Regarding the pronunciation samples, please bear in mind that they were prepared by a non-speaker (the author), and are no doubt fairly poor attempts. The late Clifford Wolfe, an Omaha man with whom I worked briefly, described me as sounding "sort of like a Ponca," which I took to be his charitable way of saying "recognizable, but alien." I have not worked with Ponca speakers, but I suspect they might think I sounded Omaha. Trust me, though, it's just a thick American English accent.
Here is the Omaha-Ponca sound system in NetSiouan form
Historical Developments Characteristic of Dhegiha
Unless otherwise indicated, Dhegiha forms cited below are given in Omaha-Ponca form.
A particular development of Dhegiha phonology is the falling together of the stop+stop clusters with the Proto-Siouan preaspirates in a distinctive class of tense or geminate stops termed sonant-surds by Dorsey. Thus a Dhegiha language like Omaha-Ponca has tte' 'buffalo' instead of Dakotan pte' 'buffalo (cow)', and tti' 'to dwell' instead of Dakotan thi'.
Dhegiha does have some aspirates. These also correspond to Dakotan aspirates, or usually h for *th, but the corresponding forms in Ioway-Otoe and Winnebago are unaspirated. It is assumed that these aspirates represent Proto-Siouan postaspirates, as opposed to preaspirates. An example would be Omaha-Ponca thi 'to arrive here', corresponding to Dakotan hi and Winnebago j^ii. (These are bare stems. Motion verbs usually have some additional morphology attached in most contexts.)
Omaha-Ponca is unique in treating Proto-Siouan *W and *R (distinct from *w and *r) as m and n. This produces oppositions between m + nasal vowel (from *wVN) and m + oral vowel (from *WV), and n + nasal vowel (from *rVN) and n + oral vowel (from *RV). For examples of nasal sonorants before oral vowels, cf. Omaha-Ponca me' 'spring' or negi' 'maternal uncle; mother's brother or male descendent of his'. In these contexts Dakotan would have b or w (depending on the dialect) for *W, and d, l, or n (depending on the dialect) for *R.
Dhegiha also has a distinctive battery of developments of *y and *r, especially in clusters. For *y, Omaha-Ponca has z^ as in z^a'be 'beaver', while Dakotan has c^h as in c^ha'pa, and other Siouan languages often have r, having merged *y and *r as r, as in Winnebago ra'ap. For *r Omaha-Ponca has dh as in dhathe' 'to eat (something)'. In some other Dhegiha languages dh develops further into d (Quapaw) or y (Kansa), and there are often other developments in clusters, for example Kansa and Osage treat *kr, which is gdh in Omaha-Ponca, as l. In clusters in Dhegiha *r develops as *R (see above), as in Omaha-Ponca (s^)na'the 'you ate it'.
In the second persons of dh-stem verbs, cf. (s^)na'the just cited, and in the =s^na enclitic, signifying 'exclusively, only, habitually', modern Omaha-Ponca reduces s^n to n. This happened in the late 1800s. Dorsey found the elders using s^n in the 1880s, while younger people used hn or n, n being what I have observed among the Omaha today. I have only interviewed a very few speakers, however. This development parallels the earlier loss of s^ in the second persons of y-stem verbs in Dakotan.
Omaha-Ponca is unique in Dhegiha in reducing both *k? and *x? to ?. So Omaha-Ponca has wa?u' 'woman', where Quapaw has wax?o', and k?i' 'to give (to someone)', where Dakotan has k?u'. Osage and Kansa do reduce *k? and *x? to k?. Hence Osage has wak?o' and k?u' for these forms.
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