Genetic load and adaptive potential of a recovered avian species that narrowly avoided extinction

Femerling, Georgette, van Oosterhout, Cock ORCID:, Feng, Shaohong, Bristol, Rachel M., Zhang, Guojie, Groombridge, Jim, Gilbert, M. Thomas P. and Morales, Hernán E. (2023) Genetic load and adaptive potential of a recovered avian species that narrowly avoided extinction. Molecular Biology and Evolution, 40 (12). ISSN 0737-4038

[thumbnail of msad256]
PDF (msad256) - Published Version
Available under License Creative Commons Attribution.

Download (1MB) | Preview


High genetic diversity is a good predictor of long-term population viability, yet some species persevere despite having low genetic diversity. Here we study the genomic erosion of the Seychelles paradise flycatcher (Terpsiphone corvina), a species that narrowly avoided extinction after having declined to 28 individuals in the 1960s. The species recovered unassisted to over 250 individuals in the 1990s and was downlisted from Critically Endangered to Vulnerable in the International Union for the Conservation of Nature Red List in 2020. By comparing historical, prebottleneck (130+ years old) and modern genomes, we uncovered a 10-fold loss of genetic diversity. Highly deleterious mutations were partly purged during the bottleneck, but mildly deleterious mutations accumulated. The genome shows signs of historical inbreeding during the bottleneck in the 1960s, but low levels of recent inbreeding after demographic recovery. Computer simulations suggest that the species long-term small Ne reduced the masked genetic load and made the species more resilient to inbreeding and extinction. However, the reduction in genetic diversity due to the chronically small Ne and the severe bottleneck is likely to have reduced the species adaptive potential to face environmental change, which together with a higher load, compromises its long-term population viability. Thus, small ancestral Ne offers short-term bottleneck resilience but hampers long-term adaptability to environmental shifts. In light of rapid global rates of population decline, our work shows that species can continue to suffer the effect of their decline even after recovery, highlighting the importance of considering genomic erosion and computer modeling in conservation assessments.

Item Type: Article
Additional Information: Funding Information: We are grateful to curators Hein van Grouw from the Natural History Museum, Tring, UK and Michael Brooke from the Museum of Zoology, University of Cambridge, UK. Darwin Initiative grant 15/009 to JG facilitated blood-sampling of the modern population. We are grateful to members of the B10K consortium for their work on the reference genome and Ester Milesi for help processing samples. We thank Shyam Gopalakrishnan and Xin Sun for bioinformatics advice. GF was supported by UNAM-DGECI Iniciación a la Investigación. CvO was funded by the Earth and Life Systems Alliance (ELSA). MTPG acknowledges DNRF143 award for funding. HEM was funded by the European Union's Horizon 2020 Research and Innovation Programme under a Marie Sklodowska-Curie grant (840519) and by the ERC (ERODE, 101078303). Views and opinions expressed are those of the authors only and do not necessarily reflect those of the European Union or the European Research Council. Neither the European Union nor the granting authority can be held responsible for them.
Uncontrolled Keywords: genetic load,historical genomics,adaptive potential,extinction,conservation,biochemistry, genetics and molecular biology(all) ,/dk/atira/pure/subjectarea/asjc/1300
Faculty \ School: Faculty of Science > School of Environmental Sciences
UEA Research Groups: Faculty of Science > Research Centres > Centre for Ecology, Evolution and Conservation
Related URLs:
Depositing User: LivePure Connector
Date Deposited: 07 May 2024 09:32
Last Modified: 09 May 2024 08:30
DOI: 10.1093/molbev/msad256


Downloads per month over past year

Actions (login required)

View Item View Item