The llama (Lama glama) is a domesticated descendent of the guanaco (L. guanaco) (Nowak, 1991). Evidence for domestication dates back between 6000 and 7000 years ago and has been found from archaeological sites in the Andean mountains at elevations ranging from 4000 m to 4900 m (Wheeler, 1995). The species is currently distributed from Peru to northwest Argentina (Nowak, 1991).
The llama belongs to the group Camelidae, which includes all species of South American and Old World camelids. Altogether, there are three genera within camelidae, Lama and Vicugna in South America and Camelus in the Old World (Wheeler, 1995). |
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Camelidae has several distinguishing characteristics. Camelids lack horns or antlers (Wheeler, 1995) and have a long, thin neck (Nowak, 1991). The stomach is divided into three sections and is ruminating. In the hindlimb, camelids have a highly reduced fibula. The foot bones are fused into a single bone known as a cannon bone and the feet are made up of only two digits (Nowak, 1991). Instead of having a hoof, camelids have a nail that covers the digits. Finally, individuals are able to rest on their stomach by bending their hindlimbs beneath their body (Wheeler, 1995).
Camelids are diurnal and wild individuals typically inhabit semi-arid plains, deserts and grasslands (Nowak, 1991). They are characterized as grazers and feed mostly on grasses. Camelids are infamous for spitting their stomach contents when irritated (Nowak, 1991).
The llama ranges from 1.2 m to 2.2 m in length with a tail length of 15 cm to 25 cm. Height at the shoulder ranges from 0.9 m to 1.3 m. Llamas typically weigh between 130 kg and 155 kg. Llama wool is dense although very fine. Generally, llamas are brown or black, although some individuals are white with dark spots. Llamas are very strong animals and can travel long distances at high elevations. Llamas have the ability to carry loads up to 96 kg for 26 km per day at elevations up to 5000 meters (Nowak, 1991)!
Additional Information on the Skull
Click on the thumbnails below for labeled images of the skull in standard anatomical views.
Literature
Fowler, M. E. 1984. Clinical anatomy of the head and neck of the llama, Lama glama; pp. 141-149 in O. A. Ryder and M. L. Byrd (eds.), One Medicine: A Tribute to Kurt Kenirschke. Springer-Verlag, Berlin.
Geisler, J. H. 2001. New morphological evidence for the phylogeny of Artiodactyla, Cetacea, and Mesonychidae. American Museum Novitates 3344:1-53.
Jerison, H. J. 1971. Quantitative analysis of the evolution of the camelid brain. American Naturalist 105:227-239.
Owen, R. 1870. On remains of a large extinct lama (Palauchenia magna, Ow.) from Quaternary deposits in the Valley of Mexico. Philosophical Transactions of the Royal Society of London 160:65-77.
Nowak, R. M. 1999. Walker's Mammals of the World, Vol. II. Johns Hopkins University Press, Baltimore, Maryland.
Wheeler, J. C. 1995. Evolution and present situation of the South American Camelidae. Biologica Journal of the Linnean Society 54:271-295.
Links
Lama glama on the Animal Diversity Web (Univ. of Michigan Museum of Zoology).
Images and animations of the brain of the llama on Comparative Mammalian Brain Collections (Univ. of Wisconsin, Michigan State, and National Museum of Health and Medicine).
Photographs of Lama glama on CalPhotos (Berkeley Digital Library Project).
More information about Lama glama on ultimateungulate.com
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