Biology subjects

Nogues-Bravo, D.

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

8 recordsLinked to original sources

bioRxiv2025

Novel integrated risk index reveals uneven impact of climate change on fascioliasis risk across Africa and Europe

Fascioliasis, a zoonotic parasitic disease caused by the liver flukes Fasciola hepatica and Fasciola gigantica, poses a significant threat to livestock and human health globally. Climate change is altering the transmission dynamics of this disease; however, the direction and magnitude of this change remain uncertain due to a lack of mechanistically grounded predictions at continental scale. In this study, we developed a novel risk index to assess how climate change may affect the potential for fascioliasis transmission across Africa and Europe. The index integrates the following three components that together capture the environmental requirements for Fasciola transmission: the temperature dependence of the parasite transmission; climatic suitability for the snail intermediate host; and availability of freshwater habitats. To estimate these components, we used data from published experimental studies, thousands of snail occurrence records, and both mechanistic and correlative modelling approaches. We predict that climate change will generally reduce fascioliasis risk across most of the ranges of the two investigated liver fluke species, albeit with marked geographical differences. The transmission risk of F. gigantica is predicted to decrease in the Sahel and West Africa, due to above-optimal temperatures for parasite transmission and climatic suitability for the intermediate hosts. However, risk for F. hepatica transmission is projected to increase in parts of Northern Europe, Scandinavia, and Iceland, where livestock densities are high. We also find that the potential for hybridization between F. hepatica and F. gigantica may decline due to reduced geographic overlap in areas that are highly suitable for transmission. By providing a scalable, ecologically informed framework for predicting fascioliasis risk under climate change, this study lays the groundwork for improved local risk assessment. Our results provide a more nuanced perspective on the potential impact of climate change on fascioliasis transmission, showing that this will be highly uneven across Africa and Europe. Author summaryFascioliasis is a snail-borne, zoonotic disease that affects both humans and livestock, causing major health burden and economic losses worldwide. The liver flukes that cause the disease use freshwater snails as their intermediate hosts. They therefore require aquatic habitats and suitable temperatures to complete their life cycle. Climate change altering these conditions; however, it is unclear how this will affect transmission of liver flukes in the future. Here we develop a new risk index that combines three key environmental factors of importance for liver fluke transmission: how suitable temperatures are for parasite transmission, the climatic suitability for snail hosts, and the availability of water. We mapped current and projected future transmission risk for two main species, Fasciola hepatica and Fasciola gigantica, across Africa and Europe. Different from what has been predicted by earlier studies, our results suggest that transmission risk will decline in across most of the range of both species. This will have particularly big impacts in areas where livestock densities are high, including the Sahel region. In northern Europe, transmission risk increases slightly. This study also provides a modelling framework and novel ecological knowledge that can be used to assess risk of transmission at local and continental scale.

ecology↗

bioRxiv2025

Climate change favours African malaria vector mosquitoes

Malaria, a parasitic disease transmitted by mosquitoes of the genus Anopheles, causes half a million deaths annually, mostly among children in Africa. Climate change is expected to significantly alter malaria transmission, but previous forecasts have placed little emphasis on the varying impacts climate change could have on different mosquito vector species. Using extensive mosquito observation datasets and species distribution modelling, we investigate the climatic preferences of six dominant African malaria vector species and how the environmental suitability for these species across sub-Saharan Africa might change due to climate and land use change. We highlight three species for which environmental suitability is consistently associated with higher malaria prevalence and that might be favoured by climate change. Our projections indicate a substantial increase in areas highly suitable for these vectors, underscoring the urgent need to adapt malaria control strategies to shifting vector distributions driven by climate change.

ecology↗

bioRxiv2024

Gaps in the global protection of terrestrial genetic diversity

In recent decades, increased anthropogenic impact has led to a global decline in genetic diversity. Before the Kunming-Montreal Global Biodiversity Framework (2022), the absence of international consensus on how to directly assess and monitor genetic diversity, hampered large-scale conservation efforts. Scarcity of assessable genetic data has hindered the evaluation of conservation policies in safeguarding genetic diversity. This study presents the first global approach for evaluating the protection of genetic diversity. By examining the global distribution of mammalian intraspecific mitochondrial DNA and protected area coverage, we identify regions with high genetic diversity and insufficient protection coverage, e.g. regions of critical importance for biodiversity in the Brazilian Atlantic Forest. Additionally, we estimate the impact of global change scenarios on genetically diverse regions with a low degree of protection, revealing high vulnerability of areas in Central Africa. Nonetheless, integrating robust analysis into conservation planning remains challenging. Incorporating Macrogenetics into conservation planning holds the potential to reverse biodiversity decline.

ecology↗

bioRxiv2022

Species-specific traits mediate avian demographic responses under past climate change

Anticipating species responses to environmental change is a pressing mission in biodiversity conservation. Despite decades of research investigating how climate change may affect population sizes, historical context is lacking and the traits which mediate demographic sensitivity to changing climate remain elusive. We use whole-genome sequence data to reconstruct the demographic histories of 263 bird species over the past million years and identify networks of interacting morphological and life-history traits associated with changes in effective population size (Ne) in response to climate warming and cooling. Our results identify direct and indirect effects of key traits representing dispersal, reproduction, and survival on long-term demographic responses to climate change, thereby highlighting traits most likely to influence population responses to on-going climate warming. One-Sentence SummaryInteracting traits influence sensitivity of bird population sizes to climate warming and cooling over the past million years.

evolutionary biology↗

bioRxiv2021

Quantifying the scale of genetic diversity extinction in the Anthropocene

More species than ever before are at risk of extinction due to anthropogenic habitat loss and climate change. But even species that are not threatened have seen reductions in their populations and geographic ranges, likely impacting their genetic diversity. Although preserving genetic diversity is key to maintaining adaptability of species, we lack predictive tools and global estimates of genetic diversity loss across ecosystems. By bridging theories of biodiversity and population genetics, we introduce a mathematical framework to understand the loss of naturally occurring DNA mutations within decreasing habitat within a species. Analysing genome-wide variation data of 10,095 geo-referenced individuals from 20 plant and animal species, we show that genome-wide diversity follows a power law with geographic area (the mutations-area relationship), which can predict genetic diversity loss in spatial computer simulations of local population extinctions. Given pre-21st century values of ecosystem transformations, we estimate that over 10% of genetic diversity may already be lost, surpassing the United Nations targets for genetic preservation. These estimated losses could rapidly accelerate with advancing climate change and habitat destruction, highlighting the need for forecasting tools that facilitate implementation of policies to protect genetic resources globally.

ecology↗

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↗