Cot–caught merger

The cot–caught merger is a sound change present in some dialects of English where speakers do not distinguish the vowels in "cot" and "caught". Names like "cot–caught merger" and lot–thought merger come from the minimal pairs that are lost as a result of this sound change. The phonemes involved in the cot-caught merger are represented in the International Phonetic Alphabet as /ɒ/ and /ɔ/, respectively. These vowels are both low and back—as can be seen in the IPA chart—and is sometimes referred to as the low back merger. The father-bother merger that spread through North America in the eighteenth and nineteenth centuries has resulted in many dialects having no vowel difference in words like "father", "lot", and "thought".

Overview

IPA: Vowels

	Front	Central	Back
Close	i y	ɨ ʉ	ɯ u
Near-close	ɪ ʏ		ʊ
Close-mid	e ø	ɘ ɵ	ɤ o
Mid	e̞ ø̞	ə	ɤ̞ o̞
Open-mid	ɛ œ	ɜ ɞ	ʌ ɔ
Near-open	æ	ɐ
Open	a ɶ	ä	ɑ ɒ

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Legend: unrounded • rounded

The shift causes the vowel sound in words like cot, nod and stock and the vowel sound in words like caught, gnawed and stalk to merge into a single phoneme; therefore the pairs cot and caught, stock and stalk, nod and gnawed become perfect homophones, and shock and talk, for example, become perfect rhymes. The cot–caught merger is completed in the following dialects:

• Some dialects within the British Isles:
  • All Scottish English accents, towards [ɔ] (without the father–bother merger)
  • Irish English broad and traditional accents, including:
    • Some northern Ulster English including in conservative mid Ulster English towards [ä] and in Ulster Scots English towards [ɔ] (without the father–bother merger)
• Many North American English accents:
  • Several accents of U.S. English, including:
    • Pittsburgh English, towards [ɒ~ɔ] (with the father–bother merger)
    • All New England English towards [ɑ~ɒ] (in Boston and Eastern New England, particularly towards [ɒ] ), except in Rhode Island and southern Connecticut
    • All Western American English (with the father–bother merger)
    • Cajun English towards [ä] .
  • Nearly all Canadian English, including:
    • Standard Canadian English towards [ɒ] (with the father–bother merger)
    • Maritimer and Newfoundland English, towards [ɑ~ä] (with the father–bother merger)
• Some Singaporean English (without the father–bother merger)

Homophonous pairs

/ɑ/ or /ɒ/ (written a, o, ol)	/ɔ/ (written au, aw, al, ough)	IPA (using ⟨ɒ⟩ for the merged vowel)	Notes
bobble	bauble	ˈbɒbəl
bock	balk	ˈbɒk
body	bawdy	ˈbɒdi
bon	bawn	ˈbɒn
bot	bought	ˈbɒt
box	balks	ˈbɒks
chock	chalk	ˈtʃɒk
clod	Claude	ˈklɒd
clod	clawed	ˈklɒd
cock	caulk	ˈkɒk
cod	cawed	ˈkɒd
coddle	caudle	ˈkɒdəl
collar	caller	ˈkɒlə(r)
cot	caught	ˈkɒt
doddle	dawdle	ˈdɒdəl
don	dawn, Dawn	ˈdɒn
dotter	daughter	ˈdɒtə(r)
fond	fawned	ˈfɒnd
fox	Fawkes	ˈfɒks
frot	fraught	ˈfrɒt
god	gaud	ˈɡɒd
hock	hawk	ˈhɒk
holler	hauler	ˈhɒlə(r)
hottie	haughty	ˈhɒti
hough	hawk	ˈhɒk
knot	naught	ˈnɒt
knot	nought	ˈnɒt
knotty	naughty	ˈnɒti
mod	Maud, Maude	ˈmɒd
modeling	maudlin	ˈmɒdlɪn	With G-dropping. Also /ˈmɒdəlɪn/.
Moll	mall	ˈmɒl
Moll	maul	ˈmɒl
nod	gnawed	ˈnɒd
not	naught	ˈnɒt
not	nought	ˈnɒt
odd	awed	ˈɒd
Otto	auto	ˈɒtoʊ
Oz	awes	ˈɒz
pod	pawed	ˈpɒd
pol	Paul	ˈpɒl
pol	pall	ˈpɒl
pol	pawl	ˈpɒl
Poll	Paul	ˈpɒl
Poll	pall	ˈpɒl
Poll	pawl	ˈpɒl
Polly	Paulie, Pauly	ˈpɒli
poly	Paulie, Pauly	ˈpɒli
pond	pawned	ˈpɒnd
popper	pauper	ˈpɒpə(r)
poz	pause	ˈpɒz
poz	paws	ˈpɒz
rot	wrought	ˈrɒt
slotter	slaughter	ˈslɒtə(r)
sod	sawed	ˈsɒd
Sol	Saul	ˈsɒl
squalor	squaller	ˈskwɒlə(r)
stock	stalk	ˈstɒk
tock	talk	ˈtɒk
tot	taught	ˈtɒt
tot	taut	ˈtɒt
tox	talks	ˈtɒks
von	Vaughan	ˈvɒn
wok	walk	ˈwɒk
yon	yawn	ˈjɒn

North American English

On this map of English-speaking North America, the green dots represent speakers who have completely merged the vowels of cot and caught. The dark blue dots represent speakers who have completely resisted the merger. The medium blue dots represent speakers with a partial merger (either production or perception but not both), and the yellow dots represent speakers with the merger in transition. Based on the work of Labov, Ash and Boberg.

Nowhere is the shift more complex than in North American English. The presence of the merger and its absence are both found in many different regions of the North American continent, where it has been studied in greatest depth, and in both urban and rural environments. The symbols traditionally used to transcribe the vowels in the words cot and caught as spoken in American English are ⟨ɑ⟩ and ⟨ɔ⟩, respectively, although their precise phonetic values may vary, as does the phonetic value of the merged vowel in the regions where the merger occurs.

Even without taking into account the mobility of the American population, the distribution of the merger is still complex; 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 is in a state of transition. For example, based on research directed by William Labov (using telephone surveys) in the 1990s, younger speakers in Kansas, Nebraska, and the Dakotas exhibited the merger while speakers older than 40 typically did not. The 2003 Harvard Dialect Survey, in which subjects did not necessarily grow up in the place they identified as the source of their dialect features, indicates that there are speakers of both merging and contrast-preserving accents throughout the country, though the basic isoglosses are almost identical to those revealed by Labov's 1996 telephone survey. Both surveys indicate that, as of the 1990s, approximately 60% of American English speakers preserved the contrast, while approximately 40% merged the phonemes. Further complicating matters are speakers who merge the phonemes in some contexts but not others, or merge them when the words are spoken unstressed or casually but not when they're stressed.

Speakers with the merger in northeastern New England still maintain a phonemic distinction between a fronted and unrounded /ɑ/ (phonetically [ä]) and a back and usually rounded /ɔ/ (phonetically [ɒ]), because in northeastern New England (unlike in Canada and the Western United States), the cot–caught merger occurred without the father–bother merger. Thus, although northeastern New Englanders pronounce both cot and caught as [kɒt], they pronounce cart as [kät].

Labov et al. also reveal that, for about 15% of respondents, a specific /ɑ/–/ɔ/ merger before /n/ but not before /t/ (or other consonants) is in effect, so that Don and dawn are homophonous, but cot and caught are not. In this case, a distinct vowel shift (which overlaps with the cot–caught merger for all speakers who have indeed completed the cot–caught merger) is taking place, identified as the Don–dawn merger.

Resistance

According to Labov, Ash, and Boberg, the merger in North America is most strongly resisted in three regions:

• The "South", somewhat excluding Texas and Florida
• The "Inland North", encompassing the eastern and central Great Lakes region (on the U.S. side of the border)
• The "Northeast Corridor" along the Atlantic coast, ranging from Baltimore to Philadelphia to New York City to Providence (but not to Boston or anywhere north of there).

In these areas, sociolinguists have studied three techniques that speakers use to preserve the contrast. The first was fronting of /ɑ/ found in the Inland North. In this technique, speakers advance the LOT vowel /ɑ/ as far as the cardinal [a] (the open front unrounded vowel). This is also met with the raising of the TRAP vowel /æ/ to [eə] in all instances. (Which vowel triggered which other vowel is still debated.)

The second technique of resistance to the merger is the raising of the THOUGHT vowel /ɔ/ found in the New York City and the mid-Atlantic region's accents. In areas that don't use this technique, sometimes /ɔ/ is pronounced closer to [ɔ̝]. On the contrary, in this technique, either /ɔ/ retains its historical high (raised) value [ɔ], or it is raised even higher to [ɔə⁓oə], or (in the extreme case) even [ʊə].

The third technique is found in the South. This is the result of vowel breaking in Southern American English, where /ɔ/ is broken to [ɒʊ], keeping it distinct from the LOT vowel. Many Southerners, however, are beginning to embrace the merger, particularly Southerners who are younger or urban.

African-American Vernacular English accents have traditionally resisted the cot-caught merger, with LOT pronounced [ä] and THOUGHT traditionally pronounced [ɒɔ], though now often [ɒ~ɔə]. Early 2000s research has shown that this resistance may continue to be reinforced by the fronting of LOT, linked through a chain shift of vowels to the raising of the TRAP, DRESS, and perhaps KIT vowels. This chain shift is called the "African American Shift". However there is evidence of AAVE speakers picking up the cot-caught merger in Pittsburgh and Charleston, South Carolina.

Origin

Theories of the origin of the merger exist, with two competing scenarios. One group of scholars argues for an independent North American development, while others argue for contact-induced language change via Scottish immigrants (e.g. Dollinger 2010), in which a role is afforded to Canadian English, where the spread from East to West was completed more quickly than in the US. Others consider the issue unresolved (Boberg 2010: 199?).

England

In London's Cockney accent, a cot–caught merger is possible only in rapid speech. The THOUGHT vowel has two phonemically distinct variants: closer /oː/ (phonetically [oː ~ oʊ ~ ɔo]) and more open /ɔə/ (phonetically [ɔə ~ ɔwə ~ ɔː]). The more open variant is sometimes neutralized in rapid speech with the LOT vowel /ɒ/ (phonetically [ɒ ~ ɔ]) in utterances such as [sˈfɔðɛn] (phonemically /ɑɪ wəz ˈfɔə ðen/) for I was four then. Otherwise /ɔə/ is still readily distinguished from /ɒ/ by length.

Scotland

Outside North America, another dialect featuring the merger is Scottish English. Like in New England English, the cot–caught merger occurred without the father–bother merger. Therefore, speakers still retain the distinction between /a/ and /ɔ/.

See also

• Phonological history of English low back vowels

Bibliography

• Barber, Charles Laurence (1997). Early modern English (second ed.). Edinburgh: Edinburgh University Press. ISBN 0-7486-0835-4.
• Gordon, Matthew J. (2005), "The Midwest Accent", American Varieties, PBS, retrieved August 29, 2010
• Labov, William; Ash, Sharon; Boberg, Charles (2006). The Atlas of North American English: Phonetics, Phonology, and Sound Change: a Multimedia Reference Tool. Berlin ; New York: Walter de Gruyter. ISBN 3-11-016746-8. {{cite book}}: Invalid |ref=harv (help)
• Wells, John C. (1982), Accents of English, Vol. 2: The British Isles (pp. i–xx, 279–466), Cambridge University Press, doi:10.1017/CBO9780511611759, ISBN 0-52128540-2 

External links

• Map of the cot–caught merger from the 2003 Harvard Dialect Survey
• Map of the cot–caught merger from Labov's 1996 telephone survey
• Description of the cot–caught merger in the Phonological Atlas
• Map of the cot–caught merger before /n/ and /t/
• Chapter 13 of the Atlas of North American English, which discusses the "short-o" configuration of various American accents