It does not depend on the researcher’s judgment about which skulls look similar to which other skulls.

It is a chemical record that can be read with methods that do not require subjective comparison.

When that record shows haplogroup D1 in a girl who died in the Yucatán twelve thousand years ago, the finding is not filtered through the interpretive ambiguities that have made craniometrics such a contested field.

This is one reason why the ancient genomic revolution has been so transformative for the study of early Americans specifically.

The questions that had been generating inconclusive debate in physical anthropology for decades — questions about the number of founding migrations, the relationship between early and later American populations, the geographic origins of different population groups — are the exact questions that ancient DNA is well-positioned to address.