Hunter-gatherers from Asia migrated to North America over a land bridge between Siberia and Alaska during the last Ice Age approximately 30,000 years ago. As the climate warmed, sea levels rose and the land bridge disappeared. Native Americans adapted to different environments across North America by developing diverse cultures and ways of life to make use of local natural resources for food, clothing, and shelter. Though cultural practices varied regionally, most Native American societies shared some common beliefs like respecting nature, not owning land, and only using necessary resources.