Scientists don’t know who the first Americans were, where they came from, how they got here, or how long ago they came. All they have are educated guesses, many of which are being proven wrong in recent years. Here is another piece of evidence from a reliable source that shows how little we know about the prehistory of the Americas. From the article:
The stormy scientific debate over the origins of the first Americans has taken a surprising geographic turn. Human skulls unearthed in Brazil and ranging in age from about 8,000 to 11,000 years look more like modern Africans and Australian aborigines than like modern Asians or Native Americans, according to a report presented in Kansas City at last week’s annual meeting of the American Association of Physical Anthropologists.This finding contradicts the influential theory that Asians were the first to cross the now submerged Bering land bridge to North America around 12,000 years ago, says Walter A. Neves of the University of Sao Paulo. Instead, African migrants actually may have been the first to take this northern route into the Americas, theorizes Neves, who directed the Brazilian excavation and fossil analysis. At least 45,000 years ago, he adds, migrating Africans reached Australia via a southern route.(emphasis added)
Notice how tentative the language is? That is good science. It means that we don’t know for sure even with the availability of recent scientific advances such as linguistics and DNA research.
The enormous gaps in what we do know for sure about American prehistory leaves plenty of room for multiple migrations and peoples about which we know nothing. That means that there is plenty of room for Jaredites, Nephites, Mulekites, and Lamanites.
Most real scientists will readily admit that what we do know is just a drop in the ocean of what remains unknown. Notwithstanding all that mankind has learned, we are still largely ignorant of the universe around us, and that is true for all of us, not just religious people.