Indigenous<span> cultures shaped, and were shaped by, the </span>geography<span> of North America. The first North Americans are believed to have </span>migrate<span>d from Siberia, in northeast Asia, by crossing a </span>land bridge<span> over the Bering Strait. These populations fanned out southward, to present-day Florida, California, Mexico, and Central America. </span>
<span>The Olmec and the Maya, indigenous to Central America, built the first cities on the continent, eventually leading to the great urban areas of Tenochtitlan, Texcoco, and Tlacopan. These cities, in what is now central Mexico, boasted </span>sophisticated engineering<span> structures, such as </span>canal<span>s, apartment buildings, and </span>irrigation<span> systems. </span>
<span>Many of these early North American cultures were scientifically and agriculturally advanced. Mayan calendars and </span>almanac<span>s recorded </span>celestial<span>events such as </span>eclipse<span>s and </span>seasonal<span> changes. The Mayans were also mathematically advanced. Their counting system was able to represent very large numbers using only three symbols: dots, lines, and a football-shaped symbol that indicated a zero. The Mayans were, in fact, the first culture to have a written symbol for zero. </span>
<span>Cultures throughout southern North America harvested corn, squash, and beans in regular cycles. This sort of </span>agriculture<span> allowed major </span>civilization<span>s to develop. People were no longer bound to produce food and shelter for their families—some people could work in the food and construction industries while others became engineers, artists, and political leaders. Leading North American civilizations include the Maya and Aztec, in what is now Mexico, and the Iroquois, native to southeastern Canada and the northeastern United States. .................</span>
Answer:
the U.S. Commission on Civil Rights
