Proto-Indo-European (PIE)

PIE refers to the putative ancestor of the Indo-European language family, or to our reconstruction of it. There is no clear agreement on exactly where or when the speakers of PIE lived, but a fairly popular theory places them at approximately 3000-4000 BC in what is currently the Russian steppe north of the Black Sea.

PIE is usually reconstructed as having had three series of stop consonants (traditionally voiced, voiceless, and breathy-voiced or "voiced aspirated" i.e. /p b bh/) and either four or five places of articulation (labial, dental, possibly palatal, velar and labiovelar). There was at least one fricative: /s/. The sonants /r l m n j w/ had consonantal and vocalic allophones depending on context eg. *bhero "I bear" with consonantal /r/ versus *bhrtos "borne" with /r/ forming the syllabic nucleus. The basic vowel was /e/, which occurred for instance in the present tense of many verbs. The vowel /o/ occurred typically in the perfect tense, and lengthened forms of these two vowels occurred in a few other contexts. There seem to have been three "laryngeal" consonants in PIE also, which may have been fricatives pronounced deep in the throat (often written /h1 h2 h3/). These had an influence on neighbouring vowels, giving rise to the /a/ and remaining long vowels visible in most early descendants of PIE; however, the laryngeals themselves have vanished in all branches except Anatolian.

PIE seems to have been a highly-inflecting language, with eight noun cases, three genders, three numbers (singular, plural and dual), and several tenses, moods and voices (the exact number is disputed). Reconstruction of its syntax is highly controversial. A substantial lexicon can however be reconstructed: typically basic vocabulary (which survives well into the descendant languages) eg. *h1ed- "eat", *gweh3us "cow", *ph2te:r "father", *kwetwo:r "four", *newos "new".

The break-up of the PIE speech-community

The early branching order of the immediate descendants of PIE is largely indeterminate. A theory popular in previous years was that of a centum-satem initial split, based largely on a distinction in the realisation of palatal stops in different sub-families: in more western branches (Italic, Celtic, Germanic, Greek) they seem to merge with original velars; in more eastern branches (Indo-Iranian, Balto-Slavic, Armenian) the original velars merge with the labiovelar series, while the palatals become sibilants and affricates eg. Latin centum, Avestan satem "hundred". However, this neat division was obscured by the more recent discovery and decipherment of Tocharian and Anatolian, which are centum varieties, but located in the east of the Indo-European family.

The discovery of Anatolian also prompted the suggestion that the first split in the family might have been between Anatolian and the rest of Indo-European, making an Indo-Hittite family. This claim is largely based on the simplicity of the Hittite grammatical system compared with that of Sanskrit and Greek, which may represent an earlier system elaborated on in the ancestor of the Indo-European branch. However, Hittite may rather have undergone substantial grammatical reduction under the influence of neighbouring non-Indo-European languages in Anatolia.

Some theories have also linked Italic and Celtic closely as Italo-Celtic, or Germanic and Balto-Slavic together, or Greek and Armenian; however, the similarities between these groups may well be due to contact rather than common ancestry after the break-up of PIE, or to dialect variations within PIE before its break-up. The linking of Indic and Iranian as Indo-Iranian, and of Baltic and Slavic as Balto-Slavic, seems much more generally accepted, however.

Given these controversies, a relatively neutral presentation of the Indo-European family is as follows: 

       	       	       	Proto-Indo-European   
     ____________________________|_________________________
    |   |     |    |   	|     |    |   	 |     |     |	   |
 Celtic | Germanic | Albanian | Armenian | Tocharian | Phrygian etc.
        |          |   	      |        	 |	     |
      Italic  Balto-Slavic  Greek   Indo-Iranian  Anatolian

References