Early man in America takes a step backward — Science News, January 27, 1973
“Early Americans lived among and hunted mammoth, camel, extinct horse and bison as far back as 15,000 years. Now there is mounting evidence for a second breakthrough that will push the history of man in America back to 30,000 years — and possibly further.”
The question of when humans first set foot in the Americas is still hotly debated. Recent fossil and archaeological evidence suggests the first inhabitants arrived tens of thousands of years ago. For instance, humanlike footprints in New Mexico date to about 20,000 years ago (SN: 11/6/21, p. 12). And stone tools found in a cave hint that humans resided in Mexico roughly 30,000 years ago (SN: 7/3/21 & 7/17/21, p. 16). Some archaeologists argue that stones caked with mastodon bone residue that were found in California were tools used by humans or their close relatives around 130,000 years ago, although that claim remains controversial (SN Online: 12/4/20). Pinning down the timeline of human settlement could reveal how people spread across North and South America.
2023-02-03 07:58:40
Source from www.sciencenews.org
Fifty years ago in 1969, scientists began heavily debating when and how humans first set foot in North America. The main two theories at the time were the land bridge theory and coastal migration theory. Through research, a reasonable amount of consensus has been reached on this long-debated topic.
The consensus today is that humans first populated the island of Beringia about 20,000 years ago. The land bridge theory proposes a foot path between Asia and North America being created due to the drastic decrease in sea levels during the last Ice Age. This allowed early humans to cross the land bridge and come to North America. The coastal migration theory states that humans traveled from Asia to North America by sea, rather than over land.
Recent evidence has suggested that the land bridge theory and coastal migration theory were more intertwined than previously thought. Instead of solely relying on one theory, this new research showed that both forms of transportation were used to cross over. The first wave of migrants would have relied on the land bridge and the second wave would have moved along the coast of North America by boat.
Looking back 50 years, it is remarkable to see how much research has been done, resulting in a much clearer picture of the settlement of North America. Going forward, more evidence will continue to accumulate, allowing us to learn even more about the history of human settlement in the Americas.