Language Change
(final version)

Access to previous stages of any language shows us that language is always changing. (We can gain this access through written texts or audio recordings, which now give us the possibility of comparing many of today's spoken languages with the way they were spoken many decades ago.) Indeed, if language did not change, we would all still be speaking the same original language that first evolved among our ancestors some 50 millenia (or so) ago. Since language is constantly changing, when the people who have previously spoken one language split up and move apart, the previously united language will also begin to show differences between the new "branches". After a few hundred years, clear differences can be observed, although communication will still be possible and the new speech varieties are said to be mutually intelligible. After a few millenia, however, they will have evolved into separate languages that are no longer mutually intelligible.

Is change problematic?

Yes! On three counts. First, it is a problem for linguists to try to explain, and much of this lecture and the next will deal with how linguists have sought to understand it.

Second, although it used to be thought that because language change is always going on, its very normalcy must mean that it happens without impeding communication, we now know that this is not the case. Linguists thought that the redundancy that is a normal part of language would serve to make communication unproblematic even during language change. We now know that change can impede communication, especially under conditions of "noise", when people don't have as much redundancy to help them understand.

A third observation about language change is that, when people realize that it is happening, they usually react negatively, feeling that the language has "gone down hill", or has deteriorated. You never seem to hear older people commenting that the language of their children or grandchildren has improved as compared with the state of the language when they were young!

Language change seems even more puzzling, given that it hampers communication, and that people object to it.

Why does language change?

A standard answer in linguistics is that language is transformed progressively as it is transmitted from one generation to the next - the idea being that as each generation must re-create the grammar from the input received from parents, older siblings and other members of the speech community, something gets altered. The grammars any new generation devises will be based on the output from speech generated by the mature grammars of previous generations of native speakers, however these grammars may differ due to ambiguities in the input that allow for different solutions, or due to some sort of skewing in the data received. From a systems perspective, it has been argued that it might simply be a question of entropy, that linguistic systems are so complex that it would take too much energy to make sure that every person's grammar was identical in every detail. However, even if the "lost in the transmission" view of language change represents part of the truth, it still does not answer the question of why or how language changes.

Another line of explanation lies in considering how the transmission of language is mediated by social forces. For one thing, children acquire language based on the input of many speakers, and these speakers may well have different linguistic systems based on their own different linguistic histories. It is well established in phonology that children whose parents have foreign accents acquire the variety of the language spoken by the native-speaker community around them rather than the foreign accent of their parents. This also holds across dialect boundaries: the child growing up in Atlanta whose parents come from Maine will end up speaking like an Atlantan. The implication of this is that children are formulating their linguistic systems over a period of years, and input from later in childhood (when they hear more from peers than from parents) has an important effect.

A further aspect of how language change is mediated by social forces takes us out of the area of primary acquisition altogether: when we observe how language is used, we discover that people do not speak exactly the same way across all the occasions they have to use language. In particular, expressivity, the conveying of formality and informality, and the expression of intimacy and social distance seem to influence how speakers deploy their linguistic resources. Intimacy, associated with minimizing social distance, seems almost iconically to be associated with minimizing the linguistic signal: rapid speech and the concomitant truncation processes mentioned by Crystal: assimilation, dissimilation, syncope and apocope (these are only some of the processes of sound change Crystal discusses -- we will look at the whole set a little later on today).

Expressivity leads to some vocabulary replacement, often via the constantly renewed slang vocabulary; formality may lead to the borrowing of words from literary language or even from high status foreign languages.

Other theories that have been advanced to explain language change include the "least effort" theory by which sloppy pronunciation in rapid speech causes sound change; the "emulate the upper class" theory according to which the masses copy the upper class, which changes once it has been copied in order to remain socially distinct; and the theory that change is led by the least educated members of society who are the least influenced by the conservative force of the standard language, including the written language. Work of the past three decades in approximately a dozen cities around the world has shown, however, that ongoing language change in the sound system of language is usually led by people who are neither at the top nor the bottom of the social ladder: people who can often be best described as "lower middle class". Another fact about language change, clearly established on the basis of approximately 100 studies, is that women are usually a generation ahead of men in sound change.

Change as diffusion

It is important to remember that, just as an individual genetic change does not change the species unless it is inherited and passed on, language does not change if only one person makes a change in their linguistic inventory or grammar. Unless other people begin to do the same thing, and pass it on to younger speakers, that "mutation" will die as the individual innovative speaker dies. In the preceding discussion, we saw that particular socially-defined groups of people may be "ahead" of others in the diffusion of a sound change through a community.

Sources of language change

Linguists normally distinguish internal and external sources of change in language: internal meaning changes that occur within the language itself (the kinds of changes we have been discussing so far); external changes meaning elements introduced from other languages. These sources may interact, as small changes introduced from outside may cause a ripple effect that ends up altering other aspects of the borrowing language.

What changes in language?

I. Words can change in various ways. A word can be replaced by another word (thus Latin caput 'head' was replaced in Old French by the slang usage of the word testa 'cup' to mean head. Testa eventually lost its slang connotation and became the normal word for 'head' in French (now la tete ). Some words have been replaced because they may be homonymous with taboo words that people avoid: this is cited in a major textbook on historical linguistics as the reason that rooster has largely replaced cock in American English. Other words, of course, drop out of languages subsequent to cultural change that renders their referents obsolete. This would apply, for example, to technologies that have been replaced by other technologies. To the generation whose music is mainly on CD's, a record player may still have some meaning, but words like victrola and gramophone are unknown to today's children.

Words can also change their meaning. Crystal mentions six types of semantic change, which we'll repeat here with different examples:

Extension. Modern English board , originally a plank of wood, had already come to be used for 'table' before it was again extended to refer to the people who sit around the table (as in 'Board of Governors'), or the food that is served on the table (as in 'Bed and Board').

Narrowing. Though most of us learn in school that English animal includes all life forms that are not plants , we generally use it to refer to a much narrower range: the four-footed animals .

Shift. Modern English silly derives from OE saelig, meaning 'happy, blessed, blissful'.

Figurative use. Very tall buildings are called skyscrapers.

Amelioration. Old English cniht 'servant' became Modern English knight, which refers to a nobleman.

Pejoration. A villain once simply meant 'belonging to the villa', and referred to people now usually called 'peasants'.

New words may be also be formed by productive word formation processes, as we discussed in the morphology lecture. One process of particular interest is the formation of new close-class lexical items from open-class lexical sources. For example, the English future auxiliary shall developed out of a main verb which meant 'to owe' (markers of obligation often develop into futures). The French pronoun on 'one' is derived from the Latin homo 'man'.

II. Morphemes may be worn away as a product of phonological change. Old English nouns had endings distinguishing four cases (nominative, accusative, dative and genitive), and this case system was lost (except for the genitive) mainly because of sound changes that led to the dropping of vowels and nasals in final syllables.

The most well-known change process that affects morphology is known as analogy. Analogy seems to operate within paradigms, where people created regularities across word classes that have historically been different. The regularization of English past tense to the -ed suffix is one well known example, as is the replacement of OE -en plurals by -s . Only a few -en plurals are left in some high-frequency words like children , but even here, we can often observe young learners analogizing when they create forms like childs and sheeps.

III. Syntax is almost undiscussed by Crystal in his section on language change, and this is surely in large part because it is one of the newest fields in linguistic research. We are fortunate at Penn in having Dr. Anthony Kroch , an international leader in this field, on our faculty, and the work of Kroch and his colleagues in historical syntax is only now beginning to be incorporated into the broader understanding of language change. Since an appreciation of what is involved in syntactic change demands a more extensive knowledge of syntax than the very brief introduction we've been able to give you in this class, we'll also limit the discussion of this topic to mentioning one example. The model of syntactic change that Kroch has introduced is that of competing grammars, the idea being that much as with the introduction of a new lexical item, the new word competes with the old over a period of time, in the case of syntax too, an innovation can compete with the older rule. Sometimes this can take several centuries to resolve itself. One major change that happened in English between about 1400 and 1700 was the introduction of "do-support", or the use of the verb do as an auxiliary with questions and negation. In Shakespeare's Othello, we find the following line:

"He that filches from me my good name robs me of that which not enriches him."

Today, we would have to say: "which does not (or doesn't ) enrich him".

As with the other auxiliaries ( have and be), when an auxiliary verb is used, that is the verb that is inflected (does), and the former enriches becomes the uninflected enrich.

There are many complex and quite abstract arguments involved in Kroch's explanation of this change, but even without going into them, we can see that the "competing grammar" model allows for competition between either internally-generated or externally derived elements: in other words, the model is neutral as to whether the innovation comes from within the system, or from contact with another dialect or language.

IV. Sounds change in a number of ways, and sound change is one of the most well understood aspects of language change, thanks to the long history of work in comparative/historical linguistics, and also to the research on sound change in progress by another member of the Penn linguistics faculty, Dr. Bill Labov.
There are two kinds of distinctions to be made in considering sound change: first, all sound changes can be described as either conditioned and unconditioned sound change. Unconditioned sound is just that: the old sound becomes a new sound across the board. Such a change occurred in Hawai'ian, in that all the "t" sounds in an older form of the language became "k"s: at the time Europeans encountered Hawai'ian, there were no "t"s in it at all, though the closely related languages Tahitian, Samoan, Tongan and Maori all have "t"s. Another unconditioned sound change that occurred between Middle and Early Modern English (around Shakespeare's time) is known as the Great Vowel Shift. At that time, there was a length distinction in the English vowels, and the Great Vowel Shift altered the position of all the long vowels, in a giant rotation. Long vowels can easily be diphthongized, and that is what happened to the two high vowels: the front "long i" /i:/, and the back "long u" /u:/. The nucleus of these vowels started to drop, and the high position was retained only in the offglide. Eventually, the original /i:/ became /ai/ - so a "long i" vowel in Modern English is now pronounced /ai/ as in a word like 'bite': /bait/. Similarly, the "long u" found its nucleus dropping all the way to /au/: the earlier 'house' /hu:s/ became /haus/. All the other long vowels rotated, the mid vowels /e:/ and /o:/ rising to fill the spots vacated by the former /i:/ and /u:/ respectively, and so on. That is why the modern pronouns 'he' and 'she' are written with /e/ (reflecting the old pronunciation) but pronounced as /i/. In the following chart, the words are located where their vowel used to be pronounced -- where they are pronounced today is indicated by the arrows.

The other kind of regular sound change is called a conditioned sound change. In these cases, change in one sound is conditioned by some adjacent sound. The voicing of voiceless consonants when followed by vowels, and the other side of the coin: the devoicing of voiced consonants when followed by nothing -- can be seen in such phenomena as the Modern English voicing of the -s suffix on words like toys (pronounced as /toyz/, ) or the Modern German devoicing in words like Hund 'dog' (pronounced as /hunt/. ) We know that if a German speaker were to acquire a new noun, *Blug , it would be pronounced as /bluk/ in the singular. With a following vowel added to created the plural suffix, or other endings due to case, it would re-emerge as /bluge/, /blugen/, etc. The point here is that the sound change affected all voiced sounds in final position -- other d's, g's, etc. were unaffected, so that a word that originally began with a /d/ still begins with a /d/. Only final d's were affected, but all final d's were affected -- conditioned sound changes are still very regular.

Another dimension along which we can look at sound change is by classifying changes according to the particular process involved. These processes are listed by Crystal on p. 330, and we will run through them here again with different examples.

Assimilation, or the influence of one sound on an adjacent sound, is perhaps the most pervasive process. Assimilation processes changed Latin /k/ when followed by /i/ or /y/, first to /ky/, then to "ch", then to /s/, so that Latin faciat /fakiat/ 'would make' became fasse /fas/ in Modern French (the subjunctive of the verb faire 'to make'). Another example of assimilation would be the devoicing of German voiced final segments described above -- in this case you would have to say that they are "assimilating" to the lack of voicing when followed by nothing.
In contrast to assimilation, dissimilation, metathesis, and haplology tend to occur more sporadically, i.e., to affect individual words. Dissimilation involves a change in one of two 'same' sounds that are adjacent or almost adjacent in a particular word such that they are no longer the same. Thus the first "l" in English colonel is changed to an "r", and the word is pronounced like "kernel". Metathesis involves the change in order of two adjacent sounds. Crystal cites Modern English third from OE thrid , and Modern English bird is a parallel example. But Modern English bright underwent the opposite change, its ancestor being beorht, and not all "vowel + r" words changed the relative order of these segments as happened with bird and third . Already by the time of Old English, there were two forms of the word for "ask": ascian and acsian. We don't know which form was metathesized from the other, but we do know that acsian won out in the standard language. Haplology is similar to dissimilation, because it involves getting rid of similar neighboring sounds, but this time, one sound is simply dropped out rather than being changed to a different sound. An example is the pronunciation of Modern English probably as prob'ly.

The other processes mentioned by Crystal are merger, split, loss, syncope, apocope, prothesis, and epenthesis. Merger and split can be seen as the mirror image of each other, however mergers are much more common than splits. You might well ask why, if this is the case, there has not been a steady decrease in the number of sounds languages have in their inventories? The answer is that new distinctions are introduced through processes other than splits. A merger that is currently expanding over much of the United States is the merger between "short o" stock, and "long open o". The following table contains examples of words that you probably pronounce differently if you are from the Philadelphia - New York - New England area, or if you are from the South. If you are from Canada, or from California, you probably find that the vowels in these pairs sound the same, rather than different. If this is the case, you have a merger here.

Short "o" Long "Open o"

Splits are rarer than mergers, and usually arise when a formerly conditioned alternation (like the German devoicing discussed above) loses the environment that provided the original conditioning, and the previously conditioned alternation becomes two independent sounds that contrast with each other. This is basically what happened when /f/ and /v/ split in English (/v/ having previously been an alternate of /f/ when /f/ occurred in an intervocalic position).

Loss involves the loss of a sound from a language, as when Hawai'ian lost the /t/ in favor of /k/ (see below).

Syncope and apocope are the loss of medial and final sounds respectively. Middle English 'tame' in the past tense was /temede/. It lost both its medial and final vowels to become Modern English /teymd/. These are usually conditioned changes that do not involve loss of the same sound elsewhere.

Prothesis and epenthesis are the introduction of additional sounds, initially and medially respectively. The addition of the /e/ that made Latin words like scola 'school' into Portuguese escola is the only example of prothesis in foure historical linguistics textbooks I consulted. As for epenthesis, an example other than the one Crystal cites was the /d/ inserted into ME thunrian to give us the Modern English thunder.

How do we know how languages are related?

Linguists rely on systematic sound changes to establish the relationships between languages. The basic idea is that when a change occurs within a speech community, it gets diffused across the entire community of speakers of the language. If, however, the communities have split and are no longer in contact, a change that happens in one community does not get diffused to the other community. Thus a change that happened between early and late Latin would show up in all the 'daughter' languages of Latin, but once the late Latin speakers of the Iberian peninsula were no longer in regular contact with other late Latin speakers, a change that happened there would not spread to the other communities. Languages that share innovations are considered to have shared a common history apart from other languages, and are put on the same branch of the language family tree.

Words in two or more daughter languages that derive from the same word in the ancestral language are known as cognates. Sound changes work to change the actual phonetic form of the word in the different languages, but we can still recognize them as originating from a common source because of the regularities within each language. For example, a change happened in Italian such that in initial consonant clusters, the l that originally followed p and f changed to i. Thus Italian words like fiore 'flower'; fiume 'river'; pioggia 'rain'; and piuma 'feather' are cognates with the French fleur; fleuve; pluie; and plume, respectively, and with Spanish flora, fluvial (adj. 'riverine'); lluvia (by a later change); and pluma respectively.

In the Romance languages below, the word for 'mother' is a cognate in all the six contemporary languages considered, however the word for 'father' is a cognate only in four of the five: in Rumanian, the original word inherited from Latin pater has been replaced by a completely different word, tata.

Spanish and Italian are the only two that retain a phonological reflex of the original Latin medial consonant t, (in both languages, it has been voiced to d, probably a change that occurred in the common ancestor to all the dialects and languages of the Iberian peninsula. All the other Romance languages have dropped it. The original r has also suffered different fates: however, within each language, the same thing happened in both words. Where we find r deleted in final position in the word for 'mother', we also find it deleted in the same position in the word for 'father'.


French Italian Spanish Portuguese Rumanian Catalan
mother mer madre madre mae mama mare
father per padre padre pae tata pare

The same principles are applied in languages that do not have a written history. Several cognate sets in five languages of the Polynesian family are listed in the next table.


Tongan Maori Samoan Tahitian Hawai'ian
1. bird manu manu manu manu manu
2. fish ika ika i?a i?a i?a
3. to eat kai kai ?ai ?ai ?ai
4. forbidden tapu tapu tapu tapu kapu
5. eye mata mata mata mata maka
6. blood toto toto toto toto koko

We see that no changes happened in the nasal consonants, nor in the vowels, but we can observe in lines 2 and 3 that wherever Tongan and Maori have /k/, Samoan, Tahitian and Hawai'ian appear to have /?/ (glottal stop). Apparently there has been an unconditioned change from /k/ to /?/ in the Eastern branch, or a change from /k/ to /k/ in the Western branch of this family. We choose the first as more likely, partly because /t/ is a more common phoneme in the world's languages, partly because backing of consonants is more common than fronting, and partly because of what we know about the culture history: Polynesia was peopled from west to east, and if the change had occurred in the Western branch, that would have been at a time when all five languages were still one speech community. Next, we see in lines 4 - 6 that there is a systematic correspondence between /t/ in the first four languages and /k/ in the easternmost, Hawai'ian. This looks like another systematic, unconditioned sound change, this time in only one language. (We can see from this example that when English borrowed the Polynesian word for "forbidden", we borrowed it from one of the languages west of Hawaii -- we say "taboo", not "kaboo"). This is what a family tree of the five Polynesian languages would look like, based on the small data set above (the picture is somewhat more complex when we look at other cognate sets -- Maori in particular is probably not correctly placed in this diagram, which has been designed as an illustration of the method):

What are the results of language change?

When accompanied by splits of populations, language change results first in dialect divergence (the kinds of differences we see between British and American English; between the French of France and of Quebec; between New World and Old World Spanish and Portuguese). Over longer time periods, we see the emergence of separate languages as in the contemporary Romance languages, separated by about 2000 years, and the Germanic languages, whose divergence began perhaps 500 years earlier. Both of these families are part of Indo-European , for which the Ethnologue web page lists 425 languages! Though political considerations often intervene in whether a particular speech variety is considered to be a language or a dialect, the basic idea behind linguistic classifications is that dialects are mutually intelligible, whereas languages are not.

Of course, the question of intelligibility is always relative. We discovered in class that the following phrases taken from the spontaneous speech of Chicagoans recorded in the early 1990s were difficult for many of us to understand correctly. In the "gating" experiments designed to test cross-dialectal comprehension in American English, subjects first heard a word, then a slightly longer segment, then a whole phrase or sentence that may have disambiguated the original mishearing. These experiments were part of the research project on Cross-Dialectal Comprehension done at the Linguistics Lab here at Penn (for more information on the Northern Cities Shift, see "The Organization of Dialect Diversity" on the home page of the Phonological Atlas of North America .)

Original segment Many people misheard as First expansion Second expansion
drop ??? (nonsense word containing vowel in "that") massive drop
the plane was steady for a while and then it took a massive drop
socks sacks y'hadda wear socks y'hadda wear socks, no sandals
block black one block old senior citizens living on one block
met mutt they met my parents went to Cuba and that's where they met
steady study steady for a while the plane was steady for a while and then it took a massive drop
head* had shook 'er head this woman in while, who just smiled at her and shook 'er head
* Note - this example is not the same as the one we heard in class, but the vowel mismatch is the same.

These misunderstandings are based on the fact that the Chicago speakers (along with 40 - 50 million other people in the "Inland North" dialect including Rochester, Buffalo, Detroit, Syracuse, and other cities of that region) have a rotation of their short vowels such that the low unrounded vowel of the "short o" words like drop, socks, block, and hot is being fronted to the position where other American dialects have words like that, hat, black, rap, and sacks, , and where "short e" words like met, steady and head can sound like mutt, study and thud or mat, static and had.

The Ethnologue data base includes more than 6700 languages spoken in 228 countries. They state that their "criterion for listing speech varieties separately is low intelligibility, as far as that can be ascertained."

How far back can we go?

Most linguists agree that our methods for reconstruction will take as only as far back as about 5000 - 7000 years; after that, the number of cognate sets available for reconstruction becomes just too low to give results other than chance. Many of us feel it would be very satisfying to be able to link up some of the existing families at a higher level, however we do not feel that the evidence allows us to do so. A minority of scholars, however, argue that this is possible, and one particularly well-known group of such scholars goes by the name of Nostraticists, derived from their views that there exists a super-family of language they have called the "Nostratic". A New York Times article from 1995 presents a well-balanced view of the Nostraticist position. Dr. Donald Ringe of the Penn Linguistics Department, himself an expert on the ancient Indo-European language Tocharian, is one of the chief critics of the Nostraticist position, and was seen doing just this on a Nova show a couple of years ago.