Not perfectly, and not completely, but more directly than any previous method.

The Halocline And The Preserved Past

The specific chemistry of the water in the Yucatán cave system is worth understanding in some detail, because it is central to why Naia’s bones were preserved in a way that allowed the DNA analysis to succeed.

The halocline — the boundary layer between fresh water and salt water that exists within the flooded Yucatán caves — is chemically complex.

Above it, fresh water from the surface percolates through the limestone and accumulates.