Editing Uto-Aztecan languages (section)

===History of classification===
Uto-Aztecan has been accepted by linguists as a language family since the early 1900s, and six subgroups are generally accepted as valid: [[Numic]], [[Takic languages|Takic]], Pimic, [[Taracahitic languages|Taracahitic]], [[Corachol languages|Corachol]], and [[Nahuan languages|Aztecan]]. That leaves two ungrouped languages: [[Tübatulabal language|Tübatulabal]] and [[Hopi language|Hopi]] (sometimes termed "[[Language isolate|isolates]] within the family"). Some recent studies have begun to question the unity of Taracahitic and Takic and computer-assisted statistical studies have begun to question some of the long-held assumptions and consensuses.  As to higher-level groupings, disagreement has persisted since the 19th century. Presently scholars also disagree as to where to draw language boundaries within the [[dialect continuum|dialect continua]].

The similarities among the Uto-Aztecan languages were noted as early as 1859 by [[J. C. E. Buschmann]], but he failed to recognize the [[genetic (linguistics)|genetic]] affiliation between the Aztecan branch and the rest. He ascribed the similarities between the two groups to diffusion. [[Daniel Garrison Brinton]] added the Aztecan languages to the family in 1891 and coined the term Uto-Aztecan. [[John Wesley Powell]], however, rejected the claim in his own classification of North American indigenous languages (also published in 1891). Powell recognized two language families: "Shoshonean" (encompassing Takic, Numic, Hopi, and Tübatulabal) and "Sonoran" (encompassing Pimic, Taracahitan, and Corachol). In the early 1900s [[Alfred L. Kroeber]] filled in the picture of the Shoshonean group,{{sfn|Kroeber|1907}} while [[Edward Sapir]] proved the unity among Aztecan, "Sonoran", and "Shoshonean".{{sfn|Sapir|1913}}{{sfn|Kroeber|1934}}{{sfn|Whorf|1935}} Sapir's applications of the [[Historical linguistics|comparative method]] to unwritten Native American languages are regarded as groundbreaking.{{citation needed|date=June 2011}} {{Harvcoltxt|Voegelin|Voegelin|Hale|1962}} argued for a three-way division of Shoshonean, Sonoran and Aztecan, following Powell.{{sfn|Steele|1979}}

As of about 2011, there is still debate about whether to accept the proposed basic split between "Northern Uto-Aztecan" and "Southern Uto-Aztecan" languages.{{sfn|Caballero|2011}} Northern Uto-Aztecan corresponds to Powell's "Shoshonean", and the latter is all the rest: Powell's "Sonoran" plus Aztecan. Northern Uto-Aztecan was proposed as a genetic grouping by [[Jeffrey Heath]] in {{harvcoltxt|Heath|1978}} based on morphological evidence, and [[Alexis Manaster Ramer]] in {{harvcoltxt|Manaster Ramer|1992}} adduced phonological evidence in the form of a sound law. [[Terrence Kaufman]] in {{harvcoltxt|Kaufman|1981}} accepted the basic division into Northern and Southern branches as valid. Other scholars have rejected the genealogical unity of either both nodes or the Northern node alone.{{sfn|Goddard|1996|p=7}}{{sfn|Miller|1983|p=118}}{{sfn|Miller|1984}}{{sfn|Mithun|1999|p=539-540}} [[Wick R. Miller]]'s argument was statistical, arguing that Northern Uto-Aztecan languages displayed too few cognates to be considered a unit. On the other hands he found the number of cognates among Southern Uto-Aztecan languages to suggest a genetic relation.{{sfn|Miller|1984}} This position was supported by subsequent lexicostatistic analyses by {{harvcoltxt|Cortina-Borja|Valiñas-Coalla|1989}} and {{harvcoltxt|Cortina-Borja|Stuart-Smith|Valiñas-Coalla|2002}}. Reviewing the debate, {{harvcoltxt|Haugen|2008}} considers the evidence in favor of the genetic unity of Northern Uto-Aztecan to be convincing, but remains agnostic on the validity of Southern Uto-Aztecan as a genetic grouping. {{harvcoltxt|Hill|2011}} also considered the north–south split to be valid based on phonological evidence, confirming both groupings. {{harvcoltxt|Merrill|2013}} adduced further evidence for the unity of Southern Uto-Aztecan as a valid grouping.

{{harvcoltxt|Hill|2011}} also rejected the validity of the Takic grouping decomposing it into a Californian areal grouping together with Tubatulabal.

Some classifications have posited a genetic relation between Corachol and Nahuan (e.g. {{harvcoltxt|Merrill|2013}}). [[Terrence Kaufman|Kaufman]] recognizes similarities between Corachol and Aztecan, but explains them by diffusion instead of genetic evolution.{{sfn|Kaufman|2001|loc=[http://www.albany.edu/anthro/maldp/papers.htm]}} Most scholars view the breakup of Proto-Uto-Aztecan as a case of the gradual disintegration of a dialect continuum.{{sfn|Mithun|1999|p=}}