This drawing shows priests carrying the sacred Ark of the Covenant while the walls of Jericho fall. The Bible tells the story of a great battle in which Joshua, a leader of the Jews, made his...
The birth of the sea
The sea may have been formed by tremendous rains. Or, it may have been formed by steam from inside the earth. Scientists think the earth was formed more than four and one-half billion years ago....
People who study plants
Do you ever wonder about plants, and how they live and grow? Have you ever taken a flower apart to see what was inside it? If you have wondered about, or done these things, maybe someday you'll be a...
The air makers
Most scientists think that the first tiny sea plants made it possible for life to come onto the land. To live, plants and animals must take in a gas called oxygen. The tiny sea plants and animals of...
Plants of Long Ago
The plants that grew on earth hundreds of millions of years ago didn't look much like the plants we see around us today. Scientists have learned a great deal about what the world was like long ago....
Getting help from animals
Scientists study animals. > A veterinarian treats animals. Learning how to make animals well can help scientists learn how to keep people well. Some kinds of animals get the same kinds of diseases...
Learning about animals
Biologists, zoologists, and naturalists are scientists who study living things. They often work in laboratories or even in their own homes. But sometimes they go to wild parts of the world to study...
Elephants without trunks
Most scientists believe that 50 million years ago there were elephants living in swamps where Egypt is today. But they didn't look anything like elephants do now. The first elephants didn't have...
Horses without hoofs
> Eohippus > > \ Scientists say that if you could see the horses that lived 55 million years ago, you wouldn't know they were horses. They had toes on their feet instead of hoofs. They ate fruit...
Tyrannosaurus the meat-eater
One of the most fierce-looking dinosaurs was Tyrannosaurus. Scientists can tell from its sharp teeth that it was a meat-eater. But they're not sure how it got its food. Some scientists think...
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