Whether it was a family day out at the beach, complete with prehistoric equivalent of a bucket and spade, we’ll never know, but one thing is for sure: about 13,000 years ago a little band of humans were pottering about on a shore in western Canada.
Researchers have unearthed 29 footprints in a layer of sediment on the shoreline of Calvert Island in British Columbia. Between 11,000 and 14,000 years ago, as the world was coming towards the end of the last ice age, the sea level there was 2m to 3m lower than today.
While it is not clear quite how many humans were responsible for the tracks, the team said there are at least three different sizes of footprints, including one set that appeared to belong to a child.
“We were actively searching for archaeological sites along this lower shoreline when we came across the footprints. It is likely the tracks were left in an area that was just above the high tide line 13,000 years ago,” said Dr Duncan McLaren, first author of the research from the University of Victoria in British Columbia and the Hakai Institute on Calvert Island.
Writing in the journal Plos One, the team describe how they began excavations on the island in 2014, noting that nearby there were shell-containing man-made rubbish dumps, or middens, which dated to up to 6,100 years ago, as well as chipped stone tools and manmade arrangements of stone boulders on the seashore.
“This site has a large, protected beach, which we felt was likely to have attracted people to it for many millennia. As sea level has been relatively stable in the region over the last 14,000 years, we reasoned that this area had potential for very old archaeological remains,” said McLaren.
The first human footprint was unearthed 60cm below the surface of the current beach, pressed into a layer of brown clay and filled with black sand and gravel. Fortunately, small pieces of wood were discovered in the heel of the print, and were radiocarbon-dated to just over 13,000 years ago.
The team returned during 2015 and 2016 to carry out further excavations, uncovering another 28 footprints. In some cases it was possible to see the impressions of individual toes and arches of the feet. Measurements of 18 of the tracks revealed they were made by at least three different individuals. “We had to excavate very carefully and slowly, which was difficult as we had to race the tide,” said McLaren.
McLaren said the finds helped to unpick a longstanding conundrum. In the last ice age, Siberia and Alaska were connected by a large land bridge in an area known as Beringia, while Canada was covered in ice sheets.“The basic question that many archaeologists ask is: ‘How did people get from Beringia to the area south of Canada during the last ice age?’” said McLaren.
The new research adds weight to the idea that humans moved along glacier-free areas of land along the coast, between the ice and the sea – areas known to have provided a refuge for various plants and animals. “It suggests that people were using watercraft, and thriving and exploring coastal areas very early on,” McLaren said.
Prof Nick Ashton, curator of Palaeolithic and Mesolithic collections at the British Museum, who has worked on the ancient Happisburgh hominid footprints in Norfolk, welcomed the findings. “This is an important discovery that has implications for the earliest colonisation of America,” he said.
“It supports the idea that the first peopling of the Americas was from eastern Asia at a time of lower sea levels, when the landmasses were larger, but probably with the assistance of sea-faring vessels. The footprints provide a very tangible link to the first Americans.”
