SLOW AS A SLOTH

Sloths have existed on this planet since prehistoric times. The ground sloth is the ancestor of the modern sloth. The ground sloth lived before the last Ice Age. It was the size of a modern elephant! Presently, there are five different species of sloths. The five species are divided into two main groups. The groups are the two-toed sloths and the three-toed sloths. How can people tell them apart? Well, the two-toed sloths have two claws on their forelimbs and the three-toed sloths have three claws on their forelimbs. By looking at a sloth's hind limbs, it's very hard to determine whether a sloth is a three-toed sloths or two-toed sloth because the hind limbs of any sloth always has three claws. The two-toed sloths are also larger than the three-toed sloths. The only two species that were mentioned in books were the pale-throated three-toed sloths and the giant sloth. Sloths may be considered stupid but, there are many sloths living all around the world, which means that they can survive very well. Since sloths are high up in trees, good at camouflaging, and their sharp claws are good defense it's very hard for predators to find them.

The sloth, unlike any other animal, mostly stays trees. Most sloths in the rainforest hang from tree branches up in the canopy. Sloths live in the Central and Northern parts of South America. Since they are so high up in the canopy, the larger animals cannot reach them. Sloths' sharp claws help them cling on to trees as well as defend themselves. Sharp claws aren't the only things that make it easy for sloths to survive.

The physical apperances of sloths enable it to survive in their habitiats. Sloths have long arms and long claws. Their claws are three to four inches (eight to ten centimeters) long. Even though they have long arms and legs, they can not move quickly due to their weak muscles. All sloths are large, hairy, have strange, rounded heads, and flat faces. Sloths have teeth in their cheeks and hair on their stomachs. The hair is divided the different ways so that rain will run off its sides when it's hanging from branches. There is also blue-green algae growing in the sloth's fur. A male sloth is twenty-nine inches (seventy-four centimeters) all the way from head to rump. The babies are approximately three hundred to four hundred grams at birth, and they are born with brown fur which is mostly unnoticed by people. Babies grow up to one and a half to two and a half feet. Another difference between the three-toed sloths and the two-toed sloths is that the three-toed sloths have very short tails and two-toed sloths don't have tails at all. Since sloths are slow moving animals, the things they eat do not give them much energy.

The food of three-toed sloths are different from the food of two-toed sloths. three-toed sloths have a normal diet and eat only leaves, twigs, and the buds of the Ceropia plant. The two-toed sloths have a varied diet which includes; leaves, shoots, fruits, and other plants. Since each type of food doesn't give the sloths a lot of energy, they have to eat large quantities of food. All sloths eat leaves and small trees. Since sloths are not usually killed by other animals, they don't need to have the ability to move fast.

The three-toed sloths, in particular, is known for its slowness. They also have few, and some say no, competitors for food. Sloths move no faster than 0.6 miles per hour. They take about one month to digest food and have a low metabolic rate, due to little movement. A sloth does most things alone and only communicates during breeding. The male and female find each other by the markings on trees. The urine of a sloth is passed through once a week. The only predator of a sloth is the Harpy Eagle. Since hanging upside down from tree branches keeps a sloth safe, sloths do most things upside down. Like eating, sleeping, mating, and giving birth. At very rare times, sloths go down onto the ground. They move by dragging themselves by the hands since they can't walk on feet but they can stand on their feet. Sloths are highly adapted to all types of leaves. There are many things that help protect sloths and there are many things that a sloth does for its environment.

A sloth does a lot of things to help its environment. Since sloths can protect themselves very well, they're on the top of the food chain . Sloths do a very good job of keeping plant populations under control. One third of a sloth's weight is from leaves!! As well as keeping the population of plants under control, sloths will keep the population of sloths going. They also help populations of insects going. The insects lay eggs in their fur and some insects turn into moths. Then the sloths carry the insects away. The cycle continues and the sloths continue carrying insects. Nine hundred seventy-eight beetles were once found in one living sloth!! Prehistoric sloths were also like modern sloths. They had similar behaviors, ate similar foods, and similar physical appearances.

Prehistoric sloths were sometimes found by archaeologists. In Athens, Georgia, a skeleton of a giant North American sloth was found. According to researchers, the sloth roamed the area about fourteen thousand years ago. It was thirteen feet in length and it weighed two thousand five hundred to three thousand pounds. It took Albert Brantley, a student, three years to reconstruct the skeleton. The giant sloth that was found lived before the last Ice Age. It was nine feet high on all four legs and about twenty feet upright. It ate roots, twigs, and tree leaves. The North American sloths lived in the Central and the Southwestern part of South America. It was the most complete skeleton of a prehistoric animal that was found, though not all the bones were found. Sloths are one of the mammals that lived ever since prehistoric times. If you ever want to feel happy about running a mile, run with a sloth.

-- back to top --

THE WORLD'S MIRACLE: SILKWORMS

Silk wasn't discovered at the beginning of humans. About five thousand years ago, a Chinese Empress, Shiring Chi, strolled through the garden. The Empress got tired of walking and stopped to rest. She saw a strange worm stretched out on a leaf. The worm was actually producing shiny strands from its mouth. The empress took the worm into her living room to observe. She accidentally dropped the worm into her hot cup of tea. The thread around the worm loosened and when Shiring Chi touched it, it was soft and pliable. She thought that this material would make very good fabric. And that's how silk was made. Silk spread to Europe after some time. Europeans selected rough routes so that they could safely carry silk to and from China. They created a six thousand mile long Silk Road. Silk was first manufactured in Korea about three thousand five hundred years ago, at around the Ko Chosun Dynasty. The Ko Chosun Dynasty was approximately at 1500 B.C. Now silk is passed on from generation to generation. There are different species of silkworms and most of them are always used to make silk. The giant silkworm moth is probably the only silkworm that is not often used to make silk. Silk has been here for a long time, which means that silkworms have also been here with us for a long time. Silkworms, the wonderful worm that generated silky thread for us, originated in China.

Silkworms were originally in China but now they are in all of Europe and Asia. They were there since the sixth century A.D. Most silkworms are found in farm yards, trays, and cages. They are domesticated insects and act like any farm yard animal. Before silkworms were domesticated, they were found in mulberry bushes. Now, they're are little amounts of Silkworms that live in the rainforest. In the eighteenth century, they were transported to North America. The color of their threads are white so that people can dye the threads easily.

Silkworms look a little different from other worms. Silkworm moths are light, brown, fat, hairy, and yellow or yellowish-white. The caterpillars are pale, gray, hairless, and they are five to seven centimeters in length (two to three inches). A silkworm, like any other insect, is an invertebrate. Silkworms grow very quickly especially when they are caterpillars. The wingspan of a silkworm moth is two and a half to five centimeters (one to two inches) in length. Most larvae are 0.6 centimeters (0.25 inches) long. Mature larvae are yellowish gray or dark gray. They are 7.5 centimeters (three inches) long. Many of a silkworm's food relate to its physical appearance.

Just like other worms, silkworms will only eat fruits and vegetables. Except for the Chinese Silkworm, all silkworms need to eat a specific type of food in order to generate good quality silk. Silkworm caterpillars that eat mulberry leaves have very fine silk. Most caterpillars eat mulberry leaves. Silkworm moths don't eat at all! Larvae eat mulberry, osage orange, and lettuce. Six weeks after, the larvae comes out of it's cocoon and stops eating. Then they spin their cocoons. Animals eat silkworms as well as silkworm eating other things. Humans and some types of birds will eat silkworms. Domestication have changed a lot of what a silkworm eats and how it acts.

After silkworms have been domesticated, they have lost a lot of their wild behavior. It is not that good for the silkworms but it makes silk production much easier and quicker. Now there are very few silkworms in the world that are wild and many of them live in the rainforest. In the past, female silkworm moths could barley fly since they are full of eggs. So farmers don't have to worry about the female silkworm moths flying away with all the eggs. Now silkworm moths don't fly at all because they have grown fatter and therefore heavier after they domesticated. The female will die almost immediately after she lays the eggs and the male will die shortly after the female dies. A female will lay three hundred to four hundred eggs at one time and there's a type of liquid that the females make to fasten the eggs. After ten days, the eggs will hatch. One fiber of a silkworm is three hundred to nine hundred meters (one thousand to three thousand feet) long! Silkworms are beneficial to humans by making silk for us.

A silkworm's niche is different from other types of worms. Other than producing silk, silkworms keep the population of silkworms going. For over three thousand five hundred years, silkworms create silk for us, make fabric, and many other things that other organisms don't have the ability to make. Silkworms are born with silk but you can't just pick silk off a caterpillar. A female moth will lay hundreds of eggs before she dies and after three weeks, the eggs will hatch and caterpillars come out. After the caterpillar becomes a pupa, it will spin a cocoon covered by its own silk. It is then that silk can be taken. If the cocoons aren't boiled, they will become moths. The life cycle continues. Since silkworms eat mulberry leaves, they damage the mulberry bushes as well as other types of plants that they feed from. They provide food for us, humans, and some species of birds. They help plants by recycling plant nutrients as well, just like any other type of worm. Silkworms have helped us in many ways.

Since silk originated in China, there have been many legends about silkworms. The most common legend is that of a father who let his daughter staying with his stallion for many years. The daughter really missed her father and she told the stallion that she would marry it if it found her father. The stallion brought her father back and started to act very strange around the girl. The girl told her father about her promise to the horse and the father thought that that was out of the question. He felt that if anyone knew about this, they would lose face. The father killed the stallion and left the hide out to tan. One day when the girl was talking with her friend near the hide, the hide wrapped around the girl and they turned into a silkworm.

Silk is one of the main things that silkworms make for us. There are many steps to make silk out of cocoons. The cocoon is picked when it's two centimeters long. In places where they grow cocoons, they sell them to spinners/weavers. Finally cocoons are boiled and thread is removed. The worms are eaten most of the time by people. The thread that is finally made is like soft blond hair. Silk has made up most of human's lives and humans really count on silk!

-- back to top --

SQUEAKY RUBBER

Rubber has helped us make life much easier, but life was made harder for rubber trees ever since we started using rubber. Native South Americans discovered the rubber tree before Columbus' voyage! In 1731, the French government sent Charles Marie De La Condamine to South America. In 1736, he came back with rolls of crude rubber and they soon found out that if you rubbed this material, it could erase pencil marks. Charles Macintosh found a plant, the rubber tree, that made rainproof garments. By 1990, more than fifteen million tons of rubber made. Rubber trees are strange trees that live in different habitats.

Just like most trees, rubber tress live in the rainforests. Rubber trees are mostly in tropical rainforests and they can live well in a variety of soils. It is important for rubber trees to have the ability to adapt to different types of soils or else they would be like maple trees which can only grow in cold climates. That would make it hard to find rubber. Then the simplest materials made of rubber to be rare and it would make life much harder. Some of the attributes of a rubber tree help it survive in many different environments.

The rubber tree's leaves are trifolate which means that the leaves are made up of three sections. That makes it hard for the rain to damage the leaves of a rubber tree and the rubber tree can live for a longer time. Rubber trees grow up to twenty-four centimeters and have flowers or even fruits that have three seed each at sometimes. A tapping cut looks like a spiral and after two to three hours after tapping, the vessels in the rubber tree are clogged. Rubber trees are tapped four years after they are grown.

In order for the rubber tree to produce rubber, they need what any other living organism needs, food. Just like any other plant, a rubber tree needs sunlight and rain. It requires about one hundred fifty to two hundred fifty centimeters of rain through one year. Sometimes, the weather will affect the rubber trees' behavior. If it's too cold, too hot, or too wet, the rubber tree may not be able to survive. So they may have certain behaviors that help prevent that.

A rubber tree's behaviors are strange, and not similar to the behaviors of other trees. Usually after a dry spell, a leaf fall occurs. That is called wintering and after the wintering, flowers appear and sometimes fruits appear as well. Just like any other type of plant, a rubber tree knows how to transport food all around itself. It also know how to get water and nutrients from the ground. Rubber trees are one of the plants that have survived for a long time and humans have used for a long time. Rubber trees are a large part of human life. Think about it, without rubber, we wouldn't be able to do all the things that we used rubber for. Humans ride, walk, sleep, and sit on rubber. Rubber cement is used for adhesive, insulating, friction tapes, and foot wear. Soft rubber is used for conveyor belts. Hard rubber is used for pump housing, pipes, telephones, and the radio. Plain rubber is used for hoses, tires, and rollers. Rubber is also used for electrical resistance like protective gloves, shoes, and blankets. Now think about how life would be without these things... HORRIBLE! As well as for human uses, the rubber tree provides food for all animals. Rubber, unlike money grows on trees. Actually, it grows in trees.

Rubber doesn't come out everyday, people have to tap trees to get rubber out of it. Rubber comes from latex. Rubber trees are tapped every two days. They cut a mark in the bark. It can not be too deep or thick. If that happens, it will reduce the productive life of a tree. After there is a cut in the bark, a container is put under it and latex will flow out. After a few hours, the tapper collects the container. The latex will harden and become a lump. All the scraps are processed and processing destroys many proteins. After being processed, the scraps will become a solid piece (sometimes a sheet). The lumps of latex are also processed and the water is removed during the process. Removing the water makes the latex more rubbery. At the end of the process, sixty percent of the material is rubber and forty percent of the material is water, proteins, etc. Without rubber trees, there wouldn't be rubber. Without rubber, life would be very hard.

-- back to top --

© The content, design, and images of this page are copyrighted by Freda Auyeung since 1997. Please do not remove any content from this page without written permission from the author. You can send any questions, comments, concerns my way.