The two lines of evidence — human mitochondrial DNA and human-consistent fecal biomarkers — pointed to the same conclusion through independent routes.

This convergence is exactly the kind of evidence that is most compelling in science.

When two independent methods, using different types of data and different analytical techniques, produce results consistent with the same interpretation, the probability that both are artifacts of error or contamination decreases substantially.

It is possible to imagine how contamination or other problems could produce a false positive in DNA analysis alone.

It is possible to imagine how a coprolite misidentification could produce a false positive in DNA analysis.