|
In linguistics, the cot-caught merger (also known as the low back merger) is a sound change that occurs in some varieties of North American English.
The sound change causes the vowel in words like cot, rock, and doll to be pronounced the same as the vowel in the words caught, talk, law, and small, so that for example cot and caught become homophones, and the two vowel classes become merged as a single phoneme. This sound change appears to have occurred at some time in the nineteenth century. A folk etymology of the expression O.K., which holds that it stands for oll korrect, a joke misspelling of all correct, shows that the merger had begun to take root in North America by the 1830s, when this explanation for the expresion was first attested. The presence of the merger and its absence are both found in many different regions of the continent, and in both urban and rural environments. The precise phonetic value of the merged vowel varies from region to region, as do the phonetic values of the unmerged vowel in regions where the merger has not occurred. Some varieties of North American English still have both the vowels [ɑː] and [ɔː], but [ɔː] is a conditioned variant of /oː/ or /ɑː/ that only occurs before certain sounds, particularly /r/ or /l/, and so it does not count as a separate phoneme.
Generally speaking, merger does not occur in the southern United States, or along the American side of the Great Lakes region. It occurs in most forms of Canadian English west of Quebec, northern New England north of Boston, Massachusetts, and in the Ohio River valley. West of the line formed by the borders of North Dakota down through Oklahoma and in western Texas, the merger is usual. See this map (http://www.ling.upenn.edu/phono_atlas/maps/Map1.html) (external link) for details. The distribution of the merger is complex, even without taking into account the mobility of the American population; there are pockets of speakers with the merger in areas that lack it, and vice versa. There are areas where the merger has only partially occurred, or are in a state of transition. Three phenomena that have been identified as accompanying resistance to the merger are:
- The raising of the "caught" vowel past [ɔ] position
- The presence of the northern cities vowel shift, a chain sound change that affects the pronunciation of several back vowels;
- The presence of certain features of southern American English, and specifically the use of a back upglide for the "caught" vowel. [1] (http://www.ling.upenn.edu/phono_atlas/Atlas_chapters/Ch11/Ch11.html)
For those who have the merger, the two sounds [ɑː] and [ɔː] are allophones; they often do not perceive differences in their usage, hear neither of them as a separate phoneme, and hear the distinct vowels used by speakers whose dialects do distinguish them as variations on the same vowel. They hear the broad A of British English as the same, single vowel sound. But in British English, in particular in Received Pronunciation, there are three sounds distinguished: the long /ɑː/ of cart, the long /ɔː/ of caught, and the short rounded /ɒ/ of cot. The American cot-caught vowels have merged onto what the Briton hears as the vowel of cart.
Media
|
