large area

straight rows

different types

healthful foods

delayed

forbidden

started

watched

enemies

kinds

likes

sizes

cold water

golden rocks

small amounts

valuable items

Everyone should study to become an ecologist.

It is important to protect all of earth's ecosystems.

The destruction of the ozone layer is an ecological disaster.

The destruction of the rain forests is an ecological disaster.

because ecology is a delicate subject that some people don't approve of

because people can use tools such as a balance to weigh harmful substances

because there are obvious heroes and villains when it comes to protecting the earth

because making decisions about natural resources often involves difficult decisions

The rain forest is an important habitat for animals.

The rain forest is a major source of Earth's oxygen.

Rain forest plants are a source of important medicines.

Rain forest plants are a major source of Earth's food supply.

air

ecologist

forest

mammal

"Put trash in its place."

"Now, these forests are gone."

"Trees give us resources and natural beauty."

"The sea covers four-fifths of Earth's surface."