agouti

Source

1. A burrowing rodent of the genus Dasyprocta, native to tropical America and usually having brown fur streaked with gray.
2. The alternation of light and dark bands of color in the fur of various animals, producing a grizzled appearance.

[French, from American Spanish agutí, from Guarani acutí.]

(click to enlarge)
Agouti (Dasyprocta). (credit: Warren Garst/Tom Stack & Associates)

Any of several species (genus Dasyprocta) of rabbit-sized rodents that occur in the American tropics (southern Mexico to northern South America). Agoutis are 16 – 24 in. (40 – 60 cm) long and have a long body, small ears, either a vestigial tail or none at all, and slender feet with long, hooflike claws. Their wiry fur is reddish brown to blackish, with individual hairs banded in what is called the agouti pattern. Agoutis generally live in forests and eat roots, leaves, and fruit.

For more information on agouti, visit Britannica.com.

(Dasyproctidae)

Class: Mammalia

Order: Rodentia

Suborder: Hystricognathi

Family: Dasyproctidae

Thumbnail description
Rabbit-sized, large-headed, short-eared, longlegged forest rodent with glossy fur and hind legs conspicuously longer than front legs, giving a "dragster-like" appearance when moving

Size
Dasyprocta: Head and body length, 12.6–25.2 in (32–64 cm); tail, 0.4–2.75 in (1–7 cm); weight, 1.3–8.8 lb (0.6–4 kg); Myoprocta: Head and body length, 12.6–14.9 in (32–38 cm); tail, 1.8–2.75 in (4.5–7 cm); weight, 1.3–2.8 lb (0.6–1.3 kg)

Number of genera, species
2 genera; 13 species

Habitat
Rainforest, secondary forest, scrub, cultivated areas and parks; to 6,560 ft (2,000 m)

Conservation status
Endangered: 2 species; Lower Risk/Near Threatened: 1 species; Vulnerable: 1 species; Data Deficient: 3 species

Distribution
Central and South America

Evolution and systematics

Fossils are known that date from the Oligocene of South America. The family Dasyproctidae belongs to the super-family Caviomorph of the suborder Hystricognathi. Caviomorphs probably evolved in Africa, and (along with cebid primates) crossed a then much-narrower Atlantic to South America in the late Eocene, where they diversified greatly. Many attained great size and occupied a number of ecological roles. Modern caviomorph diversity is but an echo of this. Of the two genera in the Dasyproctidae, the acouchis are considered to be the more primitive; they are smaller, have a longer tail, and exhibit simpler foraging patterns and social structure. The genus Dasyprocta has speciated widely in South America. In addition to the forest species, there are species in the open savanna-like habitat of the cerrado (D. azarae) and scrubby dry caatinga (D. prymnolopha).

Physical characteristics

These are glossy-furred, big-headed, rabbit-sized rodents with chunky bodies on long delicate legs. A prominent nose and whiskers, large eyes, and small ears perch high on the head. The tail is either a tiny nub and barely visible (Dasyprocta) or it is longer and readily visible (Myoprocta). Color is highly variable over the extensive ranges of the two genera; even within species, color variation can also be quite extensive. They are best distinguished from the larger and closely related pacas (Agoutidae) by the absence of prominent patterns of spots and stripes on the flanks. The scientific name is derived from the Greek dasus, meaning "hairy," and proktos, meaning "rump." Agoutis not only have hair on their rumps, but it is especially long hair.

Distribution

Agoutis range from southern Mexico to northern Argentina and Paraguay.

Habitat

Agoutis are associated with primary and secondary forest and scrub. They require some dense vegetation for cover, but often prefer open areas for foraging. Highly adaptable, agoutis are often associated with water, and they frequently display a distinct preference for using stream banks to make burrows.

Behavior

Agoutis are ground living and day active, unless heavily hunted. Their home range will often include several sleeping spots, often inside fallen hollow logs or under tree roots. These spots are so well used that well-beaten paths will radiate out from them into the forest, linking favored foraging and resting sites. A favorite food of jaguar and other large forest carnivores, agoutis and acouchis have many behaviors aimed at predator avoidance. They will freeze in mid-stride if threatened. If threats continue, they will run quickly through the forest, their passage assisted by their cone-shaped body form. When resting, they will sit in an erect body posture with feet and ankles flat on the ground, ready to dart away if danger is sensed. From a standing position, they are able to leap over 6.5 ft (2 m) into the air.

Feeding ecology and diet

Agoutis eat primarily fallen fruit, but their diet also includes insects and shoots. They collect and store seeds and fruit, rarely eating those that have freshly fallen, preferring those in their various scattered and perpetually replenished larders. Some of their stores are forgotten, so agoutis and achouchis are important dispersers of rainforest seeds. Burying the seeds not only reduces insect predation, but also provides the seeds with a better chance of establishing a good root system while germinating, thus reducing vulnerability to the stress of drought. Species such as Hymenaea courbaril originally evolved to be dispersed by large mammals (such as gompotheres) that went extinct in the Pleistocene. Agoutis are now the major disperser and Hymenaea germination rates are very low in areas in which agoutis have been hunted out. Some agouti seed larders are raided by other animals, including peccaries, coatis, and spiny rats. Food is generally eaten while the animal sits on its haunches and holds the food in its hands. This dexterity allows the rodent to manipulate the seed or fruit until the weakest spot is discovered; manipulation then ensures that this area remains under dental attack until the defensive walls are breached. In this way the agouti (and acouchi to a lesser extent) can break open and eat the contents of such hard fruits as the Brazil nut (Bertholecia excelsa).

Reproductive biology

Agoutis are capable of breeding throughout the year, whenever conditions (especially availability of fallen fruit) are favorable. The basic social unit is the mated pair; the pair bond lasts for life. Reproduction may occur twice a year, if food supplies permit. Unlike the familiar rats, mice, and hamsters, these rodents have small litters of large young in which they invest a great deal of time and parental care. The litter size is generally one or two, with occasional records of three and (very rarely) four. Lactation lasts for around 20 weeks. However, because of the high risk of predation, the young are precocial, being born fully furred, with open and functioning eyes and ears. They are well coordinated and able to run within an hour of birth. Gestation varies between 104 and 120 days. The estrous cycle is around 34 days.

Conservation status

The IUCN lists D. ruatanica and D. coibae as Endangered, D. azarae as Vulnerable, D. mexicana as Lower Risk/Near Threatened, and D. cristata, D. kalinowskii, and M. exilis as Data Deficient. The remaining species are not currently threatened.

Significance to humans

Agoutis are often heavily hunted and may constitute a regional mainstay for local hunters. They are a very important disperser of the seeds of rainforest trees.

Species accounts

Resources

Eisenberg, J. F., and K. H. Redford. Mammals of the Neotropics. Vol. 3, The Central Tropics: Ecuador, Peru, Bolivia, Brazil. Chicago: University of Chicago Press, 1999.

Reid, F. A. A Fieldguide to the Mammals of Central America and Southeast Mexico. Oxford: Oxford University Press, 1997.

Asquith, N. M., J. Terborgh, E. Arnold, and C. M. Riveros. "The Fruits the Agouti Ate: Hymenaea courabil Seed Fate When Its Disperser Is Absent." Journal of Tropical Ecology 15: (1999): 229–235.

Dubost, G. "Ecology and Social Life of the Red Acouchy, Myoprocta exilis; Comparison with the Orange–rumped Agouti, Dasyprocta leporina." Journal of Zoology 214 (1988): 107–123.

Lee, T. E. Jr., K. R. Rhodes, J. L. Lyons, and D. K. Brannan. "The Natural History of the Roatán Island Agouti (Dasyprocta ruatanica), A Study of Behavior, Diet and Description of Habitat." The Texas Journal of Science 52:(2000): 159–164.

Forget, P-M. "Scatterhoarding of Astrocaryum paramama by Proechimys in French Guiana: Comparison with Myoprocta exilis." Tropical Ecology 32: (1991): 155–167.

Forget, P-M., and T. Milleron. "Evidence for Secondary Seed Dispersal by Rodents in Panama." Oecologia 87 (1991): 596–599.

[Article by: Adrian A. Barnett, PhD]

A large rodent that resembles the rabbit or hare in size and shape as well as in the elongated hindlegs, which make them well adapted for speed (see illustration). The agouti and the closely related smaller acouchi are inhabitants of clearings in forested areas of the Amazon region. Some range into Central America and as far as the Guianas.

The agouti (Dasyprocta aguti), a rodent found In Mexico, South America, and the West Indies.

Thirteen species of agouti have been described, the most common being Dasyprocta aguti. Some authorities are of the opinion that all of these are varieties or subspecies of D. aguti. The acouchi is represented by two species, the green acouchi (Myoprocta pratti) and the red acouchi (M. acouchy). See also Rodentia.

1. speedy, stout-bodied, nocturnal, South American rodent that bounds like a hare. Called also Dasyprocta aguti.
2. a pattern of pigmentation in which individual hairs have several bands of light and dark pigment with black tips. Seen in hares, Abyssinian cats, guinea pigs, and the agouti, after which it is named.

Agouti refers to a number of species of rodents as well as a number of genes affecting coat coloration in several different animals.

• When referring to a rodent, agouti can mean:
  • The common agoutis (genus Dasyprocta) are those popularly called agoutis.
  • Acouchies (genus Myoprocta), commonly called tailed agoutis.
  • Pacas (genus Cuniculus, which was formerly called Agouti).
  • Agouti is also a domestic variety of guinea pig.

• The agouti gene is one of the genes involved in fur patterns and shadings in animals.
• The agouti signalling peptide is a circulating hormone that acts as an antagonist at melanocortin receptors
• Agouti-related peptide

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