They did it by setting anti slavery activist to put slavery to an end.

The three staples of Native American food are corn, squash, and beans. Other foods that have been used widely in Native American culture include greens, Deer meat, berries, pumpkin, squash, and wild rice.
The Native Americans are well revered for being resourceful people, and when it comes to Native American food, there is no difference. They were well versed at using the ingredients that were readily available to them and for making many different foods with them. Corn and various corn products are abundant in Native American food recipes and they have lent many of their earliest delicacies to the American culture as a whole.

Answer:
largely due to the existence of convenient land bridges and easy sea lanes passable in summer or winter, in dry or wet seasons.
Explanation: