SCIENCE FOR CHILDREN

GLOBAL WARMING

We cannot live without energy. We need food for energy. We cannot cook our food without energy like gas or firewood or coal. To go from one place to another we need petrol or diesel. There are factories that need more energy to run machines. They use petrol, diesel, or coal. When we burn gas, firewood, petrol, or diesel we get two things - energy and carbon dioxide. We use energy. What do we do with carbon dioxide? We don't use it. We allow it to go and mix with atmosphere. The more we use energy, the more carbon dioxide is added to our atmosphere.

Carbon dioxide is a chemical. All chemicals react. The carbon dioxide in the atmosphere absorb heat from the sun and reacts. It reacts by radiating more heat. The more carbon dioxide we send, the more heat we add to the atmosphere. The atmosphere of the globe becomes warm. Every year our globe becomes warmer and warmer.

What will happen if global warming continues? Global warming will melt more ice. More water will be added to sea. Sea level will rise. All low-lying lands will be submerged into water. People living on the coastal regions will have to move to safer places. Desert area are will increase. New deserts will decrease agricultural land.

Many animals and birds have already moved to other places because of these new desert-like conditions. All animals cannot move to new places so easily. Such animals will disappear. Trees and plants cannot move like animals or birds. Expanding deserts will make them disappear from this earth.

What can we do to reduce global warming? The easiest way is to plant more trees. Trees absorb carbon dioxide to produce their food. We want oxygen. Trees and plants take carbon dioxide and give us oxygen. There is a balance in this beautiful nature. When we destroy it, we destroy ourselves.

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GREENHOUSE EFFECT

The sun is our primary energy source. The Sun is a burning star. It is so hot that we can feel its heat from over 150 million kilometers away. Its rays enter our atmosphere and heat our planet. About one third of this solar energy is reflected back into the universe. The shimmering glaciers, water and other bright surfaces
reflect back this heat. One third of this heat is sent back to atmosphere. Two thirds, however, are absorbed by the Earth, thus warming land, oceans, and atmosphere.



The heat that is sent back out into space is stored in the atmosphere. This process is called the greenhouse effect. Without it, the Earth’s average temperature would be a chilling -18 degrees Celsius, even despite the sun’s constant energy supply.



In a world like this, life on Earth would probably have never emerged from the sea. Thanks to the greenhouse effect, however, heat emitted from the Earth is trapped in the atmosphere, providing us with a comfortable average temperature of 14 degrees.

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GREENHOUSE EFFECT


Some of the activities of man also produce greenhouse gases. These gases keep increasing in the atmosphere. The balance of the greenhouse gases changes and this has effects on the whole of the planet.

Burning fossil fuels - coal, oil and natural gas - releases carbon dioxide into the atmosphere. Cutting down and burning trees also produces a lot of carbon dioxide.

A group of greenhouse gases called the chlorofluorocarbons, - which are usually called CFCs, because the other word is much too long! - have been used in aerosols, such as hairspray cans, fridges and in making foam plastics. They are found in small amounts in the atmosphere. They are dangerous greenhouse gases because small amounts can trap large amounts of heat.

Because there are more and more greenhouse gases in the atmosphere, more heat is trapped which makes the Earth warmer. This is known as GLOBAL WARMING.

A lot of scientists agree that man's activities are making the natural greenhouse effect stronger. If we carry on polluting the atmosphere with greenhouse gases, it will have very dangerous effects on the Earth.



THE EFFECTS

With more heat trapped on Earth, the planet will become warmer, which means the weather all over Earth will change. For example, summers will get hotter, and winters too. This may seem a good idea, but the conditions we are living in are perfect for life, and a large rise in temperature could be terrible for us and for any other living thing on Earth.

At the moment, it is difficult for scientists to say how big the changes will be and where the worse effects will occur.

The Weather



In different parts of the world, the effects of weather will be different, some places will become drier and others will be wetter. Although most areas will be warmer, some areas will become cooler. There may be many storms, floods and drought, but we do not know which areas of the world will be affected.

All over the world, these weather changes will affect the kind of crop that can be grown. Plants, animals and even people may find it difficult to survive in different conditions.

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Weather
Weather describes whatever is happening outdoors in a given place at a given time. Weather is what happens from minute to minute. The weather can change a lot within a very short time. For example, it may rain for an hour and then become sunny and clear. Weather is what we hear about on the television news every night. Weather includes daily changes in precipitation, barometric pressure, temperature, and wind conditions in a given location. What is your weather like today?

Climate
Climate describes the total of all weather occurring over a period of years in a given place. This includes average weather conditions, regular weather sequences (like winter, spring, summer, and fall), and special weather events (like tornadoes and floods). Climate tells us what it's usually like in the place where you live. San Diego is known as having a mild climate, New Orleans a humid climate, Buffalo a snowy climate, and Seattle a rainy climate. How would you describe the climate where you live?

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CAN WE CHANGE CLIMATE

It may seem hard to believe that people can actually change the Earth’s climate. But scientists think that the things people do that send greenhouse gases into the air are making our planet warmer.

Once, all climate changes occurred naturally. However, during the Industrial Revolution, we began altering our climate and environment through agricultural and industrial practices. The Industrial Revolution was a time when people began using machines to make life easier. It started more than 200 years ago and changed the way humans live. Before the Industrial Revolution, human activity released very few gases into the atmosphere, but now through population growth, fossil fuel burning, and deforestation, we are affecting the mixture of gases in the atmosphere.

Since the Industrial Revolution, the need for energy to run machines has steadily increased. Some energy, like the energy you need to do your homework, comes from the food you eat. But other energy, like the energy that makes cars run and much of the energy used to light and heat our homes, comes from fuels like coal and oil – fossil fuels. Burning these fuels releases greenhouse gases.

When Do You Send Greenhouse Gases into the Air?

Whenever you ...
Watch TV

Use the Air Conditioner

Turn on a Light

Use a Hair Dryer

Ride in a Car

Play a Video Game

Listen to a Stereo

Wash or Dry Clothes

Use a Dish Washer

Microwave a Meal




... you are helping to send greenhouse gas into the air.

To perform many of these functions, you need to use electricity. Electricity comes from power plants. Most power plants use coal and oil to make electricity. Burning coal and oil produces greenhouse gases.

Other things we do send greenhouse gases into the air too;

The trash that we send to landfills produces a greenhouse gas called methane. Methane is also produced by the animals we raise for dairy and meat products and when we take coal out of the ground. Whenever we drive or ride in a car, we are adding greenhouse gases to the atmosphere. And, when factories make the things that we buy and use everyday, they too are sending greenhouse gases into the air.

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Climate change may be a big problem, but there are many little things we can do to make a difference. If we try, most of us can do our part to reduce the amount of greenhouse gases that we put into the atmosphere. Many greenhouse gases come from things we do every day. As we have learned, these greenhouse gases trap energy in the atmosphere and make the Earth warmer.

Driving a car or using electricity is not wrong. We just have to be smart about it.Some people use less energy by carpooling. For example, four people can ride together in one car instead of driving four cars to work. Here are some additional ways you can help make the planet a better place!

Read
Learning about the environment is very important. There are many good books that will help you learn. To get started, ask a teacher or a librarian for some suggestions. You also can look at the Links page to find other good web sites with information about the environment and climate change.


Save Electricity
Whenever we use electricity, we help put greenhouse gases into the air. By turning off lights, the television, and the computer when you are through with them, you can help a lot.

Bike, Bus, and Walk
You can save energy by sometimes taking the bus, riding a bike, or walking.

Talk to Your Family and Friends
Talk with your family and friends about climate change. Let them know what you've learned.

Plant Trees
Planting trees is fun and a great way to reduce greenhouse gases. Trees absorb carbon dioxide, a greenhouse gas, from the air.

Recycle
Recycle cans, bottles, plastic bags, and newspapers. When you recycle, you send less trash to the landfill and you help save natural resources, like trees, oil, and elements such as aluminum.

When You Buy, Buy Cool Stuff
There are lots of ways we can improve the environment. One of the ways to reduce the amount of greenhouse gases that we put into the air is to buy products that don't use as much energy. By conserving energy, we help reduce climate change and make the Earth a better place. Some products – like certain cars and stereos – are made specially to save energy.

Some Things to Think About
Did you know that you can help the environment if you buy recyclable products instead of non-recyclable ones? Look for the recycle mark – three arrows that make a circle – on the package. Recyclable products are usually made out of things that already have been used. It usually takes less energy to make recycled products than to make new ones. The less energy we use, the better.

Solar Energy
Imagine that it's a hot summer day. You put a scoop of ice cream on the sidewalk, and it melts. Why? Well, you probably know that the sun causes the ice cream to melt. But you may not know that the sun produces solar energy. Solar energy is a fancy way of saying "energy that comes from the sun." Solar energy can be used to heat homes, buildings, water, and to make electricity. Today, more than 200,000 houses in the United States take advantage of the sun's energy.

Cars
Cars are an important part of life for most people. But cars also cause pollution and release a lot of greenhouse gases into the air. Fortunately, there are some cars that are better for the environment. These cars can travel longer on a smaller amount of gasoline. They don't pollute as much, either. Using these kinds of cars can help reduce the amount of greenhouse gases in the air.

ENERGY STAR®
Many things, like computers, TVs, stereos, and VCRs, have special labels on them. The label says "Energy" and has a picture of a star. Products with the ENERGY STAR® label are made to save energy. Buying products with ENERGY STAR® labels will help protect the environment.

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THE WATER CYCLE

Water on Earth is always changing. Its repeating changes make a cycle. As water goes through its cycle, it can be a solid (ice), a liquid (water), or a gas (water vapor). Ice can change to become water or water vapor. Water can change to become ice or water vapor. Water vapor can change to become ice or water.



How do these changes happen? Adding or subtracting heat makes the cycle work. If heat is added to ice, it melts. If heat is added to water, it evaporates. Evaporation turns liquid water into a gas called water vapor.

If heat is taken away from water vapor, it condenses. Condensation turns water vapor into a liquid. If heat is taken away from liquid water, it freezes to become ice.

The water cycle is called the hydrologic cycle. In the hydrologic cycle, water from oceans, lakes, swamps, rivers, plants, and even you, can turn into water vapor. Water vapor condenses into millions of tiny droplets that form clouds. Clouds lose their water as rain or snow, which is called precipitation. Precipitation is either absorbed into the ground or runs off into rivers. Water that was absorbed into the ground is taken up by plants. Plants lose water from their surfaces as vapor back into the atmosphere. Water that runs off into rivers flows into ponds, lakes, or oceans where it evaporates back into the atmosphere.

The cycle continue
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THE ORIGIN OF THE SEA

In popular language, "ocean" and "sea" are used interchangeably. Today's seas are the North and South Pacific, North and South Atlantic, Indian and Arctic Oceans and the Antarctic waters or seas.
Scientists believe that the seas are as much as 500 million years old because animals that lived then occur as fossils in rocks which once were under ancient seas. There are several theories about the origin of the seas, but no single theory explains all aspects of this puzzle. Many earth scientists agree with the hypothesis that both the atmosphere and the oceans have accumulated gradually through geologic time from some process of "degassing" of the Earth's interior. According to this theory, the ocean had its origin from the prolonged escape of water vapor and other gases from the molten igneous rocks of the Earth to the clouds surrounding the cooling Earth. After the Earth's surface had cooled to a temperature below the boiling point of water, rain began to fall and continued to fall for centuries. As the water drained into the great hollows in the Earth's surface, the primeval ocean came into existence. The forces of gravity prevented the water from leaving the planet.

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SOURCES OF THE SALTS...
Sea water has been defined as a weak solution of almost everything. Ocean water is indeed a complex solution of mineral salts and of decayed biologic matter that results from the teeming life in the seas. Most of the ocean's salts were derived from gradual processes such the breaking up of the cooled igneous rocks of the Earth's crust by weathering and erosion, the wearing down of mountains, and the dissolving action of rains and streams which transported their mineral washings to the sea. Some of the ocean's salts have been dissolved from rocks and sediments below its floor. Other sources of salts include the solid and gaseous materials that escaped from the Earth's crust through volcanic vents or that originated in the atmosphere.

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WHY OCEANS ARE ALWAYS BLUE

There are several theories:
Blue wavelengths are absorbed the least by the deep ocean water and are scattered and reflected back to the observer’s eye
Particles in the water may help to reflect blue light
The ocean reflects the blue sky

Most of the time the ocean appears to be blue because this is the color our eyes see. But the ocean can be many other colors depending upon particles in the water, the depth of the water, and the amount of skylight.

The colors we see depend upon the reflection of the visible wavelengths of light to our eyes. The Franklin Institute provides a good explanation of how we see color at http://www.fi.edu/color/color.html.

Wavelengths of light pass through matter differently depending on the material’s composition. Blue wavelengths are transmitted to greater depths of the ocean, while red wavelengths are absorbed quickly. Water molecules scatter blue wavelengths by absorbing the light waves, and then rapidly reemitting the light waves in different directions. That is why there are mostly blue wavelengths that are reflected back to our eyes.

Sometimes oceans look green. This may be because there is an abundance of plant life or sediment from rivers that flow into the ocean. The blue light is absorbed more and the yellow pigments from plants mix with the blue light waves to produce the color green.

Sometimes parts of the oceans will look milky brown after a storm passes. This is because winds and currents associated with the storm churn up sand and sediment from the rivers that lead into the oceans.

The ocean may also reflect the blue sky. However this is prominent only at relatively low angles and when the water is smooth.

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Water bodies

That's because more than two-thirds of our planet's surface is covered by water. We have many different names for the areas of water that cover the earth. We call them ponds, lakes, streams, rivers, seas, and oceans. The biggest ones are the oceans, and there are five of them: the Atlantic,. . . "

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THE ROCK CYCLE


Rock Cycle is a group of changes. Igneous rock can change into sedimentary rock or into metamorphic rock. Sedimentary rock can change into metamorphic rock or into igneous rock. Metamorphic rock can change into igneous or sedimentary rock.

Igneous rock forms when magma cools and makes crystals. Magma is a hot liquid made of melted minerals. The minerals can form crystals when they cool. Igneous rock can form underground, where the magma cools slowly. Or, igneous rock can form above ground, where the magma cools quickly.



When it pours out on Earth's surface, magma is called lava. Yes, the same liquid rock matter that you see coming out of volcanoes.

On Earth's surface, wind and water can break rock into pieces. They can also carry rock pieces to another place. Usually, the rock pieces, called sediments, drop from the wind or water to make a layer. The layer can be buried under other layers of sediments. After a long time the sediments can be cemented together to make sedimentary rock. In this way, igneous rock can become sedimentary rock.

All rock can be heated. But where does the heat come from? Inside Earth there is heat from pressure (push your hands together very hard and feel the heat). There is heat from friction (rub your hands together and feel the heat). There is also heat from radioactive decay (the process that gives us nuclear power plants that make electricity).

So, what does the heat do to the rock? It bakes the rock.

Baked rock does not melt, but it does change. It forms crystals. If it has crystals already, it forms larger crystals. Because this rock changes, it is called metamorphic. Remember that a caterpillar changes to become a butterfly. That change is called metamorphosis. Metamorphosis can occur in rock when they are heated to 300 to 700 degrees Celsius.

When Earth's tectonic plates move around, they produce heat. When they collide, they build mountains and metamorphose (met-ah-MORE-foes) the rock.

The rock cycle continues. Mountains made of metamorphic rocks can be broken up and washed away by streams. New sediments from these mountains can make new sedimentary rock.

The rock cycle never stops.
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YOU CAN CHANGE CLIMATE

It may seem hard to believe that people can actually change the Earth’s climate. But scientists think that the things people do that send greenhouse gases into the air are making our planet warmer.
Atmosphere
The atmosphere covers the Earth. It is a thin layer of mixed gases which make up the air we breathe. This thin layer also helps the Earth from becoming too hot or too cold, much like clothing does for us. Weather systems, which develop in the lower atmosphere, are driven by heat from the sun, the rotation of the Earth, and variations in the Earth's surface.

Oceans
Oceans cover about 70 percent of Earth's surface. Their large mass and thermal
properties, enable them to store vast quantities of heat. Oceans buffer and regulate temperature – energy absorbed or lost by the oceans results in a smaller surface temperature change than would occur over land. The atmosphere and ocean constantly exchange energy and matter. For example, water evaporates from the oceans into the atmosphere. This moisture then falls back to the Earth as precipitation – rain, snow, sleet, and even the morning dew on the grass.

Land
Land covers 27 percent of Earth's surface, and land topography influences weather patterns. For example, the weather in areas covered by mountains can be completely different than the weather in areas where the land is mostly flat.

Ice
Ice is the world's largest supply of freshwater. It covers the remaining 3 percent of Earth's surface including most of Antarctica and Greenland. Because ice is highly reflective and because of its insulating properties, ice plays an important role in regulating climate.

Biosphere
The biosphere is that part of Earth's atmosphere, land, oceans that supports any living plant, animal, or organism. It is the place where plants and animals, including humans, live. Large quantities of carbon dioxide are exchanged between the land-based biosphere and the atmosphere as plants take in carbon dioxide and give off oxygen, and animals inhale oxygen and exhale carbon dioxid.

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THE SUN

Without the Sun here would be no light or life on the Earth.

The Sun is the nearest star to the Earth. It is a storehouse of hot gases, mainly hydrogen. It is so large that 1,300, 000 planet Earths would fit inside it. Inside its core, its heat is 27 million Fahrenheit. Nuclear reactions are converting the hydrogen into helium. In the process, huge amounts of energy are produced. This energy, after tens of thousands of years, reach the sun's surface. Once the energy comes to the surface, it escapes into space as heat, light, and other types of radiations. We need the light and heat on this earth. The other radiations, such as ultraviolet rays, can be harmful. The Earth's atmosphere shield us from much of this harmful radiations.

The surface of the sun is called the photosphere. It is cooler, around 9,932 F. The photosphere is not solid Immediately above the sun's surface is the chromosphere. It is a layer of hydrogen and helium. This layer is 5,000 km thick. This layer merges into the outer layer of atmosphere, and this place is called corona. This corona stretches for millions of miles into space. It is very thin and hot. Its heat is around 5.4 million F. It gives off a constant stream of particles, called the solar wind. This solar wind travels through the solar system
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CONSTELLATIONS

From anywhere on the Earth we can look into the sky and see pinpoints of light. These tiny points of light are all stars. All these stars are part of our galaxy. Our galaxy is called the Milky Way. When you look at the night sky, you will see clear patterns in the sky. Astronomers use these patterns to find their way around. They draw imaginary pictures around the star patterns. These imaginary pictures help them to remember these stars. The first pictures was created four thousand years ago. We still use them.

The canvas of sky is divided into 88 pieces. Each piece is a constellation. And each constellation has a star pattern with an imaginary picture. The Greek astronomer Ptolemy (100-170 A.D.) listed the 48 constellations. Astronomers use these constellations with their star patterns.

The pictures in the sky are of different shapes. They include humans, animals, sea creatures, and tools of the artis and scientist. Ptolemy in his book Almagest lists the 48 pictures people were using in those days. These pictures were taken from Greek mythology. Orion, the hunter, Pegasus, the flying horse, and the Centaur who is half-man and half-horse were included in the sky pictures. The other 40 constellations were created in more recent times.

We cannot see all the 88 constellation from one place on the Earth. The Earth rotates on its axis once a day, and goes around the Sun once a year. Because of the rotation of the Earth, we cannot see all the constellations.

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THE SOLAR SYSTEM

The solar system is the Sun and the family of objects that go around it. These objects stay together because of the sun's gravity. The sun is the largest object in this system. It contains over 95 percent of the solar system material. Out of the remaining material are made all those objects that orbit the sun. These orbiting objects are nine planets, more than 130 moons, billions of asteroids, and billions of comets.

Because of the huge size of the sun, it has huge gravitational pull. This gravitational pull keeps the solar system together and controls the movements of the planets.

Mercury, Venus, Earth, Neptune, and Mars are closer to the sun, and they are rocky. Farther away from the sun are Jupiter, Saturn, Uranus, and Neptune. As they are far away from the sun, these planets are colder and gaseous.

The distance in solar system is measured in Astronomical Units (AU). One AU is 93 million miles.

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COMETS

Comets are snowballs. Vast numbers of them live at the very edge of the solar system. When it travels close to the sun it grows a large head and two tails. Astronomers have estimated that about 10 trillion comets make up the Oort Cloud. It is a huge spherical cloud that surrounds our solar system. This cloud is 4.7 trillion miles wide. Comets are potato-shaped balls of ice and rocky dust, and each one is only a few miles wide.

Occasionally a comet leaves the Oort Cloud and travels into the inner solar system towards the sun. When a comet comes closer to the sun, it grows in size and brightness. The heat of the sun turns the ice into gas, and some dust is released. The gas and dust form a bright head. More gas and dust is blown away and look like two tails. The dust tail is yellowish-white, and the gas tail, bluish.

When a comet is close to the sun and has a head and two tails, it becomes visible from the earth. Some comets keep returning periodically to our sky. The time between its regular returns is called comet's period. Encke's Comet has the shortest period of return of just 3.3 years. Halley's Comet returns every 76 years.
Of the 135 comets, these two are the short-period comets. Others known as long-period comets appear once in thousands of years.

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SECOND LAW OF THERMODYNAMICS

This law is based upon our everyday experience that all hot objects cool down naturally. Heat flows naturally from hot objects to cold objects, but never from the cold objects to hot ones. When two blocks of metal at different temperatures are placed in contact with each other, the fast moving particles of hot block bump into slower particles of the cold block. These collisions transfer energy. In this transfer slower particles speed up and the faster particles slow down. It continues till the heat content is evenly spread between them and their temperature become equal.

In solids their particles are are arranged in fixed position. In crystals, the particles are set in a regular ordered pattern called lattice. When a solid is cold, its particles move or vibrate more slowly. When the temperature is high, the particles move or vibrate more. At lower temperature, the structure is more ordered. Disorder increases as temperature increases.

The particles in liquids are free to move past each other. They are more disordered than solids. Gases are even more disordered than liquids. A gas becomes less disordered if it is compressed. It is because their particles are even father apart.

Entropy

The particles in substances would be most ordered or least disordered at -273.15 C. This is called absolute zero or OK (zero Kelvin). Scientist invented a quantity called "entropy" to measure the amount of disorder in substances. Entropy increases greatly when a solid melts to form a liquid or a liquid boils to form a gas. Machines and living things produce waste heat as they change from from one form to another. This waste heat spreads through the surroundings and increases entropy. It represents energy that does not perform useful work.

As time goes by, the entropy of the universe increases as energy changes produce more and more waste heat. The universe will stop changing when all matter and all energy is uniformly spread.

At the end of time, all the energy in the universe will be in the form of heat that has uniformly spread out. When absolutely everywhere is at the same temperature, heat will not flow, so no work will be done - nothing will happen. Entropy will have reached its maximum value, and the universe will be dead and unchanging.

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THE NATURAL BALANCE

From the tiniest bacterium to the largest mammal. all living things share the planet. These organisms form communities that live together in a balanced state. A community of organisms that lives in a particular area, along with the soil and other nonliving material, forms what is called ecosystem.

Ecosystem can be as small as a water-filled hole in a forest tree or as large as forest itself. For example, plants provide food and oxygen needed by animals. And their waste products are recycled in the soil to be used by new plants as they grow.

Ecology

Ecology is the study of animals and plants in their natural environment. Ecologists try to find out why animals and plants live in some places but not in others. They also study the conditions needed for survival.

Most organisms are well-adapted to the place they live - their habitat - and to their relationships with other plants and animals. But, outside interference may effect this. Many of the world's natural ecosystem have taken thousands of years to reach a balanced state. If the climate does not change suddenly, an ecosystem can stay balanced for thousands of years to come. But humans often upset these balanced environments.

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CLIMATE ZONES

Climate shapes our planet and determines the landscape, vegetation, and wildlife of each region. There are NINE climate zones in this world. They are: Polar, Subpolar, Temperate, Subtropical, Desert, Tropical, Equatorial, Subpolar, and Mediterranean.

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RAIN FORESTS

Rain forests are the world's riches biomes. (Biome is a large community of plants and animals that occupies a particular region). These forest grow mainly near the equator. Rich in wildlife, they are under threat from human. There are more species of plants and animals in rain forest than any other biome on earth. The largest rain forests are the tropical forests of South America, Africa, Southeast Asia. The tropical climate is always warm and wet, with no winter, and plants grow all year long. The result is thick growth of trees, ferns, vines, and other plants. These in turn, support an extraordinarily rich variety of animal life, especially insects and birds.

Plants grow rapidly in a rain forest, and to reach the sunlight, the trees grow very tall. The rain forest has three distinct layers: the forest floor, the understory, and the canopy. Most of the trees have shallow roots, and get their nutrients from the upper layers of soil. Many support themselves with roots that grow outward, acting like props or buttresses. Smaller trees, seedlings, and shrubs form the lower layers nearer to the ground.

The main canopy is usually between 100 and 164 feet above the ground, where the slender trunks break into a cluster of branches. The tallest trees reach even higher - around 197 feet.

Rich habitat

Although they cover only six percent of the earth's surface, tropical rain forests contain about three fourths of all known species of animals and plants. There are plants in flower or fruit producing everywhere and every time of the year. They produce constant food supply for birds, bats, insects, snakes, and other animals.

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