Footprints left behind in layers of clay and silt at New Mexico’s White Sands Nationwide Park could also be between 23,000 and 21,000 years previous. That’s based mostly on radiocarbon relationship of the stays of grass seeds buried within the layers of sediment above and under the tracks. If the dates are appropriate, the tracks are proof that individuals walked beside the now-dry Lake Otero through the top of the final ice age, when kilometers of ice lined the northern half of the continent. And that may imply that individuals should have arrived in North America—and made their strategy to an space properly south of the ice—earlier than the ice sheets expanded sufficient to shut off the route.
Arriving forward of the ice sheets
Bournemouth College archaeologist Matthew Bennett and his colleagues discovered a complete of 61 human footprints east of an space known as Alkali Flat, which was as soon as the mattress and shoreline of an historic lake. Over time, because the lake’s edge expanded and contracted with shifts in local weather, it left behind distinct layers of clay, silt, and sand. Seven of these layers, within the space Bennett and his colleagues lately excavated, held human tracks together with these of long-lost megafauna.
A number of the sediment layers contained the stays of historic grass seeds blended with the sediment. Bennett and his colleagues radiocarbon-dated seeds from the layer slightly below the oldest footprints and the layer simply above the latest ones. In response to the outcomes, the oldest footprints had been made someday after 23,000 years in the past; the latest ones had been made someday earlier than 21,000 years in the past. At the moment, the northern half of the continent was a number of kilometers under large sheets of ice.
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