Versión en español
The alpaca
RUNNING TITLE: CAMELID EVOLUTION
Jane C. Wheeler
Facultad de Medicina Veterinaria
Universidad Nacional Mayor de San Marcos
Apartado 41-0068
Lima 41, PERU
The alpaca is smaller than the llama and resembles the vicufia in many aspects of morphology and social organization.
Although the Lake Titicaca basin of southern Peru and Bolivia has long been considered the focus of alpaca domestication, archaeological evidence is not presently available to evaluate this hypothesis (Browman, 1989). Nevertheless, excavations in the central Peruvian puna have placed its origins between 7,000 and 6,000 years ago (Wheeler, 1984, 1986), and it was from this region that the alpaca was subsequently moved to lower elevation interandean valleys 3,800 years ago (Wing, 1972; Shimada, 1985).
Evidence of alpaca rearing at coastal sites in southern Peru dates from 900 to 1,000 years ago (Wheeler et al., 1992; Wheeler, in press; Wheeler et al., submitted)(Figure 3D). Precolumbian alpaca remains have not been reported in the faunal materials from archaeological sites in Chile (Dransart, 1991a & b; Hesse, 1982), Argentina (Elkin, personal communication) or Ecuador (Miller & Gill, 1990), although they are found in limited numbers these regions today. It is impossible to estimate the number of preconquest alpacas. Spanish documents record their rapid decimation and displacement to remote, extreme high elevation regions of the Andes (Flores Ochoa, 1977). Recent data indicates that over the last 25 years alpaca numbers have fallen significantly in Peru, from 3,290,000 in 1967 to 2,510,912 in 1986, and in 1991 the total Andean alpaca population was estimated to be 2,811,612 (Wheeler, 1991).
Representatives of two possible preconquest alpaca breeds have been found among the 1,000 year old El Yaral mummies. Fine fiber and extra fine fiber alpacas were distinguished based on physical appearance and average fiber diameter (1,600 fibers measured per animal). The former have fleeces averaging 23.6 (sd ± 1.9 14m), while the latter fleeces average 17.9 (sd ± 1.0 Am)(Wheeler et al., 1992; Wheeler et aL, submitted). Both groups had lustrous fiber ranging from wavy to crimped and dense to very dense. Hairs were visible in 3 of the 4 animals, but were not significantly coarser than the undercoat fibers. Indeed, fiber diameter variation both within and across the fleece was remarkably low, suggesting that rigorous breeding selection for fine quality fiber was being practiced (Figure 6).
The Spanish conquest had a disastrous effect -on both Ilarna and alpaca populations.
Massive mortality accompanied the displacement of alpaca herds from the coast, interandean valleys and most of the puna, as introduced stockrearing practices pushed the survivors into the marginal, extreme high elevation pastures where they are found today (Flores Ochoa, 1982). At present, alpaca distribution extends from approximately 8' S latitude, where they have been recently reintroduced in Cajamarca, to 20' S latitude, in the vicinity of Lake Poopo, Bolivia, with small populations located further to the south in northern Chile and northwestern Argentina.
Today, 75% of all alpacas, paqocha in Quechua (Flores Ochoa, 1988) and allpachu in Aymara (Dransart, 1991b), are held by traditional herders (Novoa, 1989). Two alpaca phenotypes, known in the literature by their Quechua names as suri and huacaya or wakaya, are recognized but these do not breed true. The suri has long straight fibers, organized in waves which fall to each side of the body in much the same manner as a Lincoln sheep, while the huacaya has shorter, crimped fibers which give it a spongy appearance similar to that of a Corriedale sheep. Occasionally animals with intermediate wool characteristics are seen, and these have been named chili by Cardozo (1954). Crosses between huacaya and huacaya produce a certain percentage of suri offspring, and crosses of suri with suri produce some huacaya offspring. Although no artificial selection is made, an estimated 90 percent of all alpacas are huacayas (Novoa, 1989). The suri is not knowamong the Aymara herders of Chile who refer to their huacayas simply as allpachu or alpacas (Dransart, 1991b). The fleece of both phenotypes varies from white to black and brown, passing through all intermediate shades, with a greater tendency to uniform coloration than in the llama. Alpacas with wild vicuiia coloration occur.
In comparison to the preconquest El Yaral alpacas, contemporary Andean huacaya and suri fleeces average 31.2 ± 3.8 itm (Carpio, 1991) and 26.8 ± 6.0 itm (Von Bergen, 1963) respectively, are coarser, may have a tendency to hairiness, and are of uneven quality. Some coats containing up to 40% hair have been reported for both living varieties, and considerable variation is reported in published statistics on fiber diameter. The origin of this degeneration almost certainly lies in the Spanish conquest, but a breakdown in controlled breeding between the fine and extra fine El Yaral breeds would not alone account for the variation observed today.
The most probable cause of coarsening and hairiness in both huacayas and suris would be through hybridization with the coarse fiber llama breed, a not improbable scenario amid the chaos and destruction of the conquest. Clearly, however, such a process would not have affected only the alpaca gene pool. The El Yaral mummies indicate the possibility that extensive crossbreeding between alpacas and llamas may have occurred since the Spanish conquest and has played a much more important role in the formation of today's livestock than has been realized.
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