Editing Reindeer (section)

==== Genetic, molecular, and archaeological evidence ====
Meanwhile, [[Genome|genetic data]] continued to accumulate, revealing sufficiently deep divisions to easily separate ''Rangifer'' back into six previously named species and to resurrect several previously named subspecies. Molecular data showed that the Greenland caribou (''R. t. groenlandicus'') and the [[Svalbard reindeer]] (''R. t. platyrhynchus''), although not closely related to each other, were the most genetically divergent among ''Rangifer'' clades;<ref name="Yannic-2013" /> that modern (see [[Reindeer#Evolution|Evolution]] above) Eurasian tundra reindeer (''R. t. tarandus'' and ''R. t. sibiricus'') and North American barren-ground caribou (''R. t. arcticus''), although sharing ancestry, were separable at the subspecies level; that Finnish forest reindeer (''R. t. fennicus'') clustered well apart from both wild and domestic tundra reindeer<ref name="Rozhkov-2020" /> and that boreal woodland caribou (''R. t. caribou'') were separable from all others.<ref name="mtDNA2">{{Cite journal |last1=Cronin |first1=M. A. |last2=MacNeil |first2=M. D. |last3=Patton |first3=J. C. |year=2005 |title=Variation in Mitochondrial Dna and Microsatellite Dna in Caribou (''Rangifer tarandus'') in North America |journal=Journal of Mammalogy |volume=86 |issue=3 |pages=495–505 |doi=10.1644/1545-1542(2005)86[495:VIMDAM]2.0.CO;2 |doi-access=free}}</ref><ref>Cronin, M.A.; MacNeil, M.D.; Patton, J.C. (2006) Mitochondrial DNA and microsatellite DNA variation in domestic reindeer (''Rangifer tarandus tarandus'') and relationships with wild caribou (''Rangifer tarandus granti'', ''Rangifer tarandus groenlandicus'', and ''Rangifer tarandus caribou''). Journal of Heredity 97: 525-530. {{doi|10.1093/jhered/esl012}}</ref> Meanwhile, archaeological evidence was accumulating that Eurasian forest reindeer descended from an extinct forest-adapted reindeer and not from tundra reindeer (see [[Reindeer#Evolution|Evolution]] above); since they do not share a direct [[Common descent|common ancestor]], they cannot be [[Biological specificity#conspecific|conspecific]]. Similarly, woodland caribou diverged from the ancestors of Arctic caribou before modern barren-ground caribou had evolved, and were more likely related to extinct North American forest reindeer (see [[Reindeer#Evolution|Evolution]] above). Lacking a direct shared ancestor, barren-ground and woodland caribou cannot be conspecific.

[[Sequencing|Molecular data]] also revealed that the four western Canadian  montane ecotypes are not woodland caribou: they share a common ancestor with modern barren-ground caribou / tundra reindeer, but distantly, having diverged > 60,000 years ago<ref>McDevitt, A.D.; Mariani, S.; Hebblewhite, M.; Decesare, N.J.; Morgantini, L.; Seip, D.R.; Weckworth, B.V.; Musiani. M. (2009) Survival in the Rockies of an endangered hybrid swarm from diverged caribou (''Rangifer tarandus'') lineages. Molecular Ecology 18: 665-679.</ref><ref name="Horn-2018" /><ref name="Yannic-2013">Yannic, G.; Pellissier, L.; Ortego, J.; Lecomte, N.; Couturier, S.; Cuyler, C.; Dussault, C.; Hundertmark, K.J.; Irvine, R.J.; Jenkins, D.A.; Kolpashikov, L.; Mager, K.; Musiani, M.; Parker, K.L.; Røed, K.H.; Sipko, T.; Þórisson, S.G.; V.Weckworth, B.; Guisan, A.; Bernatchez, L.; Côté, S.D. (2013) Genetic diversity in caribou linked to past and future climate change. Nature Climate Change 4: 132-137. {{doi|10.1038/NCLIMATE2074}}</ref> — before the modern ecotypes had evolved their cold- and darkness-adapted physiologies and mass-migration and aggregation behaviors (see Evolution above). Before Banfield (1961), taxonomists using cranial, dental and skeletal measurements had unequivocally allied these western montane ecotypes with barren-ground caribou, naming them (as in Osgood 1909<ref name="Osgood-1909">Osgood, W.H. (1909) Biological investigations in Alaska and Yukon Territory. US Department of Agriculture Biological survey of North American fauna 1: 1-285.</ref> Murie, 1935<ref name="Murie-1935" /> and Anderson 1946,<ref name="Anderson-1946" /> among others) ''R. t. stonei'', ''R. t. montanus'', ''R. t. fortidens'' and ''R. t. osborni'', respectively,<ref name="Murie-1935">{{Cite book |last=Murie |first=Olaus J. |title=Alaska-Yukon caribou |publisher=United States Department of Agriculture Bureau of Biological Survey Vol. 54 |year=1935 |location=Washington D.C. |pages=1–93}}</ref><ref name="Anderson-1946">{{Cite book |last=Anderson |first=Rudolph M. |title=Catalogue of Canadian Recent Mammals |publisher=National Museum of Canada Bulletin No. 102, Biological Series 31 |year=1946 |location=Ottawa, Ontario |pages=1–238}}</ref> and this phylogeny was confirmed by genetic analysis.