Recently I engaged in a discussion on Facebook about the indigenous people of America. A couple of my friends I went to high school and college with suggested that the indigenous people were of African descent. Mainly because Africa is the cradle of humanity and the first people to arrive here had to be of African descent. They pointed to DNA evidence and yada yada yada posting links to articles citing DNA correlation between skulls found in Mexico to and America.
There's always room for discussion but perhaps the question Did Africans reach the Americas and found the Olmec civilization, as outlined in They Came Before Columbus? by /u/CommodoreCoCo will answer your inquiry.