{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T13:11:17Z","timestamp":1789132277119,"version":"build-2803163510"},"reference-count":58,"publisher":"Oxford University Press (OUP)","license":[{"start":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T00:00:00Z","timestamp":1787270400000},"content-version":"am","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"funder":[{"name":"US State Department\u2019s Fulbright US Scholar program"},{"DOI":"10.13039\/100005825","name":"National Institute of Food and Agriculture","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100005825","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Sakhalin Energy Investment Company"},{"name":"Exxon Neftegas Limited"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Local extirpations and extreme bottlenecks can deplete genetic variation and obscure population dynamics, especially in highly mobile species. The gray whale (Eschrichtius robustus) undertakes some of the longest known migrations among mammals, and two stocks (eastern and western gray whales) were historically recognized in the Pacific. Commercial whaling depleted both stocks, and although the eastern North Pacific stock has rebounded, the western stock was feared extirpated. In the post-whaling era, the origin of a small summer aggregation near Sakhalin Island, Russia (which we refer to as the western North Pacific stock) is unclear; this group may include descendants from the original western stock, founders from the eastern stock, or some combination of the two. To clarify the genetic affinities of western North Pacific gray whales, we analyzed whole-genome resequencing data for 71 individuals sampled from both geographic regions. Surprisingly, western North Pacific whales are more genetically varied than eastern North Pacific whales according to principal components and admixture analyses. We present evidence that this structure reflects mixed ancestry in the western North Pacific, where some contemporary whales retain ancestry from the feared-extirpated western population, detectable as \u201cghost\u201d introgression, whereas others are of eastern ancestry. Genomic signals based on both single nucleotide polymorphisms and on copy number variants indicate that despite mixed ancestry, the influx of recent eastern gene flow has largely homogenized genomic diversity across the Pacific. These findings highlight the ability of whole-genome data to help resolve questions of extirpation and to clarify complex gene flow dynamics in highly mobile species.<\/jats:p>","DOI":"10.1093\/jhered\/esag059","type":"journal-article","created":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T16:50:49Z","timestamp":1787244649000},"source":"Crossref","is-referenced-by-count":0,"title":["The contemporary Pacific gray whale (\n                    <i>Eschrichtius robustus<\/i>\n                    ) gene pool includes ancestry from a potential ghost population: Inferences from population genomics"],"prefix":"10.1093","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2139-3694","authenticated-orcid":false,"given":"Natalie M","family":"Allen","sequence":"first","affiliation":[{"name":"Department of Forestry and Natural Resources, Purdue University , West Lafayette, IN ,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3364-2064","authenticated-orcid":false,"given":"Anna","family":"Br\u00fcniche-Olsen","sequence":"additional","affiliation":[{"name":"Center for Macroecology, Evolution and Climate, Globe Institute, University of Copenhagen , Universitetsparken 15, Copenhagen ,","place":["Denmark"]},{"name":"Center for Global Mountain Biodiversity, Globe Institute, University of Copenhagen , Universitetsparken 15, Copenhagen ,","place":["Denmark"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2840-8425","authenticated-orcid":false,"given":"Jong Yoon","family":"Jeon","sequence":"additional","affiliation":[{"name":"Department of Forestry and Natural Resources, Purdue University , West Lafayette, IN ,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8294-3533","authenticated-orcid":false,"given":"Andrew J","family":"Mularo","sequence":"additional","affiliation":[{"name":"Department of Integrative Biology , W.K. Kellogg Biological Station, Michigan State University, East Lansing, MI ,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9624-7806","authenticated-orcid":false,"given":"John W","family":"Bickham","sequence":"additional","affiliation":[{"name":"Department of Ecology and Conservation Biology, Texas A&M University , College Station, TX ,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1423-8573","authenticated-orcid":false,"given":"Jorge Urb\u00e1n","family":"R","sequence":"additional","affiliation":[{"name":"Departamento Academico de Ciencias Marinas y Costeras, Universidad Autonoma de Baja California Sur , La Paz, BCS ,","place":["Mexico"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7315-5631","authenticated-orcid":false,"given":"J Andrew","family":"DeWoody","sequence":"additional","affiliation":[{"name":"Department of Forestry and Natural Resources, Purdue University , West Lafayette, IN ,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,8,21]]},"reference":[{"key":"2026091108565081200_ref3","first-page":"227","article-title":"Monograph of the Pacific Cetacea. 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