2026-04-17T23:45:01Zhttps://recercat.cat/oai/request

oai:recercat.cat:10230/439202025-12-12T01:38:02Zcom_2072_6col_2072_452952

00925njm 22002777a 4500 dc Gelabert Xirinachs, Pere, 1991- author Serres Armero, Aitor, 1992- author de Manuel, Marc author Renom, Pere author de Dios, Toni author Ferrando-Bernal, Manuel, 1990- author Navarro i Cuartiellas, Arcadi, 1969- author Marquès i Bonet, Tomàs, 1975- author Lalueza Fox, Carles, 1965- author 2020-03-17T09:03:26Z 2020-03-17T09:03:26Z 2020 As the only endemic neotropical parrot to have recently lived in the northern hemisphere, the Carolina parakeet (Conuropsis carolinensis) was an iconic North American bird. The last surviving specimen died in the Cincinnati Zoo in 1918 [1]. The cause of its extinction remains contentious: besides excessive mortality associated to habitat destruction and active hunting, their survival could have been negatively affected by its range having become increasingly patchy [2] or by the exposure to poultry pathogens [3, 4]. In addition, the Carolina parakeet showed a predilection for cockleburs, an herbaceous plant that contains a powerful toxin, carboxyatractyloside, or CAT [5], which did not seem to affect them but made the birds notoriously toxic to most predators [3]. To explore the demographic history of this bird, we generated the complete genomic sequence of a preserved specimen held in a private collection in Espinelves (Girona, Spain), as well as of a close extant relative, Aratinga solstitialis. We identified two non-synonymous genetic changes in two highly conserved proteins known to interact with CAT that could underlie a specific dietary adaptation to this toxin. Our genomic analyses did not reveal evidence of a dramatic past demographic decline in the Carolina parakeet; also, its genome did not exhibit the long runs of homozygosity that are signals of recent inbreeding and are typically found in endangered species. As such, our results suggest its extinction was an abrupt process and thus likely solely attributable to human causes. This work was supported by ERC Consolidator Grant 681396 “Extinction Genomics” to M.T.P.G. and M.S.-V., Obra Social ‘‘La Caixa’’ and Secretaria d’Universitats i Recerca (GRC2017-SGR880) to T.M.-B. and C.L.-F., BFU2017-86471-P and PGC2018-101927-B-I00 from MINECO/FEDER, UE to T.M.-B, and PGC2018-095931-B-100 from MINECO/FEDER, UE to C.L.-F. T.M.-B. is also supported by a U01 MH106874 grant and Howard Hughes International Early Career and CERCA Programme (Generalitat de Catalunya). A.A. is partially supported by the Strategic Funding UID/Multi/04423/2019 through national funds provided by the Portuguese Foundation for Science and Technology (FCT) and the European Regional Development Fund—program PT2020, by the European Structural and Investment Funds—Competitiveness and Internationalization Operational Program-COMPETE 2020, and by National Funds through the FCT under the project PTDC/CTA-AMB/31774/2017(POCI-01-0145-FEDER/031774/2017) Genòmica Extinció (Biologia) Ornitologia Genètica de poblacions Alimentació Evolutionary history, genomic adaptation to toxic diet, and extinction of the Carolina Parakeet