In the late sixteenth century, Europeans began journeying to the region in North America that became the original thirteen colonies. Many explorers reported on the features of the land and the customs of native peoples. But their primary goal was to find a more direct sea route to Asia or acquire instant wealth from discovering precious metals. Then the English founded permanent settlements along the Atlantic coast. From that time on, North America was like a scientific laboratory, helping scientists test ancient theories about the size and shape of the Earth or the location of oceans. Mountains, rivers, lakes, and bays invited closer investigation. Soon ordinary colonizers and settlers became geographers, naturalists, and mapmakers as they ventured into the wilderness. Spanish naturalists (those who study plant and animal life) explored the American Southwest from their base of New Spain (now Mexico). In 1590 the Spaniard...