Themes in Global Environmental History - Sloths

Introduction

Sloth is a habitual and slow-moving animal; hence it is known to be lazily living lazily on the tree, inhabiting in the Central and South America. The animal has been in America for more than 60 million years. About 12,000 years ago, many of the sloth species were dwelling on the ground, whereas most of them especially Megatherium were the size of an elephant. The animal is characterized to be having the long claws that it inhibits its stable walk on the ground, and leaving it to crawl on the tree branches. They use their long claws to hang on branches to promote its ability to feast the leaves on the tree branches where other animals cannot get. San Diego Zoo enlightens that thousands of years ago, sloths were bigger similar to that of the elephant. The ancient sloths used to roam around North America, before getting extinct in around 10,000 years ago. In the present days, six living species of the tree sloths are in the South America rainforest, and they are closely related to

Is your time best spent reading someone else’s essay? Get a 100% original essay FROM A CERTIFIED WRITER!

Save 25%

Habitat

Although sloth ancestors lived in North America, the modern sloths dwell in the South and Central America, where they are comfortable living in the rain and cloud forest. Sloths have their unique way of sleeping, they prefer sleeping while curled into a ball in the fork of the tropical tree, and sometimes, you may find it sleeping while hanging its claws from the tree branches. Sloth is one of the few animals whose life revolves around sleeping in their tree homes. Hence they are considered to be lazy. Sloth maintains its body temperature as low as 86F-93F, and it regulates the body temperature by moving in and out of the shades to stabilize their body temperature. The canopy trees that sloths spend most of their time protect them with protection from the predators like eagles and jaguar.

Sloth can only consider leaving their home tree when they need to relieve themselves once per week. Sloth do swim, according to Pujos, De Iuliis, and Cartelle, sloth are strong swimmers, and they sometimes do this by dropping down from their tree branches into the water, then they use their extended arms to propel through the water (19). The most notable thing that these animals can do while on the ground is to defecate, and they do so for ecological balance. Besides this purpose, sloths are considered to be much useless when they are on the ground level.

Briggs states that, while in the captive, sloth can spend between 15 to 20 hours sleeping in a day, making them have limited social activities. Though, Briggs adds that they can averagely sleep like a human while they are in the wild. It was strange to note that, even after having their nine hours sleeping time, sloth still do not make any effort to socialize and make friends with other of their species; instead they choose to live solo life (Pujos, De Iuliis, and Cartelle 25). GarcesRestrepo, Pauli, and Peery add that the closest that a sloth can get to social life is when they share the same tree with sleeping, is that not incredible (p.15).

Mating Habits

GarcesRestrepo, Pauli, and Peery affirm that sloth mate in the tree and also give birth to their offspring while on the tree. The courting process begins when the female yells a matting scream that alerts all the males who are within to be aware that she is ready for mating. Interest males will engage in a confrontation that will lead to a fight while they are still hanging on the branches by their feet and pawing at each other. The one who will emerge stronger and the victor will enjoy mating the female. Similar to other mammals, sloth give birth to only one baby at a time. Pujos, De Iuliis, and Cartelle uphold that, sloth can have a gestation period that varies between five to six months, while some types of sloth such as the Hoffman's two-toed sloth; can have up to 11.5 months (30). Once they are born, the babies take long before they leave their mother to live on their own. They spend their early stage of their lives riding around clinging to their mother's belly some weeks after birth (GarcesRestrepo, Pauli, and Peery). They later reach the stage that they no longer hang from their mother, but that does not mean to them that they are mature to independent. Still little sloths spend up to four years living alongside their mothers.

Taxonomy

Sloths fall under the order of Xenarthra, which is a group of placental mammals that are perceived to have evolved in South Africa nearly 60 years ago. A study by Svartman, Stone, and Stanyon found that the xenarthrans split from the other placental animals around 100 years ago, and armadillos and anteaters are also categorized among Xenarthra. The ancient xenarthrans were arboreal herbivores structured with fused pelvises, sturdy vertebral columns, small brains and stubby teeth. Sloths are grouped under the taxonomic suborder Folivora of order Pilosa. The names originate from the Latin name 'leaf eater' and 'hairy' respectively. Pilosa being the least in the orders of the mammals, it's the only other suborder that has the anteaters.

Further, the Folivora divides into five families, whereby, three of them are entirely extinct, and the living species are distributed across the two families, they include:

• Three-toed sloth, having four extant species
• Brown-throated sloth being the most common, it lives in the neotropical eco-zone in the Central and South America forests.

On the other hand, pale-throated sloth dwells in northern South America in the tropical rainforest. They are widely distributed, and they closely resemble the brown-throated sloth; hence they can easily be confused with one another. According to the genetic proof given, the two species diverged almost 6 million years ago.

The maned sloth is only presently located in the Atlantic Forest of southeastern Brazil.

The pygmy three-toed sloth is critically endangered species and is the is endemic to the small island of Isla Escudo de Veraguas off the coast of Panama.

Megalonychidae is made up of the extinct genus Megalonyx, then the two-toed sloth genus that is already extinct include:

• Linnaeus's two-toed sloths have their natural habitat in The Guianas, Venezuela, Ecuador, Peru, Colombia as well as Brazil north of the Amazon River.
• Hoffmann's two-toed sloths are found in the tropical forest. They are divided into two ranges that ate split by the Andes. One of the populations dwells in the eastern Honduras, which is in the north to western Ecuador in the south and other in northern Bolivia, eastern Peru, and Brazil.

Anatomy

Sloths are a cat-sized mammal, weighing at an average of 8 to 9 pounds. Its head is short, flat and round shaped tinny ears, short snout, long legs, small eyes and stubby tail. Sloths have coarse, long fur that is grey, but some instance it may appear to be greenish as result of the growing algae on their coats. Rather than having toes, the sloths have three curved claws on their front limbs that they use to hook onto the tree branches and hanging upside-down easily. Sloths have a flexible neck that allows them to rotate their heat at an angle of 90 degrees. Their mouths are shaped in a manner that makes them appear like they are smiling. The distinction in appearance between the male and the female is that the female has a bright orange or yellow patch of fur found between their shoulders.

Sloths are divided into two categories, two-toed and three-toed. Though, it may appear to be much confusing since both have three 'toes' or crawls on their limbs. The 'two-toed' sloth is supposed to be referred to as the 'two-fingered' sloth since both they differ in the appearance of their front limbs. The two-toed sloth is considered to be relatively more prominent compared to the three-toed sloth; however, they both have common features. Their physical size is approximately that of the average-sized dog at nearly 23 to 27 inches (58 to 68 cm) and 17.5 to 18.75 pounds (about 8 kilograms).

Sloths naturally remain motionless and camouflaged off the ground for their safety against the predators. The sloth moves in a languid and sluggish pace due to the extremely slow metabolic rate in their bodies. Averagely, sloth travels about 41 yards per day.

Fossils and Bones

Sloths are known to be having a different vertebrate than other mammals. The configuration of the ground sloth ankle and foot shows that they were typically plantigrade (it means that they used to rest their entire foot surface on the ground). However, the stud by Svartman, Stone, and Stanyon shows that, as early as the 1840s, at least some ground sloths used to walk with the mediolateral foot posture, meaning that the outer margins of the feet supported most of the weight. As per this configuration, it is evident that the dorsal surfaces of the sloths' feet are faced laterally.

Fossils trackways confirm that the sloth's body is pushed by the center of gravity to strengthen their hind limb bones, vertebrae, and pelvis, showing that at least some forms could walk bipedally. Most of the sloths have their hands, as well as hand claws, appearing well suitable for the manipulation of the foliage together with the strong tail is seen in many of the sloths' fossils suggesting that they have sat in a tripodal posture when eating and foraging.

According to the tripodal capacities of the ground, sloths have supported the evidence by the paleontologists working on the tetrapod groups. As mentioned above, the living tree sloths are excellent swimmers. Therefore, it is considerate to state that the ground sloths were too. Although, an isolated group f sloth's fossils indicate the morphological features that prove that they were habitual and not rare swimmers, while the amphibious habit suggests that for both nototheniids and scelidotheriine mylodontids. One group of nototheniid appears to have been genuinely semi-aquatic.

Threat to the Sloth Species

Research by International Union for the Conservation of Nature (IUCN reveals that sloths particularly the Hoffman's two-toed family, are grouped as one with the "least concern" in regards to their population. Sloths endangered species threatened by factors such as habitat loss and illegal trade. Whereas some critics argue that sloth endangerment may not have a direct effect to the world, but it is imperative to note that their loss would be as disastrous as any other extinct species. Sloth has existed on Earth for thousands of year, though, due to the rapid destruction of its habitat in the name of the development, is critically upsetting the delicate balance of the ecosystem. Sloth becomes vulnerable to threat sue to their slowest movement on earth as they are unbearable to walk.

Habitat Loss

As mentioned above, sloths commonly depend on trees for habitat. They rely on the tree on everything, be it sleeping, eating, giving and even mating while hanging on the tree branches. In that case, human activities, mainly deforestation which did for plantation and clearing fields, has posed a threat to the survival of the species soon. By cutting down trees, the habitat of the sloth is destructed in one swoop. Although there has been a decline in deforestation in the Atlantic forest, still it has not stopped. Provided that such blatant destruction of the trees goes on, it will continue to reflect on the sloths that inhabit the forest.

In Colombia, there are some unreported cases where sloths died in large numbers and ignored or unnoticed by the wildlife conservatives. A parallel incidence is the reported case in the newspaper El Colombiano, in Department of Antioquia, it is estimated that the destruction of the forest led to the displacement of 600 B. variegatus from their natural habitat. The species were forced to the beaches and open grasslands where they endured starvation, dehydration and parasite infestation. The local communities took the i...