A tropical rain forest is a forest that is located in a region that is warm year round with tall trees. On average, between 50 to 260 inches of rain falls in a tropical rain forest each year.
Almost all rain forests are located near the equator. The average humidity in rain forests is between 77 and 88 percent and the temperature rarely rises above 93 degrees Fahrenheit. Most rain forests have a season where less rain falls, and some have a dry season.
Rain forests cover less than six percent of the earth's land area, but scientists estimate that more than 50 percent of the planet's animals and plants live in tropical rain forests. It is also thought that 40 percent of the earth's oxygen comes from rain forests. These rain forests are also home to more types of trees than any other place on earth. Trees account for 70 percent of all plants within the rain forest.
The trees within rain forests often do not grow branches until about 100 feet in the air. Branches lower on the tree are less likely to receive light, making it more important to grow branches higher up. Trees in rain forests also have bark that is thin and smooth because there is little danger the tree will face freezing temperatures or lose too much water.