Bright (1957), in his Karok grammar (p. 39), cites an example of morphemization in progress. In Karok there is a general phonological rule that the initial consonant of a monosyllabic stem is geminated when in intervocalic position. However, in some themes the initial consonant of such a stem freely varies between being geminated and non-geminated. This variation is evidence of a wavering of the theme between polymorphemic and monomorphemic status.
Source: wiktionary