Nilo-Saharan languages
Blench notes that Kuliak languages do not have extensive internal diversity and clearly had a relatively recent common ancestor. There are many monosyllabic VC (vowel + consonant) lexical roots in Kuliak languages, which is typologically unusual among Nilo-Saharan languages and is more typical of some Australian languages such as Kunjen. Blench considers these VC roots to have cognates in other Nilo-Saharan languages, and suggests that the VC roots may have been eroded from earlier Nilo-Saharan roots that had initial consonants.