Despite their homelands being situated among the harshest, most inhospitable climes on Earth, with year round temperatures frequently near or below freezing and constant powerful circumpolar winds from the 'furious fifties,' they were able to tolerate such extreme conditions despite their traditional attire consisting of little more than a loincloth and an occasional loosely draped shawl. They frequently went without protection on their upper body and lower extremities altogether. Darwin describes a vivid scene where a Fuegian mother is standing in a shallow boat that approaches the Beagle in order to conduct raid. She's wearing nothing but newborn nursing at her breast, and she and her child both seem indifferent to the the snowfall and freezing rain melting on their skin.
They did not use permanent dwellings, and basically lived as gatherers using simple temporary makeshift huts with one side facing the wind and the other side open, and of course a fire, which gave the region its name. But it was not uncommon for them to spend days foraging for mussels, drenched in the frigid crashing breakers of the Southern Ocean.
This is 30 years before he published the Origin of Species and long before he had developed an articulated concept of natural selection, but The experience did inspire him to remark how it made intuitive sense that as the population of mankind spread across the Earth, that it would have differentiated and adapted to different climates in accordance with whatever underlying principles had driven the same process he had observed this happening with other species.
If curious, Google around for Jemmy Button and York Minster, these being too individuals who had been kidnapped from Tierra del Fuego and taken to England on a prior Beagle expedition, and returned on the one accompanied by Darwin.
You should pick up Kon-Tiki - those guys discovered a lot about ancient boating.
(Probably a species of rhino inhabitant swamps could swim among close islands. Elephants are surprisingly good swimmers so, why not rhinos?)
I laughed out loudly at the office when I read this. My coworker is wondering if I'm bonkers.
On a more serious note, the orthodox time line of human existence needs revision. There is too much contradictory evidence: oral accounts, human footprints beside dinosaur foot impressions, Gobeki-Tepli and other structures, prehistoric sculpture like lion-man and vogelherd, now this.
IMHO concern that the population wasn't large enough for multiple people to attempt the trick ignore the timescales involved. These events could span tens of thousands of years--longer than all of recorded history.
I think if you throw enough hominins in small boats at the ocean, at least a few of them are bound to survive the trip, right? I wonder how many island settlers in pre-history were just castaways who happened to hold on to a tree long enough to survive a monsoon-spurred ocean trip.