The first Amerindians from 9-14,000 YBP were Australoids. All of Asia was Australoid until 9,000 YBP. North Asia transitioned away from Australoid at that time, but the transition out of Australoid happened much later in south.
For instance, the full transition did not occur until 2,200 YBP in Vietnam, and in all probability, Filipinos, Malays, Indonesians, Nicobar Islanders, Taiwanese aborigines, Montagnards, some Thai hill tribes, Nagas and probably others never fully transitioned over and hence are referred to as Paleomongoloids. The lack of full transition in the south is due to the Australoid-Mongoloid transition occurring so much later down there.
Whether Amerindians are a Paleo or Neo Mongoloids has never been completely answered. The Na Dene people in the Far North may be more Neo. There were still a few Australoid tribes at contact, and an Australoid tribe called the Pericua lasted for some time in Baja California. Whatever is left of the Yaghan and other Patagonian tribes may well be Australoids also.
However, the Eskimo or Inuit people are full Neomongoloids as are the peoples of Siberia.