Ancient Footprints in New Mexico may place Human Migration into the Americas back to the Ice Ages

Footprints of ancient humans were uncovered in a trench in White Sands National Park in New Mexico. Carbon dating using seeds of ancient plants surrounding the prints date them to about 23,000 years ago. That implies humans occupied the Americas about 8000 years earlier then what most archeologists believed. While these results are controversial, they are the first significant piece of evidence for building a case that could completely change our understanding of human history.

In 2009, David Bustos, the resource program manager of the park, discovered the footprints for the first time. Since then, Bustos along with several teams of scientists and archeologists have uncovered thousands of prints across the park. The prints are thought to have been formed by ancient people walking along lakes, their feet imprinting the ground. Sediment would fill these holes and as the ground hardened, the prints would remain in tack, lost under layers of white sand. However, erosion has uncovered these prints.

Distinctly human footprints found at the White Sands National Park in New Mexico

Some of these prints are highly visible, while others can only be made out when the ground is wet. However, we know that these prints belonged to ancient humans. Analysis of the prints using ground-penetrating radar have revealed the presence of heels and toes. These human prints are scattered between other animal prints including ancient mammals, and camels. Once scientists knew that the prints belonged to people, the next reasonable question was to determine their age.

Scientists observed that there were many preserved ditch grass seeds along with the footprints. Using radio carbon-dating, they realized that the seeds dated back to around the end of the last ice age some 22,000 years ago. This motivated a more comprehensive study where scientists dug a trench near a cluster of human and animal footprints to create a cross-section in the earth. Then they collected seed beds in the layers surrounding the prints and measured the carbon found inside. They determined that the oldest prints were located below a seed bed carbon dated to 22,800 years ago.

While the methods used in the current study are scientifically valid,  archeologists are not quick to jump to conclusions. Some archaeologists want stronger data before they accept the findings. In addition, alternate explanations of the phenomenon must be discussed and accounted for in future studies. For example, the seeds may not be as old as they appear: it’s possible that they absorbed carbon from old lake water. Regardless, this study provides some of the best evidence that people travelled to the Americas before 16,000 years ago.