Versión en español
The Vicuna
Jane C. Wheeler
Facultad de Medicina Veterinaria
Universidad Nacional Mayor de San Marcos
Apartado 41-0068
Lima 41, PERU
At present vicuna distribution is limited to areas of extreme elevation between 9' 30' and 29' S latitude in the Andes (Figure 3B). Palaeontological remains suggest, however, that the genus Vicugna may have originated further east on the Argentine plains as early as two million years ago (L6pez Aranguren, 1930; Cabrera, 1932; Webb, 1974; Harrison, 1985), although a recent revisio * ome of these materials has led Menegaz et al. (1989) to conclude that the vicuiia evolved from the guanaco at the beginning of the Holocene. None the less, mtDNA sequence data support a divergence of at least two million years between vicufta and guanaco (Stanley et. al, 1994), and fossils from Tarija, Bolivia include vicuna remains (Hoffstetter, 1986) dated to between 97 and 73,000 years ago (MacFadden et al., 1983) indicating that their range had expanded westward to the Andes by that date. However, it was only with the Pleistocene glacial retreat and
establishment of the present Holocene climatic regime between 12-9,000 BP that Vicugna moved into their present high elevation puna habitat (Hoffstetter, 1986; Wheeler, Pires-Ferreira & Kaulicke, 1976). Vicufla remains have not been found in either palaeontological deposits (Hoffstetter, 1986) or archaeological sites (Miller & Gill, 1990) in Ecuador and Columbia.
In 1957, however, Koford calculated the total Andean vicuña population to be at most 400,000, including 250,000 in Peru. By 1969, Grimwood reported only 10,000 in Peru, and two years later Jungius (1971) estimated a total of between 5,000 and 10,000 in Peru with another 2,000 living in Bolivia, Argentina and Chile.
The present Andean population probably exceeds 93,000 thanks to rigorous protection programs in the area (Wheeler, 1991).
Two subspecies of vicufla have been described. The first, Vicuzna vicuizna viculyna (Molina, 1782) is said to occur between 18' and 29' S latitude, while the second, V.v. mensalis (Thomas, 1917) is reported between 9' 30' and 180 S latitude.
Separation of V.v. mensalis was based on its smaller size relative to V.v. vicugna, 45 versus 57 mm for length of the molars and 70 versus 90 cm for withers height (Thomas, 1917), however a recent study of 50 male and 50 female V.v. mensalis (1.5 to 6.5 years old) from Pampa Galeras, Peru, reports average withers height measurements of 86.5 cm for females and 90.4 cm for the males (Paucar et al., 1984).
No clearly defined geographic separation exists between the two proposed vicuna subspecies and many authors ignore V.v. mensalis (Osgood, 1943; Gilmore, 1950; Dennler de la Tour, 1954b; Grimwood, 1969; Koford, 1957). Osteological remains from Andean archaeological sites point to the origin of alpaca domestication from vicuna at high elevation localities within the range of V.v. mensalis approximately 6,000 years ago (Wheeler, 1984, 1986, 1991; Moore, 1988, 1989). A third purported subspecies, V.v. elfridae Krumbiegel, 1944 has been described based on specimens found in German zoos.
Recent survey data compiled by Torres (1992) shows vicuna populations spread throughout the high Andean puna ecosystem (at 3,800 meters above sea level and higher) from 9' 30' to 29' S latitude, without any obvious geographic clustering which might suggest two distinct subspecies (Cajal, 1992; Glade, 1992; Hoces, 1992; Villalba, 1992). None the less, sufficient phenotypic differences appear to exist between the northern (Peruvian, Chilean, Bolivian) and southern (Argentine) vicufia populations to justify the existence of at least two geographic races.
The best studied vicuiia, the northern V.v. mensalis, is distinguished primarily by the long growth of hair on the chest. The head, neck, back, sides and dorsal surface of the tail are a dark cinnamon color, with white covering the lower portion of the face, the chest, belly, interior surface of the legs and ventral surface of the tail. The eyes and edges of the ears are outlined in white. Average coat length is 3.28 cm in adult animals and the long chest hairs reach 18 to 20 cm (Hofinann et aL, 1983). Fleece fiber diameter is 12.52 ± 1.52 Am (Carpio & Solari, 1982a) and the average fleece fiber length is 3.2 cm in adult males (Carpio & Santana, 1982). Follicle density averages 78.65 per MM2 (Carpio & Solari, 1982b) and the frequency of primary hair in the fleece is 2% (Carpio & Solari, 1982a).
In contrast, V.v. vicugna lacks the long chest hairs, and has a lighter beige pelage coloration with white covering a greater portion of the body, rising halfway up the sides to mid-rib height and all the way to the ilium crest, as well as covering the anterior portion of the rear legs.
Total length measurements from the Paucar study of V.v. mensalis from Pampa Galeras (Paucar et al., 1984) are 96.3 cm for females and 110.7 cm for males, with average weights of 33.2 kg and 36.2 kg respectively. These figures contrast with the total length measurements of 137-181 cm reported by Hofmann et aL (1983) for 19 adult vicuiias from the same local. Gilmore (1950) and Pearson (1951) also report greater total lengths, 144 to 175 cm, and heavier live
weights, 45-55 kg for V.v. mensalis. We have not encountered similar comparative statistics for V.v. viculyna.
In contrast with the continuing decline of guanaco numbers, the vicufia has made a remarkable recovery over the last 20 years, passing from endangered status in 1969, to vulnerable in 1972 (Thornback & Jenkins, 1982). This change is a direct result of conservation programs. In 1957, Koford estimated the total Andean vicufla population to be 400,000 at the most, including 250,000 in Peru. In 1969, Grimwood reported only 10,000 in Peru, and two years later Jungius (1971) calculated a total of between 5,000 and 10,000 in Peru with another 2,000 living in Bolivia, Argentina and Chile. In 1982, 15 years after the establishment of a protection program, the Peruvian population had risen to 62,000 (Franklin, 1982), and in 1991, the total Andean population reached 92,882 (Wheeler, 1991).
In Peru, conservation efforts at the Pampa Galeras reserve began in 1968 with 1,753 vicuiias. During the first years, an unexpected annual population increase of 21 % was registered at Pampa Galeras (Sdnchez, 1984). This high growth rate has subsequently been repeated when Chilean and Bolivian reserves were established (Rodriguez & Torres, 1981; Rabinovitch, Hernandez & Cajal, 1985). In 1978-79 however, the Pampa Galeras population reached a crisis brought on by prolonged drought, overgrazing and over population, and a negative 11.28% growth rate was registered. During this period pregnancy rates decreased from 85% to 58% and recruitment dropped from 76% to 27% (Otte & Hoftnann, 1981). Abortion rates rose dramatically and pregnancy was delayed from once a year to once every two years (M6nard, 1982) while adult mortality increased from 5.6% to 27.6% (Sdnchez, 1984). The present situation appears to have improved remarkably, but exact census data are lacking due to recent security problems in the area.
ORIGIN OF THE DOMESTIC FORMS
To date the earliest evidence of camelid domestication comes from archaeological sites located between 4,000 and 4,900 meters elevation, in the puna ecosystem of the Peruvian Andes. Both guanaco (L.g. acsilensis) and vicuna (V.v. mmensalis) have inhabited this tundra environment for approximately 12,000 years and, together with the huemul deer Hij2j2ocamelus antisensis (d'Orbigny, 1834), were the primary prey of early human hunters. Faunal materials from archaeological sites (Wing, 1986; Wheeler, 1984, 1986; Wheeler et aL, 1976; Moore, 1988, 1989) indicate that during the earliest occupation of this zone, 12,000 to 7,500 years ago, approximately equal numbers of camelids and deer were hunted, while during later periods the frequency of camelid remains increased dramatically suggesting a shift to the utilization of domestic animals. Archaeozoological data from one of these sites, Telarmachay Rockshelter, have produced the most extensive evidence concerning this shift to date (Wheeler, 1984, 1986).
Located 170 km north-east of Lima, Peru (I I' I I' S latitude and 75 ' 52' W longitude), at 4,420 meters above sea level, Telarmachay is situated near the absolute upper limits of crop growth potential. Mean annual temperature is 4.8' C, with an average daily variation of greater than 20' and frost occurs 330 nights of the year. Annual precipitation averages 500 to 1,000 mm and is normally restricted to the months from November to March, although the timing is irregular and unpredictable, and extended periods of drought occur. No agriculture is practised in the area today, and grazing ungulates represent the most reliable food resource. This is due to their mobility during periods of drought and their ability to convert the dry ligneous puna grasses into a source of stored protein which can be utilized for human consumption. Palaeoclimatological data indicate that no significant climatic changes have taken place in this area over the last 10,000 years (Van der Hammen & Noldus, 1986).
Five seasons of excavation at Telarmachay Rockshelter (Lavallee et al., 1986) revealed a 8,200 year long occupational sequence and recovered more than one metric ton of animal bones from the preceramic levels. Archaeozoological analysis of these materials produced evidence of a shift from generalized hunting of guanaco, vicuna and huemul deer 9,000-7,200 years ago, to specialized hunting of guanaco and vicufia approximately 7,200-6,000 years ago, then to control of early domestic alpacas and llamas by 6,000-5,500 years ago, and finally, to the establishment of a predominately herding economy beginning 5,500 years ago (Wheeler, 1986, unpublished data).
It has not been possible to determine if these shifts were associated with body size reduction as has been documented for other domestic ungulates because species specific characters for separating postcranial bones are lacking. Instead, determination of early camelid domestication at Telarmachay is based upon an increase in the frequency of both camelid and neonatal camelid remains, together with changes in dental morphology. During the preceramic period, 9,000 to 1,800 years ago, camelid remains gradually increased from 64.7% to 88.6% of the faunal assemblage, while deer remains diminished from 34.2% to 9.2% of the total (Wheeler, 1986). This shift was not caused by decreased availability of deer in the zone, but rather, by a change in animal utilization patterns from generalized to specialized hunting and eventual domestication of the camelids.
Between 9,000 and 6,000 years ago, camelid remains increased from 64.7% to 81.7% of the total faunal sample, with just over one third (35.3 % to 37. 1 %) of the bones coming from fetal or neonatal animals (Wheeler, 1986). These figures are consistent with a hunting economy because between 35% and 40% of animals in contemporary guanaco and vicufia populations fall within this category (Franklin, 1978, personal communication). Thus, the ever greater dependence upon camelids in the diet during this period suggests increasing specialization in guanaco and vicuna hunting.
Around 6,000 years ago, however, the frequency of foetal and neonatal camelids increased markedly to 56.8%, and continued to rise until it reached 73.0% of all camelid remains in the deposits dated to 3,800 years ago (Wheeler, 1986). These figures suggest either the development of specialized hunting of neonates, an economically unviable strategy, or the appearance of other mortality inducing factors in the environment. They far exceed expected frequencies for both the foetal/neonatal age group and the natural (i.e. no human hunting) mortality rates of 4.5 (Raedeke 1979:199) to 30% (Franklin, 1978:42) which have been recorded for the guanaco and vicufia, but closely correspond with mortality rates experienced by llama and alpaca breeders today.
At present, up to 70% of each year's young may be lost before two months of age due, in part, to failure of passive immune transfer (Garmendia et aL, 1987) with resulting mortality from Clostridium perfringens Type A enterotoxaemia and other pathogens (Legufa, 1991; Ramfrez, 1991). The epizootic nature of enterotoxaemia is to some extent controlled by climatic conditions that permit sporulation of the bacteria, as well as by the presence of a critical number of captive or domestic animals. In the Andes, outbreaks of enterotoxaemia are associated with unsanitary corralling practices during the wet season birth period. Similar epidemics are not known to occur in the wild camelids.
Although it is not always possible to distinguish between the bones of a terminal eleven and one half month foetal camelid and those of a neonate, tooth wear studies indicate that the majority of Telarmachay specimens dating from 6,000 to 3,800 years ago were neonatal, whereas those from the earlier levels were primarily foetal, presumably taken in utero through the hunting of pregnant females (Wheeler, 1986). This shift from predominantly foetal to neonatal remains coincides with the significant increase in frequency of foetal/neonatal remains described above, and permits the hypothesis that mortality induced by disease rather than by intentional butchery was the cause.
Additional support for this interpretation comes from the study of bone distribution across
the 6,000 to 3,800 year old living floors which indicates that newborn camelids were brought into the shelter whole and processed for consumption. The resultant pattern is very similar to that created by contemporary traditional herders who utilize dead llama and alpaca neonates for food. Meat produced by the often massive die-off of camelid neonates does not now, and apparently did not then, go to waste.
Identification of the species which was brought under domestication at Telarmachay is based upon incisor morphology. Prior to domestication (9,000 to 6,000 BP) it is estimated that nine vicufias were hunted for every guanaco based on incisor type and frequency. Vicuflas have rootless hypselodont parallel-sided permanent incisors with enamel covering the entire labial surface, and root-forming deciduous incisors with enamel covering the upper labial surface only (Miller, 1924; Wheeler, 1982, 1991). Guanacos have rooted deciduous and permanent spatulate incisors with an enamel covered crown (Miller, 1924). By 6000 BP, however, the remains of permanent incisors with the same morphology as deciduous vicuna incisors appear in the Telarmachay deposits (Wheeler, 1982, 1991,unpublished data). These permanent teeth match the dentition of many extant Peruvian alpacas in which both the deciduous and permanent incisors are root forming and parallel sided, with enamel covering only the upper labial surface (Wheeler 1991, unpublished data). Although contemporary alpacas with spatulate llama incisors have been reported by Kent (1982), it is unclear if these are hybrids. The evidence from Telarmachay suggests an ancestral relationship which may explain the apparent retention of juvenile vicufia dental traits in the adult alpaca. It cannot be determined if animals with llama type incisors also appeared in the 6000 BP deposits, since these are indistinguishable from guanaco incisors, but the presence of both large and small neonates suggests that this may have been the case.
In contrast to the data from Telarmachay and other Andean archaeological sites which
indicates that the llama is descended from the guanaco and the alpaca from the vicufia (Figure 5A),
other researchers have come to different conclusions about their ancestry based on the study of living animals. In 1775, Frisch attributed the origin of the llama to the guanaco and the alpaca to the vicuna, an opinion subsequently supported by Ledger (1860), Darwin (1868), Antonius (1922), Faige (1929), Krumbiegel (1944, 1952), Steinbacher (1953), Frechkop (1955), Capurro and Silva (1960), Akimushkin (1971) and Semorile, Crisci and Vidal-Rioja (in press). Other authors have concluded that both domestic camelids descend from the guanaco, and the vicufia was never domesticated (Figure 5B)(Thomas, 1891; Peterson, 1904; Hilzheimer, 1913; L6nnberg, 1913; Brehm, 1916; Cook, 1925; Weber, 1928; Herre, 1952, 1953, 1976, 1982; R6hrs, 1957; Fallet, 1961; Zeuner, 1963; Herre & Thiede, 1965; Herre & R6hrs, 1973; Bates, 1975; Pires-Ferreira, 1981/82; Kleinschmidt et aL, 1986; Kruska, 1982; Jilrgens et al., 1988; and Piccinini et al., 1990). In the 1930's, L,6pez Aranguren (1930) and Cabrera (1932) suggested that llama and alpaca evolved from presently extinct wild precursors, based on the discovery of 2 Myr PlioPleistocene L. glama, L. pacos, L. Lyuanicoe and V. vicu-una fossils in Argentina, and that the guanaco and vicufia were never domesticated. This position is no longer considered a possible alternative. Finally, Hemmer (1975, 1983, 1990) attributes llama ancestry to the guanaco, but has deduced on the basis of shared morphological and behavioral traits that the alpaca originated from hybridization between the llama and vicufia (Figure 5C).
Conclusions about llama and alpaca ancestry have, in large part, been based upon morphological changes produced by the domestication process. During the 1950's, Herre and R6hrs (Herre, 1952, 1953, 1976; Herre & R6hrs, 1973; Rbhrs, 1957) examined alterations in the mesotympanal area of the skull related to a decrease in llama and alpaca hearing acuity, and reported an overall reduction in cranial capacity of both domestic species relative to the guanaco. In contrast, they found the vicuiia cranium to be the smallest of all living Lamini, and, based on the premise that domestic animals are smaller than their ancestors, concluded that this species was never brought under human control.
Herre and R6hrs consider the llama and alpaca to be "races
of the same domestic species bred for different purposes." (Herre, 1976:26). Research on the relationship of brain size relative to body size by Kruska (1982) also found the vicufia to be smaller than alpaca and llama, which in turn were smaller than the guanaco suggesting that the latter is the only ancestral form. None the less, papers by Jerison (1971) and Hemmer (1990) report the ratio of alpaca brain size to body size to be smaller than in the vicuiia permitting a different conclusion about origins of the domestic forms. These contradictory data on size reduction are almost certainly a product of sampling as neither subspecific variation in the wild forms nor the possibility of hybridization between the domestic animals were considered in any of the studies.
Based on the study of pelage characteristics (skin thickness, follicle structure,
secondary/primary ratio, fiber length and diameter, coloration) in living camelids, Fallet (1961) found the llama to be an intermediate evolutionary stage between the wild guanaco and the specialized fiber producing alpaca; and concluded that the absence of transitional characteristics between vicuiia and alpaca fleeces eliminates the former from consideration as an ancestral form. This deduction is, in part, based on the assumption that llamas have been selected exclusively for use as pack animals while alpacas have been bred for fiber production. None the less, new data on preconquest llama and alpaca breeds in Peru have revealed the prior existence of a fine fiber producing llama, as well as an extra fine fiber alpaca which is transitional between the vicuiia and a second prehispanic fine fiber alpaca breed (Wheeler, Russel & Stanley, 1992; Wheeler, Russel & Redden, submitted).
Research on camelid behaviour has produced contradictory hypotheses concerning llama and alpaca origins. Krumbiegel (1944, 1952) and Steinbacher (1953) argue that the alpaca is the domestic vicuna based on unique shared behavioural traits which are said to differ from those observed in the guanaco and llama. Hemmer, on the other hand, concludes that while some
alpaca behaviour patterns match those of the vicufla, others are intermediate between those of vicuiia and guanaco, suggesting that "the alpaca is a mixture of both lines, [produced] by crossbreeding of captured vicunas with the only initially available domestic animal, the llama" (1990:63). It has also been suggested that the vicuiia was never domesticated because it is more territorial than the guanaco (Franklin, 1974). None the less, this assumption is open to question because it is based upon study of guanacos located at the southerm-nost extreme of their range where seasonal migration in response to severe climatic changes is essential for survival (Franklin, 1982, 1983).
Further to the north, where vicufia and guanaco ranges overlap and llama and alpaca domestication occurred (Wheeler, 1984), a more benign climate and a constant food supply permit the characteristic sedentary social organization of the vicufia (Franklin, 1982, 1983). Although data concerning behaviour of the guanaco in this region are lacking, it is possible that the limited sedentary territorial organization observed in some Patagonian groups plays a more important role in these less extreme climatic conditions.
Analysis of hemoglobin amino acid sequences in vicufia, alpaca, llama and guanaco from Hannover Zoo, Germany, led Kleinschmidt et al. ( 1986), Jiirgens et al. (1988), and Piccinini et aL (1990) to the conclusion that the vicufia was never domesticated. However, earlier research on blood and muscle samples from llama, alpaca, vicufia, guanaco and alpaca x vicufia hybrids at Santiago Zoo (Cappuro & Silva, 1960) indicated a llama-guanaco and alpaca-vicufia subdivision, as have more recent data from ribosomal genes (Semorile et al., in press). Other researchers utilizing immunological, electrophoretic analysis and protein sequencing have found it impossible to draw conclusions about llama and alpaca ancestry (Miller, Hollander & Franklin, 1985; Penedo et al., 1988).
Cytogenetic studies (Capanna & Civitelli, 1965; Taylor et al., 1968; Larramendy et aL, 1984; Gentz & Yates, 1986) indicate that all four species of the South American Camelidae have the same 2n = 74 karyotype, but information on molecular biology is limited. Vidal Rioja et aL (1987) and Saluda-Gorgul, Jaworski and Greger (1990) have examined satellite DNA, and
research analyzing the full mitochondrial cytochrome b gene sequence in all six Camelidae has documented hybridization among the domestic South American camelids (Stanley et aL, 1994). Recent studies of the fiber from mummified ninth and tenth century llamas and alpacas suggests that post-conquest hybridization has modified the genetic makeup of living populations (Wheeler et aL, 1992), a fact which may well explain the diversity of conclusions about their ancestry.
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