How did the spread of civilization begin in the americas

Explanation:

Earlier American civilisation were possible because they came to the continent passing the Bering Strait. Historians don't know exactly how they passed, but they assure that.

That's why earlier native settle in North America, and after a certain time, they were establishing new settlements around all continent, central and south america. This is one explanation about why native people are alike in all continent, some tradition have points in common, like animalistic religions and believes.

they required less loading and unloading

explanation:

the shipping container improved shipping because it cut down on unloading time by three weeks, eliminated wasted space, and allowed ships to carry.

d. she conquered the black sea coast and parts of poland.