In chapter one the author said that there were debates still going on

In chapter one the author said that there were debates still going on (about when and how humans first arrived in North America). Small hunting groups crossed in Alaska around this time. I wonder if the small hunting groups stopped to rest or kept going until they got to their designated area. The settlers were very skilled in hunting and gathering. Can this be proved? They even killed each other sometimes! Why? Was it for food? …. Some humans walked
while the others traveled by the boats. I thought that was elfish of them. Why not have all the
humans travel by boats. Ancient Indians adapted to their environments and as the days grew hotter, the animals became extinct. So basically since it was so hot, food and water was no longer there and that’s why the animals became extinct. They ( the Ancient Indians ) mastered the use of fire, technology, and religions. Native Americans transformed into farming society. Farming towns appeared in Mexico around 1500 B.C.E. The Mayas developed a rich written language.
What was the language? The Mexica began drifting southward from Northwest Mexico. Mexica were intensely spiritual. Native Americans did not worship a single god but believed in spirits. Native Americans had well defined social roads. Anasazi were best known of the Southwest pueblo cultures. The leaders and warriors worked as much as the rest of the people did. At least they were equal.