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[Galapagos]

This was published in PLoS ONE around a year ago:
PLoS ONE: A Three-Stage Colonization Model for the Peopling of the Americas

We evaluate the process by which the Americas were originally colonized and propose a three-stage model that integrates current genetic, archaeological, geological, and paleoecological data. Specifically, we analyze mitochondrial and nuclear genetic data by using complementary coalescent models of demographic history and incorporating non-genetic data to enhance the anthropological relevance of the analysis.
[...]
These results support a model for the peopling of the New World in which Amerind ancestors diverged from the Asian gene pool prior to 40,000 years ago and experienced a gradual population expansion as they moved into Beringia. After a long period of little change in population size in greater Beringia, Amerinds rapidly expanded into the Americas ≈15,000 years ago either through an interior ice-free corridor or along the coast. This rapid colonization of the New World was achieved by a founder group with an effective population size of ≈1,000–5,400 individuals. Our model presents a detailed scenario for the timing and scale of the initial migration to the Americas, substantially refines the estimate of New World founders, and provides a unified theory for testing with future datasets and analytic methods.

According to a more recent study, it was two migrations that populated the America:
First Americans arrived as 2 separate migrations, according to new genetic evidence

The first people to arrive in America traveled as at least two separate groups to arrive in their new home at about the same time, according to new genetic evidence published online on January 8th in Current Biology, a Cell Press publication.

After the Last Glacial Maximum some 15,000 to 17,000 years ago, one group entered North America from Beringia following the ice-free Pacific coastline, while another traversed an open land corridor between two ice sheets to arrive directly into the region east of the Rocky Mountains. (Beringia is the landmass that connected northeast Siberia to Alaska during the last ice age.) Those first Americans later gave rise to almost all modern Native American groups of North, Central, and South America, with the important exceptions of the Na-Dene and the Eskimos-Aleuts of northern North America, the researchers said.

Also.... is anyone here familiar with the theory that native Americans were from Israel?