''Twin'' Ice Age Infants Discovered in 11,500 Year Old Alaska Grave

A tenderly decorated grave discovered in Alaska holds the remains of two infants dating back 11,500 years, the youngest Ice Age humans yet found in the Western Hemisphere, archaeologists say.

Interred together inside an ancient residence, one child was about 12 weeks old at the time of death, the other, a late-term fetus the first known instance of a prenatal burial in the Americas.

Researchers say that the babies were memorialized with an array of goods that was, by Paleoindian standards, rather lavish.

The grave was ornamented with a coating of red ochre and a complement of hunting tools, including two large stone points and four long foreshafts fashioned out of carved elk antler.

The hunting tools, known as hafted bifaces, are the earliest examples of their kind found in North America.

Together, the remains and artifacts, all found within an Ice Age residence, provide unprecedented insights into the nature of life and the rituals of death among some of the continents earliest inhabitants, researchers say.

This mortuary treatment is the first of its kind in the New World no other Paleoindian burials share this feature, said Dr. Ben Potter of the University of Alaska Fairbanks, referring to the burials being found inside a residence.

Researchers excavate a double infant burial at the Upward Sun River site, Alaska. (Courtesy Ben A. Potter)

Potter and his team found the grave last year at a site known as Upward Sun River in central Alaska, while investigating a structure that appears to have been a seasonal fishing, hunting and foraging camp.

And they discovered the grave directly beneath a similarly grim feature that the team found in 2010: the cremated remains of a 3-year-old boy.

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Why one body was cremated while the other two were not is one of the many mysteries posed by the find, Potter said.

The discrepancy could relate to the ages of the dead, or to their sex, as the two infants appear to have been female, and possibly twins.

This is the first evidence of multiple individuals [buried] within a single feature with fundamentally different treatments, which may reflect situational factors, [such as] who was present or absent at each event, or the expectedness or unexpectedness of the deaths, or age-grade differences, he said.

However, the burials did not occur very far apart in time.

It is most likely that all three children are part of a single community that used this exact feature, Potter said of the structure.

Since this appears to be a summer residential base camp, it is plausible that both burial events occurred during the same summer or during subsequent summers, he said.

The stratigraphy, or layering of soils, around the remains is the clearest indicator of this, suggesting a rather rapid series of somber events, Potter explained.

The infants were buried first, their grave having been dug under the camps main cooking hearth. They were then covered with the hearths original contents soil, charcoal, and animal bones, mostly fragments from salmon and ground squirrels.

But with the subsequent death of the toddler, anywhere from a few weeks to a full year later, the boys remains were cremated in the hearth itself, and the site was abandoned