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Abstract AimTo better understand the potential impact of climate change on butterfly assemblages across a tropical island, we model the potential for taxonomic and functional homogenization and determine climate‐ and trait‐mediated shifts in projected species distributions. LocationPuerto Rico. MethodsWe used thousands of museum records of diurnal Lepidoptera to model current (1970–2000) and forecast future (2061–2080) species distributions and combined these to test for taxonomic and functional homogenization. We then quantified climatic‐mediated effects on current and forecasted taxonomic and functional composition and, specifically, whether temperature was a primary driver, as predicted by the temperature–size rule and the thermal melanism hypotheses. Finally, we measured wing traits important in thermoregulation (size and colour) and determined trait‐mediated changes in forecasted species distributions over time. ResultsBased on ensemble model outputs, taxonomic and functional richness and turnover were predicted to vary across the island's complex topography. Our models projected an increase in taxonomic and functional richness over time, and a decrease in taxonomic and functional turnover – a signature of biotic homogenization. Under future climate scenarios, models projected a decrease in wing length and an increase in wing brightness at higher elevations. One variable, temperature seasonality, was the strongest predicted driver of both the current spatial distribution and the projected per cent change over time for not only wing traits but also taxonomic and functional richness and turnover. Main conclusionsThe species distribution models generated here identify several priority regions and species for future research and conservation efforts. Our work also highlights the role of seasonality and climatic variability on diverse tropical Lepidoptera assemblages, suggesting that climatic variability may be an important, albeit overlooked, driver of climate change responses.
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This content will become publicly available on May 10, 2026
The Impact of Climate Change on High‐Priority Areas of Conservation for Amphibians in North American Drylands
ABSTRACT AimThe goals of this study were to (1) identify how climate change impacts the distribution of amphibian species and high‐priority conservation areas (HPCA) in the drylands of the Southwest United States and Northern Mexico, (2) describe the relationship between environmental variables and spatial configurations of HPCA and (3) explore how climate change will impact the distribution of HPCA and investigate the relationship between HPCA and protected area (PA) network. LocationSouthwest United States and Northern Mexico. TaxonAmphibians. MethodsWe used distribution maps for 209 amphibian species to estimate surrogates of amphibian diversity, assessed by rarity‐weighted richness (RWR), site importance (Zonation) and species richness. Then, we used species accumulation curves to assess their efficiency in representing amphibians in the least number of sites. Next, we used the most effective surrogate to identify HPCA for amphibians. We used environmental variables, usually related to amphibian distribution, and random forest models to assess the impact of climate on the spatial configuration of HPCA in the current and future times. We also used PA networks to assess their representation. ResultsRWR produced a similar spatial configuration of HPCA as Zonation but could not depict the same level of connectivity. HPCAs were observed mainly across California, central Texas and western Mexico. The spatial distribution of HPCA was mostly influenced by precipitation, temperature and solar radiation. Climate change will influence the future distribution of HPCA. The overlay between HPCA and PA is weak. Main ConclusionClimate change is becoming an ever‐increasing issue for conservation efforts, especially in dryland ecosystems where natural resources are already scarce for native species. Results show an alteration in the spatial configuration of amphibian HPCA, and much is still needed to protect and manage them.
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- Award ID(s):
- 2227233
- PAR ID:
- 10589450
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Biogeography
- ISSN:
- 0305-0270
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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