Wolf taxonomy revisited
by Cat Urbigkit, Pinedale Online!
September 30, 2012
At long last, there has been a comprehensive review of North American wolf taxonomy as reflected in the currently available scientific literature. The review, "An Account of the Taxonomy of North American Wolves From Morphological and Genetic Analyses" was undertaken by U.S. Fish and Wildlife Service employees Steven M. Chambers, Steven R. Fain, Bud Fazio, and Michael Amaral, but does not represent the official views of the agency.
It is also important to note the review "does not evaluate or make any recommendation on whether any subspecies that is found to be valid should be used as a management unit, as the object of management action, or preferred to an alternative legal classification for protection … Suitability of a subspecies as a unit for any of these purposes requires further, separate analysis weighing legal and policy considerations."
In a nutshell, the review concluded:
• The Eastern Gray Wolf (Canis lupus lycaon) is a full species of wolf, not a subspecies.
• The Mexican Wolf (C.l. baileyi) is a subspecies.
• The Northern Timber Wolf (C.l. occidentalis) and the Plains Wolf (C.l. nublilus) are separate and distinct subspecies.
• Wolves in the coastal area of Alaska and British Columbia should be classified in the Plains Wolf subspecies group.
Of interest in terms of the Yellowstone region, Wyoming’s native wolf (previously classified as C.l. irrremotus) and later grouped by taxonomist Ronald Nowak as part of the Plains Wolf subspecies group, was again included in the Plains Wolf grouping in the new review (irremotus became a synonym). The subspecies of wolf reintroduced to Yellowstone in the mid-1990s was from a separate subspecies grouping – the Northern Timber Wolf (C.l. occidentalis).
The researchers noted: "Our understanding of the historical interactions between subspecies or genetically different populations is that they are dynamic processes and boundaries can shift over time. Even with the great dispersal capabilities of wolves and their interaction in these intergrade zones, genetic indications of the independent evolution of the wolves here recognized as species or subspecies are still discernible on a continental scale."
It is also important to note that the authors concede that further research may provide data that would change certain conclusions in the report, and that there are many more historical specimens of wolves in museum and government agency collections that could provide more data for inclusion in future reviews.
Here’s the full abstract:
The available scientific literature was reviewed to assess the taxonomic standing of North American wolves, including subspecies of the gray wolf, Canis lupus. The recent scientific proposal that the eastern wolf, C. l. lycaon, is not a subspecies of gray wolf, but a full species, Canis lycaon, is well-supported by both morphological and genetic data. This species' range extends westward to Minnesota, and it hybridizes with gray wolves where the two species are in contact in eastern Canada and the Upper Peninsula of Michigan, Wisconsin, and Minnesota. Genetic data support a close relationship between eastern wolf and red wolf Canis rufus, but do not support the proposal that they are the same species; it is more likely that they evolved independently from different lineages of a common ancestor with coyotes. The genetic distinctiveness of the Mexican wolf Canis lupus baileyi supports its recognition as a subspecies. The available genetic and morphometric data do not provide clear support for the recognition of the Arctic wolf Canis lupus arctos, but the available genetic data are almost entirely limited to one group of genetic markers (microsatellite DNA) and are not definitive on this question. Recognition of the northern timber wolf Canis lupus occidentalis and the plains wolf Canis lupus nubilus as subspecies is supported by morphological data and extensive studies of microsatellite DNA variation where both subspecies are in contact in Canada. The wolves of coastal areas in southeastern Alaska and British Columbia should be assigned to C. lupus nubilus. There is scientific support for the taxa recognized here, but delineation of exact geographic boundaries presents challenges. Rather than sharp boundaries between taxa, boundaries should generally be thought of as intergrade zones of variable width."
Click on the link below to read the entire report. For those interested in this topic, reading the entire report is highly encouraged.