Around 26,000 years ago, the ice sheets comprising the Earth's arctic regions reached their maximum extension, reaching as far south as Germany. This period is appropriately known as the Last Glacial Maximum, and it occurred at around the same time early humans were beginning to explore the arctic regions. Our picture of early human movement in the arctic region before the Last Glacial Maximum is hazy at best—strikingly little evidence exists to indicate our ancestors were ever there.
A handful of discoveries in the last two decades have shown that contrary to popular belief, humans were in fact present in the arctic prior to the Last Glacial Maximum. There were some artifacts found at the Arctic Circle dating to 40,000 years and some traces of human activity a bit further north which dated to 28,000 years ago, but outside of this meager evidence, archaeologists had little else to go on to indicate how early the first humans had actually arrived in the Arctic and how far north they had traveled. Recently, a team led by archaeologists from the Russian Academy of Sciences discovered a 45,000 year old woolly mammoth carcass which bears the telltale marks of death by humans, suggesting that our ancestors could have arrived far north of the Arctic Circle about 15,000 years earlier than previously thought.
As the team details in an article published Friday in Science, a woolly mammoth carcass unearthed in 2012 at nearly 72°N latitude (well north of the Arctic Circle, which begins at approximately 66°N) had slice marks on its tusks and bones which were similar to those seen on mammoth bones at a younger Siberian site which was a known mammoth hunting ground. According to the team, the nature of these injuries makes it clear that the mammoth died by human hands.
With the exception of 45,000 year old human remains which were recently found at 57°N in Siberia, human remains which predate the Last Glacial Maximum by more than about 3000 years haven't been found north of 55°N. That's part of what makes this discovery such a big deal. The bones and artifacts found at the Yana River site in Siberia were about the same latitude as this most recent discovery, although these artifacts are about 15,000 years younger.
Previously, archaeologists assumed that most of our ancestors were hanging out at 55°N or further south around 40,000 years ago because they hadn't yet figured out how to deal with the hostile arctic environment. Yet the cuts on this woolly mammoth carcass suggest that they had actually been capable of hunting up to 1,700 kilometers north of these 55°N remains, a feat achieved about 15,000 years earlier than previously assumed.
"Humans' ability to survive in the Arctic environment, and their spread within the region as early as [45,000 years ago], represents an important cultural and adaptational shift," the team concludes. "We speculate that adaptation changes that ensured human survival there may be related to innovations in mammoth hunting. This is a rare case of unequivocal evidence for clear human involvement, even if there is no artifact association."