Facts About Two and Three Toed Sloths

Appearance:

They have long gray or brown hair that blends in well with the surrounding environment, making it difficult for predators, such as the jaguar, to see them. This hair curves in the opposite direction of most other mammals: from the stomach to the back. Their hair is often covered with a coat of blue-green algae during the rainy season. This algae provides camouflage. They grow to a length of between one and a half and two and a half feet (in about 2 1/2 years). Their ancestor, the Giant Ground Sloth, which lived before the last ice age, reached the size of the modern elephant. Click here for information on the Giant Ground Sloth and other extinct sloth ancestors

Food and Drink:

They eat leaves and buds. The two-toed species also eat twigs, fruits, and small prey. Their low rate of metabolism enables them to live on relatively little food. They do not have incisors and crop leaves with their hard lips. Their teeth grow continuously, as they are worn down by the grinding of their food. They don't drink but get their water from eating juicy leaves & licking dewdrops.

Defense:

They can defend themselves with sharp claws, but their main form of protection is their camouflage. Predators, beside people, include large snakes, harpy and other birds. Also, jaguars and ocelots are a danger when the sloth is on the ground. On the ground it moves extremely slowly. Surprisingly, sloths are good swimmers.

Gestation/Birth:

A sloth's gestation period is almost six months. The newborn is about 10 inches (25 cm) long, and weighs about 12 oz (350g). It clings to its mother until about 5 weeks old.

What They Do Upside Down:

They do most things upside down: eat, sleep (an average of 15 hours per day), mate, and give birth. Because of their upside down life, many of their internal organs (liver, stomach, spleen, pancreas) are in different positions from other mammals. Sloths sometimes let out a cry or hissing sound.

Difference Between Two and Three Toed Sloths:

Besides the fact that one has two toes on its forelimbs and the other three, they have different numbers of vertebrae (three-toed ones have nine; two-toed ones have six or seven). Also, Three-toed sloths have a small tail and its forelegs are substantially longer than the rear ones. The two-toed sloths do not have tails and its front and back legs are closer to the same size.. The two-toed variety also has a shorter neck, larger eyes and move more between trees. (sloths switch trees for new leaves to eat).

Going to the Ground:

During the rare times they go down to the ground (such as to change trees for food), they move very slowly.

Lifespan:

The probable maximun sloth lifespan is between 30 and 40 years. Some sloths in zoos have reached these ages.

Sloth Scientific Classification and Areas Inhabited:

Order: Xenarthra (Encyclopedia Britannica says the order Edentata
Suborder: Pilosa

Family: Megalonychidae/Choloepidae
Genus: Choloepus (Two-toed Sloth)
Species:
1. True Two-toed Sloth or Unau (Choloepus didactylus). Located in the forests of northern South America.
2. Hoffman's Two-toed sloth (choloepus hoffmanni). Lives in areas from Nicaragua to Peru and Brazil.

Family: Bradypodidae
Genus: Bradypus (Three-toed Sloth)
Species:
1. True three-toed sloths or ai or (bradypus tridactylus). Lives in areas from Central America to Northern Argentina.
2. Brown throated three-toed sloth (Bradypus variegatus). Lives in areas from Guatemala to Honduras.
3. Maned Sloth (Bradypus torquatus). Only found in Eastern Brazil. The most rare of the five species.

Source: Grzimek's Encyclopedia of Mammals, Volume 2, McGraw-Hill Publishing Company, 1990, Sybil P. Parker, Editor.