4/13/2022

A Sloths Life Cycle

Sloth
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The sloth, known for its sluggishness, has carved out a clever mode of life as a kind of walking ecosystem, but its lifestyle does constrain its energy level. A Sloths life cycle. A cath is a baby sloth.Middle aged sloths are in Sids range from the Original mov ie Ice Age. An adult soths is in its 30s or maybe 40s. Powered by Create your own unique website with customizable templates.

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Alfred L. Gardner
Curator, New World Mammals, National Museum of Natural History, Smithsonian Institution, Washington D.C. Wildlife Biologist, Patuxent Wildlife Research Center, United States Geological Survey, Laurel,...
Alternative Titles: Phyllophaga, tree sloth

Sloth, (suborder Phyllophaga), tree-dwelling mammal noted for its slowness of movement. All five living species are limited to the lowland tropical forests of South and Central America, where they can be found high in the forest canopy sunning, resting, or feeding on leaves. Although two-toed sloths (family Megalonychidae) are capable of climbing and positioning themselves vertically, they spend almost all of their time hanging horizontally, using their large hooklike extremities to move along branches and vines. Three-toed sloths (family Bradypodidae) move in the same way but often sit in the forks of trees rather than hanging from branches.

What kind of animal is a sloth?

Sloths are mammals. They are part of the order Pilosa, which is also home to anteaters. Together with armadillos, sloths and anteaters form the magnorder Xenarthra.

How many types of sloths are there?

A total of five species of sloths exist: the pygmy three-toed sloth, the maned sloth, the pale-throated three-toed sloth, the brown-throated three-toed sloth, and Linnaeus's two-toed sloth. All sloths are either two-toed or three-toed.

Where do sloths live?

Sloths live in the lowland tropical areas of South and Central America. They spend most of their life in the forest canopy. Two-toed sloths tend to hang horizontally from branches, while three-toed sloths often sit in the forks of trees.

What do sloths eat?

Sloth

Sloths are omnivores. Because they spend most of their time in trees, they like to munch on leaves, twigs, flowers, and other foliage, though some species may eat insects and other small animals.

Why are sloths so slow?

Sloths are slow because of their diet and metabolic rate. They eat a low-calorie diet consisting exclusively of plants, and they metabolize at a rate that is only 40–45 percent of what is expected for mammals of their weight. Sloths must move slowly to conserve energy.

Sloths have long legs, stumpy tails, and rounded heads with inconspicuous ears. Although they possess colour vision, sloths’ eyesight and hearing are not very acute; orientation is mainly by touch. The limbs are adapted for suspending the body rather than supporting it. As a result, sloths are completely helpless on the ground unless there is something to grasp. Even then, they are able only to drag themselves along with their claws. They are surprisingly good swimmers. Generally nocturnal, sloths are solitary and are aggressive toward others of the same sex.

Sloths have large multichambered stomachs and an ability to tolerate strong chemicals from the foliage they eat. The leafy food is digested slowly; a fermenting meal may take up to a week to process. The stomach is constantly filled, its contents making up about 30 percent of the sloth’s weight. Sloths descend to the ground at approximately six-day intervals to urinate and defecate (see Sidebar: A moving habitat). Physiologically, sloths are heterothermic—that is, they have imperfect control over their body temperature. Normally ranging between 25 and 35 °C (77 and 95 °F), body temperature may drop to as low as 20 °C (68 °F). At this temperature the animals become torpid. Although heterothermicity makes sloths very sensitive to temperature change, they have thick skin and are able to withstand severe injuries.

All sloths were formerly classified in the same family (Bradypodidae), but two-toed sloths have been found to be so different from three-toed sloths that they are now classified in a separate family (Megalonychidae).

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Three-toed sloths

The three-toed sloth (family Bradypodidae) is also called the ai in Latin America because of the high-pitched cry it produces when agitated. All four species belong to the same genus, Bradypus, and the coloration of their short facial hair bestows them with a perpetually smiling expression. The brown-throated three-toed sloth (B. variegatus) occurs in Central and South America from Honduras to northern Argentina; the pale-throated three-toed sloth (B. tridactylus) is found in northern South America; the maned sloth (B. torquatus) is restricted to the small Atlantic forest of southeastern Brazil; and the pygmy three-toed sloth (B. pygmaeus) inhabits the Isla Escudo de Veraguas, a small Caribbean island off the northwestern coast of Panama.

Although most mammals have seven neck vertebrae, three-toed sloths have eight or nine, which permits them to turn their heads through a 270° arc. The teeth are simple pegs, and the upper front pair are smaller than the others; incisor and true canine teeth are lacking. Adults weigh only about 4 kg (8.8 pounds), and the young weigh less than 1 kg (2.2 pounds), possibly as little as 150–250 grams (about 5–9 ounces) at birth. (The birth weight of B. torquatus, for example, is only 300 grams [about 11 ounces].) The head and body length of three-toed sloths averages 58 cm (23 inches), and the tail is short, round, and movable. The forelimbs are 50 percent longer than the hind limbs; all four feet have three long, curved sharp claws. Sloths’ coloration makes them difficult to spot, even though they are very common in some areas. The outer layer of shaggy long hair is pale brown to gray and covers a short, dense coat of black-and-white underfur. The outer hairs have many cracks, perhaps caused by the algae living there. The algae give the animals a greenish tinge, especially during the rainy season. Sexes look alike in the maned sloth, but in the other species males have a large patch (speculum) in the middle of the back that lacks overhair, thus revealing the black dorsal stripe and bordering white underfur, which is sometimes stained yellow to orange. The maned sloth gets its name from the long black hair on the back of its head and neck.

Three-toed sloths, although mainly nocturnal, may be active day or night but spend only about 10 percent of their time moving at all. They sleep either perched in the fork of a tree or hanging from a branch, with all four feet bunched together and the head tucked in on the chest. In this posture the sloth resembles a clump of dead leaves, so inconspicuous that it was once thought these animals ate only the leaves of cecropia trees because in other trees it went undetected. Research has since shown that they eat the foliage of a wide variety of other trees and vines. Locating food by touch and smell, the sloth feeds by hooking a branch with its claws and pulling it to its mouth. Sloths’ slow movements and mainly nocturnal habits generally do not attract the attention of predators such as jaguars and harpy eagles. Normally, three-toed sloths are silent and docile, but if disturbed they can strike out furiously with the sharp foreclaws.

Reproduction is seasonal in the brown- and pale-throated species; the maned sloth may breed throughout the year. Reproduction in pygmy three-toed sloths, however, has not yet been observed. A single young is born after less than six months’ gestation. Newborn sloths cling to the mother’s abdomen and remain with the mother until at least five months of age. Three-toed sloths are so difficult to maintain in captivity that little is known about their breeding behaviour and other aspects of their life history.

Quick Facts
related topics

A sloth's life seems pretty sweet, right? You get to hang out in trees all day, munching on food, sleeping all the time, and moving real slow to blend in with your surroundings. For a sloth, Sunday is every day. Laziness is just the sloth way.

While this might sound luxurious, scientists have revealed that all this chill comes crashing down once a week when a sloth has to take a poop - an ordeal that's more akin to childbirth than a quick trip to the restroom.

You've probably never given much thought to the pooping habits of sloths, and we can't blame you. But you should, because it's generally pretty horrifying. It turns out that one of the side effects is all that slow movement – some meals can take sloths up to a month to digest – is a really sluggish bowel system.

Not only do sloths only poop once a week – more than enough time to cause some serious constipation – they also have to do so on the ground, making them an easy target for predators.

Though, after watching the video below, captured by Bittel at the National Aviary, predators might be too shocked to even approach. (We're not sure about your boss's stance on sloth pooping videos, but consider it NSFW):

According to Jason Bittel at The Washington Post, a sloth can lose one-third of its body weight from pooping, and that amount of faeces is no fun to push out.

'You can watch their stomachs physically shrink as they poo,' sloth biologist Rebecca Cliffe from Swansea University in the UK told him. Oh, and it all comes out in one push.

Sloth Behavior

Pooping is really the only reason for a sloth to ever leave its tree, and it's the only time they have to stand upright. According to Cliffe, once sloths make their way down from their trees, they do a 'poo dance' to dig a small hole to go in.

After the deed is done, they do another little dance to slightly cover it up, before heading back up, presumably feeling a whole lot lighter than they were on the way down.

Since pooping is something all animals do in one form or another, why do sloths wait such a long time between bowel movements, and why do they risk their lives, when they could easily just rain poo down from the tree tops like other canopy dwellers do?

In short, no one really knows. Bittel says that one of the best hypotheses – posed by a team of researchers from the University of Wisconsin back in 2014 – is that sloths poop in such a weird way to keep a balance between them and moths.

Facts About Sloths

The team suggests that, in a weird symbiotic relationship, moths that live on sloths help fertilise a type of algae in the sloths' fur. This algae is important to a sloth's survival because it gives the fur a greenish hue – camouflaging the creature from predators – and possibly providing nutrients when eaten or absorbed through the sloth's skin.

So the sloths might go down to the ground to poop so they can provide a place for the moths to lay eggs, ensuring their life cycle.

Though, according to Cliffe, this hypothesis doesn't really hold up to scrutinty, because of the danger a sloth faces on the ground – over half of all sloths die while outside of their trees – and sloths bred in captivity do not need moths or algae to survive, and still do it anyway. Instead, she says that it may have to do with sex.

What Is A Sloths Life Cycle

'Whatever is going on, it's got to be kind of life or death for survival,' she told The Washington Post. 'In my brain, that tells me that it's probably something to do with reproduction, because that is the driving fact behind most animals' crazy behaviours.'

The general idea behind this, Cliffe says, is to mark a tree for other sloths, basically alerting them that a fertile female is waiting in the canopy above, though more research is needed before any sort of conclusion can actually be drawn.

The moral of this story is that we should be thankful that our bodies pass waste in a much less painful and dangerous way than a sloth. (And if you relate way too much to the sloth experience, then you might want to get that checked out).

Sloths Lifespan

A version of this article was first published in June 2016.