Revista Chilena de Historia Natural 80 (2): 121-140, 2007
RESEARCH ARTICLE
Systematics, taxonomy and domestication of alpaca and llama: new chromosomal and
molecular evidence
Four camelid species exist in South America: two wild, the guanaco (Lama
guanicoe) and the vicuña (Vicugna vicugna), and two domestic, the alpaca (Lama pacos) and the
llama (Lama glama). However, the origin of the domestic species has been a matter of debate. In the present
study, variations in chromosome G banding patterns and in two mitochondrial gene sequences have been used to study
the origin and classification of the llama and alpaca. Similar patterns in chromosome G band structure were observed in
all four Lamini species, and these in turn were similar to the bands described for camels, Camelus
bactrianus. However, fine and consistent differences were found in the short arms of chromosome 1, separating
camels, guanacos and llamas from vicuñas and alpacas. This pattern was consistent even in a hybrid guanaco x alpaca.
Equivalent relationship showed the complete cytochrome b gene sequences, and the minimum expansion tree of the
partial control region sequence, grouping guanaco with llama and vicuña with alpaca. Phylogenetic analyses
showed V. vicugna and L. guanicoe as monophyletic groups. Analysis of both gene sequences revealed two
clades within vicuña, concordant with the two described subspecies, but the results for guanaco did not confirm existence
of the four previously proposed subspecies. The combined analysis of chromosomal and molecular variation showed
close genetic similarity between alpacas and vicuñas, as well as between llamas and guanacos. Although
directional hybridization was revealed, our results strongly support the hypothesis that the llama would have derived
from L. guanicoe and the alpaca from V. vicugna, supporting reclassification as V.
pacos.
Key words:
Camelidae,
Lama pacos, Vicugna pacos, Lama glama, chromosome, cytochrome b, d-
loop
