|Sound change and alternation|
An example occurs in Bambara. Bambara has two phonemic tones, high and low. In this language, the definite article is a floating low tone. With a noun in isolation, it is associated with the preceding vowel, turning a high tone into a falling tone: [bá] river; [bâ] the river. When it occurs between two high tones, it downsteps the following tone:
- [bá tɛ́] it's not a river
- [bá tɛ̄] (or [bá ꜜ tɛ́]) it's not the river
Also common are floating tones associated with a segmental morpheme such as an affix. For example, in Okphela, an Edoid language of Nigeria, the main negative morpheme is distinguished from the present tense morpheme by tone; the present tense morpheme (á-) carries high tone, whereas the negative past morpheme (´a-) imposes a high tone on the syllable which precedes it:
- oh á-nga he is climbing
- óh a-nga he didn't climb
- Clark, Mary M. 1993. "Representation of downstep in Dschang Bamileke". The PhOilOlogy of Tone: The Representation of Tonal Register, ed. by Harry van der Hulst and Keith Snider. Berlin/New York: Mouton de Gruyter. Pp. 29-73
- Mary Paster, UC Berkeley, "FLOATING TONES IN GÃ *" http://elanguage.net/journals/index.php/sal/article/view/1366/925
- Wentum, Comfort. 1997. A Lexical Tonology of Ga. Legon: University of Ghana, M. Phil thesis.
- Clements, G. N. and Kevin C. Ford. 1979. "Kikuyu tone shift and its synchronic consequences." Linguistic Inquiry 10: 179-210.
- Kropp-Dakubu, Mary E. 1986. "Downglide, floating tones and non-WH questions in Ga and Dangme." The Phonological Representation ofSuprasegmentais, ed. by Koen Bogers, Harry van der Hulst, and Maarten Mous. Dordrecht: Foris Publications. Pp. 153-173.
- Zimmerman, 1. 1858. A grammatical sketch and vocabulary of the Akra- or Galanguage with an appendix on the Adanme dialect. Stuttgart, 2 vols. Republished with an Introduction by 1. Berry, Gregg International, 1972.
- Goldsmith, John. 1976. Autosegmental Phonology. Cambridge: MIT, PhD. dissertation. Distributed by IULe.
- Okunor, Vincent. 1969. Tone in the Ga verb. Legon: Institute of African Studies. Paster, Mary. 2000. "Issues in the tonology of Ga." Columbus: Ohio State University, Undergraduate thesis.
- Trutenau, H.M.J. 1972. "A sketch of tone rules required for a generative transformational grammar of Ga (a terraced level tone language)." Linguistics 79: 83-96.