Abstract
As a result of processes such as habitat loss and overharvest, many species persist in small, isolated populations that experience reduced fitness, decreased evolutionary potential, and increased extinction risk. The goal of species conservation is to restore genetic diversity and adaptive potential caused by isolation and small population size. For populations trapped in an extinction vortex, habitat protection may be inadequate for successful conservation. Alternative actions such as deliberate admixture by introducing individuals from related subspecies may be necessary to recover population fitness. While there is precedent for such actions, admixture temporarily disrupts the taxonomic integrity of a species. Concerns for the taxonomic integrity or “naturalness” of a species may prevent the use of active interventions that involve admixture and transient hybrid gene pools even though extinction may be imminent. We explore the cultural barriers to using tools such as genetic rescue and make suggestions for overcoming those barriers. We focus mainly on examples from animals, but the same evolutionary processes are ongoing in other life forms and are subject to the same cultural barriers.
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Acknowledgements
The ideas in this manuscript benefited greatly from discussions with H. Taylor, N. Dussex, V. J. McKenzie, D. Smith, R. J. Safran, and N. Kane. The EBIO Graduate Writing Co-op patiently edited many drafts and versions.
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Communicated by Dirk Sven Schmeller.
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Love Stowell, S.M., Pinzone, C.A. & Martin, A.P. Overcoming barriers to active interventions for genetic diversity. Biodivers Conserv 26, 1753–1765 (2017). https://doi.org/10.1007/s10531-017-1330-z
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DOI: https://doi.org/10.1007/s10531-017-1330-z