Browsing by Author "Bonaccorso, Elisa "

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    Associations among MHC genes, latitude, and avian malaria infections in the rufous-collared sparrow (Zonotrichia capensis)
    (2024) de Aguilar, Juan Rivero; Barroso, Omar; Bonaccorso, Elisa; Cadena, Hector; Hussing, Lucas; Jorquera, Josefina; Martinez, Javier; Martinez-de la Puente, Josue; Marzal, Alfonso; Miranda, Fabiola Leon; Merino, Santiago; Matta, Nubia E.; Ramenofsky, Marilyn; Rozzi, Ricardo; Valeris-Chacin, Carlos E.; Vasquez, Rodrigo A.; Vianna, Juliana A.; Wingfield, John C.
    The major histocompatibility complex (MHC) is a genetic region in jawed vertebrates that contains key genes involved in the immune response. Associations between the MHC and avian malaria infections in wild birds have been observed and mainly explored in the Northern Hemisphere, while a general lack of information remains in the Southern Hemisphere. Here, we investigated the associations between the MHC genes and infections with Plasmodium and Haemoproteus blood parasites along a latitudinal gradient in South America. We sampled 93 rufous-collared sparrows (Zonotrichia capensis) individuals from four countries, Colombia, Ecuador, Peru, and Chile, and estimated MHC-I and MHC-II allele diversity. We detected between 1-4 (MHC-I) and 1-6 (MHC-II) amino acidic alleles per individual, with signs of positive selection. We obtained generalized additive mixed models to explore the associations between MHC-I and MHC-II diversity and latitude. We also explored the relationship between infection status and latitude/biome. We found a non-linear association between the MHC-II amino acidic allele diversity and latitude. Individuals from north Chile presented a lower MHC genetic diversity than those from other locations. We also found an association between deserts and xeric shrublands and a lower prevalence of Haemoproteus parasites. Our results support a lower MHC genetic in arid or semi-arid habitats in the region with the lower prevalence of Haemoproteus parasites.
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    Cost-effective protection of biodiversity in the western Amazon
    (2019) Lessmann, Janeth ; Fajardo, Javier ; Bonaccorso, Elisa ; Bruner, Aaron
    The western Amazon needs to expand its protected-area system to ensure the conservation of its immense and threatened biodiversity. However, potential expansions often meet with resistance because of scarce government resources and competing social priorities. Here, we proposed an expansion of the protected-area system for the western Amazon that increases biodiversity conservation at minimum costs. We started by evaluating biological data to establish conservation targets for enhancing protection of 2419 species of plants and vertebrates. We then built a map that shows the variation in costs of effectively managing lands as protected areas. We also adapted an opportunity cost layer for agriculture and livestock to approximate realistic foregone incomes when a particular extent of land is protected. These cost estimates were used in a decision-support tool to find the most inexpensive places to achieve the conservation targets. We found that this cost-optimized expansion would reduce annual costs by 22% in comparison to an expansion planned without cost data. Moreover, without collaboration with indigenous peoples and without cooperation among the western Amazon countries costs would be 39% and 49% higher, respectively. The cost of the proposed expansion, estimated at US$ 100 million annually, is only a fraction of the regional Gross Domestic Product (0.018%). Thus, this study may help governments and conservation agencies to improve financial planning of the region's reserve network by maximizing species protection at more affordable costs.
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    The performance of protected-area expansions in representing tropical Andean species: past trends and climate change prospects
    (2023) Fajardo, Javier; Lessmann, Janeth; Devenish, Christian; Bonaccorso, Elisa; Felicisimo, angel M.; Rojas-Runjaic, Fernando J. M.; Rojas, Haidy; Lentino, Miguel; Munoz, Jesus; Mateo, Ruben G.
    Protected area (PA) extent has increased significantly over the last 150 years globally, but it is yet unclear whether progress in expanding coverage has been accompanied by improved performance in ecological representation. Here, we explore temporal trends in the performance of PA networks in representing > 16,000 vertebrate and plant species in tropical Andean countries based on species bioclimatic niche modelling. We use a randomization analysis to assess whether representation gains over time (1937-2015) are the expected consequence of increasing the overall area of the network or the result of better designed networks. We also explore the impact of climate change on protected-area representation based on projected species distributions in 2070. We found that PAs added in the last three to four decades were better at representing species diversity than random additions overall. Threatened species, amphibians and reptiles are the exception. Species representation is projected to decrease across PAs under climate change, although PA expansions over the last decade (2006-2015) better represented species' future bioclimatic niches than did sites selected at random for most evaluated groups. These findings indicate an unbalanced representation across taxa, and raises concern over under-represented groups, including threatened species, and species' representation under climate change scenarios. However, they also suggest that decisions related to locating protected areas have become more strategic in recent decades and illustrate that indicators tracking representativeness of networks are crucial in PA monitoring frameworks.