Brown-throated three-toed sloths are native to South America and southern Central America. Their geographic range includes Bolivia, Brazil, Columbia, Ecuador, Honduras, Nicaragua, Panama, Paraguay, Peru, and Venezuela. Although once present in Argentina, it is now thought to be extinct. (Chiarello, 2008)
Brown-throated three-toed sloths can be found in many new-world tropical forests, though some have also been discovered in semi-deciduous forests and subtropical lowlands and swamps. They live in the canopy for the majority of their lives and are capable swimmers. They seldom travel on the ground. They can be found at elevations ranging from sea level to 2400 m. Although not selective about the species of tree they choose to inhabit, they tend to seek out trees with crowns that are highly exposed to sunlight. This preference has been attributed to the sloths using sunlight to fulfill their thermoregulatory needs. ("Brown-throated three-toed sloth (Bradypus variegatus)", 2008; Chiarello, 2008)
- Aquatic Biomes
- rivers and streams
- Other Habitat Features
- Range elevation
- 0 to 2400 m
- 0.00 to 7874.02 ft
As indicated by their common, brown-throated three-toed sloths have brown coloration on their throat and head. Their coat consists of a layer of short, soft, and fine fur and a layer of thick, woolly fur. Algae often resides on outer layer, giving some individuals a greenish appearance. They have long forelimbs with three clawed-toes on each limb. They also have approximately 10 cervical vertebrate that enable them to rotate their necks up to 270 degrees. Their teeth are cylindrical and lack enamel. Similar to many ungulates, their stomachs are multi-compartmentalized, with intestinal microfauna that help digest cellulose from their exclusively vegetarian diets. Even as endotherms, brown-throated three-toed sloths have difficulty regulating their body temperature in cold environments and in cooler ambient temperatures. This is likely due to sparse muscle mass, their relatively small heart, and low-ranging heart rate. Adults range in mass from 3.49 to 5.19 kg, with an average of 4.34 kg. Average length is 60 cm, and they have a basal metabolic rate of 147 cm^3 oxygen/hour. Although size-dimorphism is not present in this species, males have a mid-dorsal speculum that is not present in females. (Feldhamer, et al., 2007; Gilmore, et al., 2001; Gilmore, et al., 2000)
- Sexual Dimorphism
- sexes colored or patterned differently
- Range mass
- 3.49 to 5.19 kg
- 7.69 to 11.43 lb
- Average length
- 60 cm
- 23.62 in
- Average basal metabolic rate
- 147 cm3.O2/g/hr
Brown-throated three-toed sloths are thought to be monogamous. Females vocalize to attract males when they are ready to mate. Females typically mate with the first male they encounter. Although it is unclear if they have a defined breeding season, evidence suggests mating occurs just prior to the rainy season. Copulation lasts 10 to 15 minutes and takes place in the female's tree, approximately 15 m above the ground. During copulation, the male positions himself behind the female. Once mating is complete, the male leaves shortly there after. (Bezerra, et al., 2007)
- Mating System
- Key Reproductive Features
- year-round breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- Breeding interval
- Brown-throated three-toed sloths breed once yearly
- Average number of offspring
- Range gestation period
- 5 to 8 months
- Average weaning age
- 4 months
- Range time to independence
- 2 to 4 months
- Average age at sexual or reproductive maturity (female)
- 3 years
- Range age at sexual or reproductive maturity (male)
- 3 to 5 years
Brown-throated three-toed sloths give birth on the ground or in trees. During birth, the mother pulls the infant between her hindlegs, and other sloths aid in the birthing process by cleaning the mother and infant and by ensuring that the infant doesn't fall. Mothers help young establish motor behavior, posture, learning development, and independent exploration in young. Paternal care is thought to be non-existent in this species. (Gilmore, et al., 2000)
- Parental Investment
- female parental care
In the wild, the lifespan of adult brown-throated three-toed sloths is typically between 30 and 40 years. There is no other information available regarding the lifespan of this species. (MORAES-BARROS, et al., 2011; MORAES-BARROS, et al., 2011; MORAES-BARROS, et al., 2011)
- Range lifespan
- 30 to 40 years
- Range lifespan
- Typical lifespan
- 30 to 40 years
- Typical lifespan
Brown-throated three-toed sloths sleep approximately 14 to 16 hours a day and are both diurnal and nocturnal. They are active for approximately 8 to 10 hours a day, which is typically partitioned into discrete 2 to 3 hour periods. They are most active between 1200 and 1800 hours, and most individuals sleep between 0600 and 1200. Brown-throated three-toed sloths exhibit two different resting modes. The first is that of an "awake-alert" state during which the animal's eyes are actively open and blinking; the second is that of a "behavioral sleep", during which the animal's eyes are closed but still remains suspended from a tree. Adults have never been observed in the same tree with another adult. Agnostic behavior is relatively rare between conspecifics; however, they readily protect territory, food, or other resources. (Duarte, et al., 2003; Gilmore, et al., 2001; Greene, 1989)
- Average territory size
- 20000 m^2
The average home ranges of brown-throated three-toed sloths is less than 2 hectares. There is no further information on the home range of this species. (Gilmore, et al., 2001)
Communication and Perception
Cercropia (e.g., embauba). They consume various parts of the tree, including leaves, flowers, and fruits. is a facultative drinker and receives most of its water from ingested plant materials. (Bezerra, et al., 2007; Duarte, et al., 2003; Gilmore, et al., 2000)is a strict herbivore that feeds primarily on trees in the genus
- Plant Foods
Brown-throated three-toed sloths are highly camouflaged and slow-moving, both of which help decrease risk of predation via decreased visibility. Major predators of this species include spectacled owls, harpy eagles and a variety of felid species. Brown-throated three-toed sloths descend from the canopy to defecate and urinate on the ground. Although they only descend from teh canopy once every 3 to 8 days, this behavior greatly increases vulnerability to predation. (Gilmore, et al., 2001; Touchton, et al., 2002; Voirin, et al., 2009)
- Anti-predator Adaptations
Brown-throated three-toed sloths have are mutualists with algae, which reside in the coats of sloths. The presence of algae confers a greenish tint to the outermost fur coat, which is hypothesized to function as camouflage. It has also been suggested that algae provides essential trace elements and nutrients. In exchange, algae receives shelter in the coats of their host and sunlight, as sloths prefer sections of sun-exposed canopy. Brown-throated three-toed sloths are primary prey for a number of vertebrate predators including harpy eagles and many species of felid; however, they do not make up a large portion of any one species' diet. Known parasites of this species include Leishmania and Pneumocystis carinii. (Gilmore, et al., 2001)
- Ecosystem Impact
- creates habitat
- algae, (Chlorophyta)
- algae, (Chrysophyta)
- algae, (Cyanophyta)
- algae, (Rhodophyta)
- trypanosomatid protozoans, (Leishmania)
- fungus, (Pneumocystis carinii)
Economic Importance for Humans: Positive
There are no known positive effects ofon humans.
Economic Importance for Humans: Negative
There are no known adverse effects ofon humans.
Hee-Jin Jung (author), The College of New Jersey, Matthew Wund (editor), The College of New Jersey, John Berini (editor), Animal Diversity Web Staff.
living in the southern part of the New World. In other words, Central and South America.
uses sound to communicate
Referring to an animal that lives in trees; tree-climbing.
- bilateral symmetry
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
uses smells or other chemicals to communicate
having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.
- active during the day, 2. lasting for one day.
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
- female parental care
parental care is carried out by females
union of egg and spermatozoan
an animal that mainly eats leaves.
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
an animal that mainly eats fruit
An animal that eats mainly plants or parts of plants.
Having one mate at a time.
having the capacity to move from one place to another.
- native range
the area in which the animal is naturally found, the region in which it is endemic.
active during the night
rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.
Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).
remains in the same area
reproduction that includes combining the genetic contribution of two individuals, a male and a female
a wetland area that may be permanently or intermittently covered in water, often dominated by woody vegetation.
uses touch to communicate
Living on the ground.
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
uses sight to communicate
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
- year-round breeding
breeding takes place throughout the year
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