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Phytolith assemblages reflect variability in human land use and the modern environmentNARA Subscribed
Phytoliths preserved in soils and sediments can be used to provide unique insights into past vegetation dynamics in response to human and climate change. Phytoliths can reconstruct local vegetation in terrestrial soils where pollen grains typically decay, providing a range of markers (or lack thereof) that document past human activities. The ca. 6 million km 2 of Amazonian forests have relatively few baseline datasets document...
Warming, drought, and disturbances lead to shifts in functional composition: A millennial‐scale analysis for Amazonian and Andean sitesNARA Subscribed
Tropical forests are changing in composition and productivity, probably in response to changes in climate and disturbances. The responses to these multiple environmental drivers, and the mechanisms underlying the changes, remain largely unknown. Here, we use a functional trait approach on timescales of 10,000 years to assess how climate and disturbances influence the community‐mean adult height, leaf area, seed mass, and wood...
Aim To determine the timing of megafaunal extinction in the high plains of Peru and also to determine if the timing was delayed in grasslands compared with previously published forested settings to dissociate the effects of succession from human or climatic impacts. Location The Junín Plateau, Peru. Taxon Flowering plants and Ascomycetes. Methods The sediments used in this analysis were collected from the edge of Lake Junín, P...
Comprehensive analysis of epigenetic clocks reveals associations between disproportionate biological ageing and hippocampal volumeNARA Subscribed
The concept of age acceleration, the difference between biological age and chronological age, is of growing interest, particularly with respect to age-related disorders, such as Alzheimer’s Disease (AD). Whilst studies have reported associations with AD risk and related phenotypes, there remains a lack of consensus on these associations. Here we aimed to comprehensively investigate the relationship between five recognised meas...
Prolonging survival in good health is a fundamental societal goal. However, the leading determinants of disability-free survival in healthy older people have not been well established. Data from ASPREE, a bi-national placebo-controlled trial of aspirin with 4.7 years median follow-up, was analysed. At enrolment, participants were healthy and without prior cardiovascular events, dementia or persistent physical disability. Disab...
Little is known about whether changes in lake ecosystem structure over the past 150 years are unprecedented when considering longer timescales. Similarly, research linking environmental stressors to lake ecological resilience has traditionally focused on a few sentinel sites, hindering the study of spatially synchronous changes across large areas. Here, we studied signatures of paleolimnological resilience by tracking change i...
Modern pollen assemblages of the NeotropicsNARA Subscribed
Aim Modern pollen assemblages provide a means to calibrate fossil pollen data and to provide a translation from habitat and vegetation type to pollen representation. Here we provide a database of modern pollen abundances from a broad range of neotropical habitats and locations. Location The Neotropics, especially western Amazonia, the Andes, The Galápagos, Central America, Puerto Rico and Mexico. Taxon Angiosperms and Gymnospe...
Aim To investigate cerrado responses to glacial–interglacial climate change and the potential for connective rain forest corridors between the Atlantic Coastal Forest and Amazonian rain forest. Location The crater lake of Serra Negra (18 °S, 46 °W) in Minas Gerais, Brazil. Taxon 117 fossil pollen types, 22 non‐pollen palynomorphs were documented. Methods We recovered 7.82 m of sediment from the lake, and analysed fossil pollen...
Vegetation response to climatic changes in western Amazonia over the last 7,600 yearsNARA Subscribed
Aim Ongoing and future anthropogenic climate change poses one of the greatest threats to biodiversity, affecting species distributions and ecological interactions. In the Amazon, climatic changes are expected to induce warming, disrupt precipitation patterns and of particular concern, to increase the intensity and frequency of droughts. Yet the response of ecosystems to intense warm, dry events is not well understood. In the A...
A 7000‐year history of changing plant trait composition in an Amazonian landscape; the role of humans and climateNARA Subscribed
Tropical forests are shifting in species and trait composition, but the main underlying causes remain unclear because of the short temporal scales of most studies. Here, we develop a novel approach by linking functional trait data with 7000 years of forest dynamics from a fossil pollen record of Lake Sauce in the Peruvian Amazon. We evaluate how climate and human disturbances affect community trait composition. We found weak r...