A study of the oldest known sample of human DNA in the Americas suggests that humans arrived in the New World relatively recently, around 15,000 years ago.
The DNA was extracted from a 10,300-year-old tooth found in a cave on Prince of Wales Island off southern Alaska in 1996.
The sample represents a previously unknown lineage for the people who first arrived in the Americas.
Not sure about the contention about how transferable maritime skills are compared to purely terrestrial ones. There seems to be an awful lot of difference between the northwest coastal environment and that in California, for example.