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The first SACs migrated to South America at the beginning of the Pleistocene epoch (approximately three million years ago) when an open land connection between North and South America developed [8, 29]. The Isthmus of Panama was formed by volcanic eruptions from the ocean floor, forming a series of islands that ultimately became interconnected (the Caribbean land bridge). The major earliest SAC genus appearing in South America was Hemiauchenia (Tanupoloma), which radiated throughout the flatter regions east of the Andes. During the middle Pleistocene, the genera Palaeolama, Lama, and Vicugna developed from the long‐limbed, flatland‐adapted Hemiauchenia. These genera had shorter limbs, which more easily adapted them to the mountainous Andes.

Various species of Palaeolama migrated back to North America. Fossils associated with North American Hemiauchenia have been found along the Gulf Coast and Florida (Figure 1.16) [30].

Table 1.2 Characteristics of South American camelids.

Characteristic	Vicuña	Alpaca	Guanaco	Llama
Types/breeds/subspecies/races	Peruvian – Apron or bib on frontal chest	Huacaya – Fibers with light crimp. Fleece at right angles to body.	May be as many as four subspecies or races	South American breeds: Heavy neck fiber (chaku, lanuda, tapada)
	Argentine – No chest bib	Suri – Fiber lacks crimp. Fleece hangs in ringlets.		Short neck fiber (ccara, pelada). No North American breed standards. Alpaca and Llama Show Association show classification: Light, medium, and heavy wool divisions.
Conformation
Topline	Straight with rounded rump	Straight with rounded rump	Straight or slightly rounded from withers to tail	Straight from withers to tail
Head and neck carriage
Alert	Vertical	Vertical	Vertical	Vertical
Resting	Vertical	15° from vertical	Vertical	Vertical
Ears	Short, curved on both borders	Short, spear‐shaped, curved on both borders. Huacaya – sharp tip. Suri – rounded tip.	Medium length, curved on both borders	Long, inner border straight or curved inward (banana ears)
Face	Short	Short	Medium	Long
Pastern	Sloped	Almost vertical	Sloped	Sloped
Fiber
Diameter in microns (avg.)	10–30 (13–14)	Huacaya – 16–40 (22) Suri – 16–35 (23)	18–24	Undercoat – 16–40 (26) Guard hair – 40–150 (70)
Quality	Finest of all SACs. Staple short.	Excellent. Staple long.	Inner coat is excellent; juvenile pelts are used for fur garments. Staple short.	Variable; inner coat may make excellent garments. Staple may be long or short.
Coverage	Uniform over body, head, and upper legs. No topknot.	Topknot present. Fiber extends below the knee and hock.	No topknot. Uniform over body, head, and upper legs.	Fiber usually doesn't extend much below the knee or hock or onto the face.
Guard hair	The bib and lower body fiber are guard hairs.	Highest‐quality animals have no guard hair.	Concentrated on lower parts of body and limbs.	Numerous.
Color	Color pattern similar to that of guanaco, but the basic body color is a yellowish light brown. The white in front of the rear limbs may extend to the top of the back. Argentine subspecies has long white guard hairs on the chest, but this is extended into a bib (8–14 in./20–35 cm) in Peruvian subspecies.	22 solid colors recognized, ranging from white to black. Multicolored fleeces also produced.	Basic body color light to dark reddish brown (cinnamon) above, whitish hair below (countershading). White extends up behind the foreleg and in front of the rear leg, around the perineum, inside of legs, and up the bottom of the neck. Front and outside of the upper limbs are body color or gray. Head, face, and ears are dark gray to black, with the darkest color over top of the head and bridge of the nose.	Numerous solid colors from white to black. Multicolors (pinto, appaloosa) also seen.
Teeth	Incisors long, narrow (sides parallel) and continue to grow throughout life. Enamel present only on labial side of the incisor teeth.	Incisors elongated and continue to grow into adulthood. Enamel present only on labial side of incisors.	Incisors broad, spatulate‐shaped and do not continue to grow. Enamel surrounds the crown of the incisors.	Incisors like those of guanaco.
Feeding strategy	Grazer/browser.	Prefers to graze succulent forage in marshes and moist places but also utilizes drier grasses and shrubs.	Uses broad range of habitat for grazing and browsing.	Browser by preference but grazes grasses, even dry, harsh species.

Table 1.3 Weights and sizes of South American camelids.

Characteristic	Vicuña	Alpaca	Guanaco	Llama
Weight (lb/kg)
Adult	99–121/45–55	121–200/55–90	220–265/100–120	250–550/113–250
Birth	9–13/4–6	13–20/6–9	18–33/8–15	18–40/8–18
Height (in/cm)
Adult, at withers	34–38/86–96	30–38/76–96	43–45/110–115	40–47/102–119
Some imports 38 in.

Table 1.4 Characteristics of camels.

Characteristic	Dromedary Camelus dromedarius	Bactrian Camelus bactrianus	Wild Bactrian C. bactrianus ferus
Breeds/types	50 different breeds recognized	Geographical differences	Single type
	Draft type: heavy body, stocky legs
	Riding type: Slim body, long legs
	Racing type: Similar to riding
Weight (kg)	300–650a	450–700	450–690
Weight of newborn (kg)	26–45	35–54	?
Height at shoulder (cm)	180–210	180–195	180–200
Body length (cm)	120–200	120–200	140–156
Shape	1 firm, upright hump	2 large humps, may be flopped over	2 small, conical humps
Color	Cream to tan to dark brown	Cream to tan to dark brown	Cream to gray–brown
Unique anatomy	Male has a soft palate diverticulum (dulaa) which may protrude from mouth	No dulaa, ears 15 cm	No dulaa, prominent toenail, small foot and flat sole for rapid gait to escape predation. Able to drink salty water, face narrow, ears 10 cm
Fiber/hair	Diameter 20–50 μ	Diameter 10–40 μ, long staple, primary source for camel hair garments.	Short fiber
Special adaptations		Adapted to cooler, arid environments.	Adapted to the deserts of northern China and Mongolia.
Running speed (kph)	21.6–40.3	15–20	40

^a Males, castrated as juveniles, may grow taller and larger than 1134 kg (2500 lb).