Southern Pomo switch-reference and its origins within Pomoan

This paper describes the Southern Pomo switch-reference system used in narrative texts. In this genre, switch-reference is shown to be canonical: suffixes applied to dependent verbs indicate whether or not the subject of the dependent verb is shared with a single TAM-bearing main verb. This system is compared with the switch-reference systems (or lack thereof) reported for the other six Pomoan languages. Only Kashaya Pomo is reported to have the same system. The other five Pomoan languages have different systems or none at all. It is asserted that switch-reference was not present in Proto-Pomo and developed in different ways in a subset of daughter languages through entirely internal changes without influence from non-Pomoan language contact. In those languages where switch-reference (whether canonical or not) developed, systems with dedicated bound switch-reference morphemes are hypothesized to have been elaborated around the same two Proto-Pomo suffixes, *-Vn and *-pʰi