Biology subjects

Nogues-Bravo, D.

Publications and source records attributed to Nogues-Bravo, D..

3 recordsLinked to original sources

bioRxiv2021

Combining taxonomic, phylogenetic and functional diversity reveals new global priority areas for tetrapod conservation

Human activities have eroded biodiversity, yet the varying influence of past versus recent impacts across the distinct facets of biodiversity is still poorly understood. Weighting taxonomic information by phylogenetic and functional diversity in a novel multifaceted index (-Diversity) across more than 17,000 tetrapod species, we show the geography of multifaceted tetrapod diversity, and the role of climate stability and water-energy dynamics coupled with the timing of inception of agriculture in explaining broad-scale patterns of tetrapod diversity. In particular, the varying geography of the timing of agriculture expansion since the Neolithic affected -Diversity at least as much as recent human impacts, especially in birds, mammals, and reptiles, suggesting that human imprints may have shaped tetrapod diversity for millennia through legacy effects of past land use modifications. The long-lasting effect of humans will only accelerate, as the most diverse areas for -Diversity (tropical Africa, South East Asia and Central and South America) are disproportionally exposed to both future climate and land-use change.

ecology↗

bioRxiv2021

Climate and genetic diversity change in mammals during the Late Quaternary

Conservation decisions and future scenarios are in need of past baselines on climate change impacts in biodiversity. Although we know that climate change has contributed to diversity shifts in some mammals1,2,3,4,5,6,7, previous research often assumed that climate change is invariable across species ranges. We are therefore still ignorant of the true rates of climate change experienced by species assemblages over the last millennia, their impacts on intraspecific diversity, and how they compare to future climate change projections. Here, we use more than 9,000 Late Quaternary records, including fossils and ancient and modern DNA sequences, millennial-scale paleoclimatic reconstructions over the last 50,000 years and future climate change projections to document rates of climate change velocity and dynamics in genetic diversity experienced by an assemblage of 16 extinct and extant Holarctic mammal species. Extinct megafauna experienced velocities more than 15 times faster than the extant species, up to 15.2 km per decade. Notably, extant large-bodied grazers lost almost a 65% of their pool of genetic diversity since the Late Pleistocene, which indicates reduced ability to adapt to on-going global change. Additionally, mammal species experienced overall climate change velocities slower than that projected for the end of the 21st century but punctuated by comparable fast climate change episodes. Our results provide baselines on the impacts of ongoing and future climate change on the diversity of mammal species.

ecology↗

bioRxiv2021

Humans hastened the range collapse and extinction of woolly mammoth

Pathways to extinction start long before the death of the last individual. However, causes of early-stage population declines and the susceptibility of small residual populations to extirpation are typically studied in isolation. Using validated process-explicit models, we disentangle the ecological mechanisms and threats that were integral in the initial decline and later extinction of the woolly mammoth. We show that reconciling ancient DNA data on woolly mammoth population decline with fossil evidence of location and timing of extinction requires process-explicit models with specific demographic and niche constraints, and a constrained synergy of climatic change and human impacts. Validated models needed humans to hasten climate-driven population declines by many millennia, and to allow woolly mammoths to persist in mainland Arctic refugia until the mid-Holocene. Our results show that the role of humans in the extinction dynamics of woolly mammoth began well before the Holocene, exerting lasting effects on the spatial pattern and timing of its range-wide extinction.

ecology↗