Koro Aka Language Documentation Project
Most people of the tribal group known as the Aka of West Kameng and East Kameng districts of Arunachal Pradesh speak a language called ʁuso, written Hruso. But there is also a small sub-tribe of about 800-1200 people that are locally known as the Koro-Aka, who speak an entirely separate language from the Hruso-Aka. Culturally p art of the Aka tribe, the Koro Aka language is a separate and unique language of the Tibeto-Burman family, and not a dialect of the Hruso language (Anderson and Murmu 2010).
As research from Living Tongues Institute for Endangered Languages has shown, Koro is clearly not a part of Hrusish linguistically, which does most likely include the other local language Miji, in addition to Hruso. To be sure, it is clear that Koro Aka is not a variety of Hruso Aka in any sense. In fact, Koro and Miji have at least as many parallels lexically as do Koro and Hruso.
Indeed, there are very few unique Koro-Hruso isoglosses, and in fact little has been borrowed across the languages. However, this may not actually be that surprising if you think about the nature of the relationship between Koro and Hruso. It is precisely different linguistic practices that distinguish the Koro Aka from the Hruso Aka, who are otherwise basically identical culturally, and they both are considered by themselves to be part of the same tribe.
Koro Aka does however share certain lexical and grammatical correspondences with a number of different related languages of Arunachal Pradesh. While Koro Aka does not appear to be a Tani language per se, it does share some notable commonalities with languages of both the Western and Eastern Tani areas, and indeed with Proto-Tani itself (Sun 1993). For example, within Western Tani, perhaps not unexpectedly, local languages spoken relatively close to the Koro Aka setllements, e.g., certain Western Nishi varieties like Yano and Nyisu, show many parallels with Koro.
Whatever the exact nature of the relationship is, Koro appears to have significant parallels with Proto-Tani and the divergent and important Milang language, which may itself be a sister to the Tani family (Post 2009/2010). Note that it is particularly within the domain of lexical items that Milang possesses but that are not found in other Tani languages that Koro shows the most similarities to, perhaps reflecting a (now assimilated) non-Tani substrate language that is common to both Milang and Koro Aka.
Koro also shows fewer but an overall noteworthy number of correspondences with the Digarish family, with the as yet unclassified Tibeto-Burman languages of western Arunachal Pradesh representing the Kho-Bwa cluster (van Driem 2001): Bugun, Sulung and Sherdukpen, and with the Midzuish family as well. All of these language groups are spoken in Arunachal Pradesh, and a few in adjacent parts of China as well.
A Koro creation myth, as told in Hindi by Katia Yame
It is far from an understatement that much remains to be done on the Koro language. This includes as full as possible descriptions of its lexicon, phonology, and grammar, also to resolve the history and taxonomy of this enigmatic Tibeto-Burman language. Further, we understand very little at present how, in the face of ethnically mixed marriages and submerged or homogenized cultural identities, has the tiny community of this ‘hidden’ language Koro managed to preserve its own identity linguistically. Koro is presently beginning to feel pressure from, and exhibit shift to, Hindi, many young Koro use Hindi exclusively. Thus, we must act now to continue addressing some of the most pressing and urgent tasks before this unique and enigmatic Tibeto-Burman language of Arunachal Pradesh vanishes forever.