In this study, the Comparative Method is applied to materials from five extant Costa Rican languages--Guatuso, Cabecar, Bribri, Terraba and Boruca--collected by the author, and to those of Muisca, an extinct Colombian language, collected in the XVII century by missionaries.
Descriptions of the phonemic systems of the six languages, a prerequisite for the comparative work, are included.
The comparison yielded the following inventory of proto-phonemes: /*i *I *e * *a *u *U *o *p *t *k *? *b *d *g *s *h *r*r *l/; nasalization, /* /; stress /* /, and two tones, /* / (high)and / / (low). In addition, two sequences of consonants - /*pk/and /*ts/ - were reconstructed. These, due to their uniquenessand their distributional characteristics could, perhaps, be treatedas units.
Additional data are given from thirteen other languages (Paya, Rama, Cuna, Dorasque, Move, Bocota, Tunebo, Cagaba, Guamaca, Bintucua, Atanques, Chimila and Dobocubi) showing the reflexes that could be established of the segmental proto-phonemes and /* /.
The six languages on which the reconstruction is based are classified according to shared innovations, and their relationships are represented in a family tree scheme according to which the main division in the family is between a Talamancan branch, which includes Bribri, Cabecar and Terraba, and a branch of B-P merging languages, which includes Guatuso, Boruca and Muisca (and also the thirteen languages that were secondarily added to the comparison).
The evidence provided by this study shows that from the point of view of the phonologic developments, diversity is greater to the north (Honduras, Nicaragua, and Costa Rica) and uniformity to the south (Panama and Colombia). This supports the hypotheses that propose an original Middle American homeland for the Chibchan peoples.
The cognate sets are listed at the end of the study, arranged in alphabetical order according to their English glosses. Etymological commentaries accompany them whenever they seem necessary.
