The First Americans, Part 3

But the western coast was not the only available route for early colonists. An ice-free corridor formed after 2 ice sheets that had met in the middle of the continent began to melt. At first, the meltwater formed vast lakes, but these eventually drained, leaving dry land. This corridor ran along the eastern flank of the Rockies, from Alaska to the lower 48 states. It was originally believed to have opened up 13,000 years ago, which fit the Clovis-First scenario, but ruled out it being available for earlier people.

A group of scientists decided to take another look at this corridor, using new methods of dating, and determined that the corridor formed at least 14,000 to 15,000 years ago, possibly more. What's more, the corridor in northern Alberta was at least 400 kilometers wide and no longer held any large lakes. Now, the corridor was scoured by retreating ice and pierced by cold winds, so it would have seemed a formidable place to early travelers. But hunter-gatherers from Beringia may have decided to explore it after watching flocks of waterfowl head south in the fall and return in the spring. Food would have been scarce, but the explorers could have hunted birds or larger game, such as mountain sheep, now believed to have grazed in the Yukon and northern British Columbia.

The travelers may have taken along dogs. Siberian hunters first domesticated wolves as long ago as 33,000 years. These would have made valuable hunting companions and pack animals. A 1994 study revealed that dogs carrying 13 kilograms (28.7 lbs) could travel as far as 27 kilometers a day, in the right conditions. If hunting failed, and starvation threatened, the migrants could have eaten some of their dogs. One scientist calculated the colonists could have reached the southern end of the corridor in only four months, traveling at 16 kilometers a day.

Back at Buttermilk Creek in Texas, the scientists are still studying the tiny, delicate tools created and left by the pre-Clovis people, and may have found new clues about the origins of the Clovis people. 2,500 years after the pre-Clovis people knapped blades and bifaces, Clovis hunters used similar techniques across North America to make massive, elongated blades, some reaching 21 cm (8.3 inches) or more in length. It is possible the Clovis people were descended from earlier migrants coming through Beringia.

 

https://www.scientificamerican.com/article/the-first-americans/#:~:text=For%20decades%20archaeologists%20thought%20the,thousands%20of%20years%20before%20that.

The First Americans, Part 2

The Clovis-First model says humans reached the Americas by trekking overland, but others propose the earliest travelers arrived by sea, paddling small boats along the coast, from East Asia to southern Beringia and down the western coast of the Americas. Scientists first began thinking about this route in the late 1970s, when they started examining geologic and pollen records to reconstruct ancient environments along Canada's western coast. Instead of the entire northwestern coast laying under thick ice, analyses of coastal bogs showed that a coniferous forest thrived on Washington's Olympic Peninsula 13,000 years ago, and that other green refuges dotted the coast. Early humans camping in these spots would have found plenty of shellfish, salmon, waterfowl and caribou or other land animals grazing in the larger spots.

In fact, it is now known that much of the British Columbian coast was ice free at least 16,000 years ago. Although they haven't found any preserved boats, they were known to humans at least 45,000 years ago when humans island-hopped from Asia to Australia. Still, finding campsites of these exploring mariners are hard to find. This is because as the ice sheets melted, the sea level rose, drowning ancient coastlines under meters of water. However, in March 2011, evidence of early seafarers was found on Santa Rosa Island, just off the southern California coast. Nearly 12,000 years ago, Paleo-American sailors crossed 10 kilometers of open water to Santa Rosa, which would have required a boat. Bird bones and charcoal found at the site were dated to 11,800 years ago.

These travelers had hunted Canada geese and cormorants as well as pinnipeds (seals and sea lions). They also left behind distinctive technology, more than 50 dainty stemmed points that may have been part of darts used for hunting. Their design seemed very unlike the long, furrowed and sturdy-looking Clovis spearpoints. Very similar stemmed points were found scattered around the northern rim of the Pacific Ocean. The earliest came from the Korean peninsula, Japan and the Russian Far East, and were dated to around 15,000 years ago. Stemmed points found in Oregon were dated at 14,000 years old, and 12,000-year-old points were found on the Channel Islands, in Baja California and along coastal South America.

Even so, explorers of this rich coastal world were unlikely to have raced southward. They may have moved just a kilometer or so a year. They were moving into unpopulated lands, and had to maintain connections with people behind them in order to have marriage partners available.

 

https://www.scientificamerican.com/article/the-first-americans/#:~:text=For%20decades%20archaeologists%20thought%20the,thousands%20of%20years%20before%20that.