Browsing by Autor "Max Hidalgo"

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A database of freshwater fish species of the Amazon Basin
(Nature Portfolio, 2020) Céline Jezequel; Pablo A. Tedesco; Rémy Bigorne; Javier A. Maldonado‐Ocampo; Hernán Ortega; Max Hidalgo; Koen Martens; Gislene Torrente‐Vilara; Jansen Zuanon; Astrid Acosta
Beta diversity facets of Amazonian fishes are explained by dispersal limitation, environmental filtering and historical contingencies
(2025) Murilo S. Dias; Céline Jezequel; Bernard Hugueny; Fabien Leprieur; Sébastien Brosse; James S. Albert; Fernanda A. S. Cassemiro; Renata G. Frederico; Max Hidalgo; Hernán Ortega
Identifying the main taxonomic, phylogenetic and trait dimensions of beta diversity, and evaluating their prospective drivers, advances our understanding of patterns and processes involved in the evolution of biological assemblages. Using comprehensiv
Early Biogeography of Otophysi Points to the Neotropics as the Cradle of Characiphysan Fishes
(Wiley, 2025) Achille Lenglin; Max Hidalgo; Guido Miranda; A. Sota; Pierre Caminade; Khalid Belkhir; Olga Otero; Pierre‐Olivier Antoine; Carmen Rosa GARCÍA-DÁVILA; Nicolas Hubert
Freshwaters represent less than 1% of Earth's surface and only 0.02% of the available aquatic habitable volume, yet they host nearly half of the 35,500 known species of bony fishes. Ostariophysan fishes account for 70% of all freshwater fish diversity, comprising approximately 12,000 species across five highly speciose orders. They represent a major evolutionary radiation, the internal phylogenetic relationships of which remain the subject of intense debate. To better understand their early evolutionary history and origin, we reconstructed their phylogeny using dense taxonomic sampling and a combined dataset of complete mitochondrial genomes and sequences from four nuclear genes. Phylogenetic relationships and divergence times were inferred using Bayesian and Maximum Likelihood approaches and molecular dating analyses on a dataset of 687 ostariophysan species, comprising 21,701 aligned positions, including 15,707 variable sites. We also applied model-based Maximum Likelihood ancestral area reconstruction to investigate the early evolutionary history of Otophysi. Our analyses yielded a highly supported phylogenetic hypothesis for Otophysi, highlighting the role of plate tectonics in driving multiple divergence events, along with subsequent range shifts. These findings are further supported by the contraction of the tropical belt, which began at the end of the Cretaceous and continued throughout the Paleogene. Our results support the divergence of Cypriniformes and Characiphysi as a consequence of the breakup of Laurasia and Gondwana. The origin of Characiphysi is traced to West Gondwana, and the subsequent expansion of the group cannot be explained without invoking transcontinental dispersal during the Upper Cretaceous-Paleocene.
Fragmentation of Andes-to-Amazon connectivity by hydropower dams
(American Association for the Advancement of Science, 2018) Elizabeth P. Anderson; Clinton N. Jenkins; Sebastián Heilpern; Javier A. Maldonado‐Ocampo; Fernando M. Carvajal‐Vallejos; Andrea C. Encalada; Juan Francisco Rivadeneira; Max Hidalgo; Carlos Cañas; Hernán Ortega
Andes-to-Amazon river connectivity controls numerous natural and human systems in the greater Amazon. However, it is being rapidly altered by a wave of new hydropower development, the impacts of which have been previously underestimated. We document 142 dams existing or under construction and 160 proposed dams for rivers draining the Andean headwaters of the Amazon. Existing dams have fragmented the tributary networks of six of eight major Andean Amazon river basins. Proposed dams could result in significant losses in river connectivity in river mainstems of five of eight major systems-the Napo, Marañón, Ucayali, Beni, and Mamoré. With a newly reported 671 freshwater fish species inhabiting the Andean headwaters of the Amazon (>500 m), dams threaten previously unrecognized biodiversity, particularly among endemic and migratory species. Because Andean rivers contribute most of the sediment in the mainstem Amazon, losses in river connectivity translate to drastic alteration of river channel and floodplain geomorphology and associated ecosystem services.
The combined effects of climate change and river fragmentation on the distribution of Andean Amazon fishes
(Wiley, 2020) Guido A. Herrera‐R; Thierry Oberdorff; Elizabeth P. Anderson; Sébastien Brosse; Fernando M. Carvajal‐Vallejos; Renata G. Frederico; Max Hidalgo; Céline Jezequel; Mabel Maldonado; Javier A. Maldonado‐Ocampo
Upstream range shifts of freshwater fishes have been documented in recent years due to ongoing climate change. River fragmentation by dams, presenting physical barriers, can limit the climatically induced spatial redistribution of fishes. Andean freshwater ecosystems in the Neotropical region are expected to be highly affected by these future disturbances. However, proper evaluations are still missing. Combining species distribution models and functional traits of Andean Amazon fishes, coupled with dam locations and climatic projections (2070s), we (a) evaluated the potential impacts of future climate on species ranges, (b) investigated the combined impact of river fragmentation and climate change and (c) tested the relationships between these impacts and species functional traits. Results show that climate change will induce range contraction for most of the Andean Amazon fish species, particularly those inhabiting highlands. Dams are not predicted to greatly limit future range shifts for most species (i.e., the Barrier effect). However, some of these barriers should prevent upstream shifts for a considerable number of species, reducing future potential diversity in some basins. River fragmentation is predicted to act jointly with climate change in promoting a considerable decrease in the probability of species to persist in the long-term because of splitting species ranges in smaller fragments (i.e., the Isolation effect). Benthic and fast-flowing water adapted species with hydrodynamic bodies are significantly associated with severe range contractions from climate change.