Proto-Dravidian language
Proto-Dravidian is the linguistic reconstruction of the common ancestor of the Dravidian languages. It is thought to have differentiated into Proto-North Dravidian, Proto-Central Dravidian, and Proto-South Dravidian, although the date of diversification is still debated. History. As a proto-language, Proto-Dravidian is not itself attested in historical records. Its modern conception is based solely on reconstruction. It is suggested that the language was spoken in the 4th millennium BCE, and started disintegrating into various branches around 3rd-millennium BCE. The origin and territory of the Proto-Dravidian speakers is uncertain, but some  suggestions have been made based on the reconstructed Proto-Dravidian vocabulary. The reconstruction has been done on the basis of cognate words present in the different branches (Northern, Central and Southern) of the Dravidian language family. According to Dorian Fuller (2007), the botanical vocabulary of Proto-Dravidian is characteristic of the dry deciduous forests of central and peninsular India. For the Southern Dravidians, this region extends from Saurashtra and Central India to South India. It thus represents the general area in which the Southern Dravidians were living before the separation of branches. For Northern Dravidians, the region of their original  abode prior to separation is more obscure, though is regarded by many as the Iran-Pakistan-Afghanistan region. According to Franklin Southworth (2005), the Proto-Dravidian vocabulary is characteristic of a rural economy based on agriculture, animal husbandry and hunting. However, there are some indications of a society more complex than a rural one: This evidence is not sufficient to determine with certainty the territory of the Proto-Dravidians. These characteristics can be accommodated within multiple contemporary cultures, including: Phonology. Vowels. Proto-Dravidian contrasted between five short and long vowels: "*a", "*ā", "*i", "*ī", "*u", "*ū", "*e", "*ē", "*o", "*ō . The sequences *ai" and "*au" are treated as "*ay" and "*av" (or *"aw") Consonants. Proto-Dravidian has been reconstructed as having the following consonant phonemes (Subrahmanyam 1983:p40, Zvelebil 1990, Krishnamurthi 2003): The alveolar stop "*ṯ" developed into an alveolar trill in many daughter languages. The stop sound is retained in Kota and Toda (Subrahmanyam 1983). Malayalam and Sri Lankan Tamil still retains the original (alveolar) stop sound in gemination ("ibid") and after a nasal. In Old Tamil it took the enunciative vowel like the other stops. In other words, "*ṯ" (or "*ṟ") did not occur word-finally without the  enunciative vowel ("ibid"). Velar nasal "*ŋ" occurred only before "*k" in Proto-Dravidian (as in many of its daughter languages). Therefore, it is not considered a separate phoneme in Proto-Dravidian. However, it attained phonemic status in languages like Malayalam, Gondi, Konda and Pengo because the original sequence "*ṅk" was simplified to "*ṅ" or "*ṅṅ" (Subrahmanyam 1983). The glottal fricative "*h" has been proposed by Bh. Krishnamurthi to account for the Old Tamil Aytam ("Āytam") and other Dravidian comparative phonological phenomena (Krishnamurthi 2003). The Northern Dravidian languages Kurukh, Malto and Brahui cannot easily be derived from the traditional Proto -Dravidian phonological system. McAlpin (2003) proposes that they branched off from an earlier stage of Proto-Dravidian than the conventional reconstruction, which would apply only to the other languages. He suggests reconstructing a richer system of dorsal stop consonants: Vocabulary. Crop plants. Below are some crop plants that have been found in the Southern Neolithic complex of Karnataka and Andhra Pradesh, along with their Proto-Dravidian or Proto-South Dravidian reconstructions by Franklin Southworth (2005). In some cases, the proto-form glosses differ from the species identified from archaeological sites. For example, the two Southern Neolithic staple grasses "Brachiaria ramosa  and Setaria verticillata" respectively correspond to the reconstructed Proto-Dravidian forms for "Sorghum vulgare" and "Setaria italica" as early Dravidian speakers shifted to millet species that were later introduced to South India. Basic vocabulary. Basic vocabulary of Proto-Dravidian selected from Krishnamurti (2003):