechanisms that mediate responses to climate- and human-driven change to successfully mitigate range contractions, extinctions, and the degradation of ecosystem services. Biodiversity responses to past rapid warming events can be followed in situ and over extended periods, using cross-disciplinary approaches that provide cost-effective and scalable information for species’ conservation and the maintenance of resilient ecosystems in many bioregions. Beyond the intrinsic knowledge gain such integrative research will increasingly provide the context, tools, and relevant case studies to assist in mitigating climate-driven biodiversity losses in the 21st century and beyond.