Restriction enzyme digestion — cutting DNA at known recognition sequences and separating the resulting fragments by size, which produces a pattern that can indicate whether human DNA is present but cannot sequence it or provide detailed population information.

Southern blotting — a technique for detecting specific DNA sequences by transferring them to a membrane and probing with labeled complementary sequences.

What was not yet available in practical form was polymerase chain reaction — PCR — the technique that made it possible to amplify tiny quantities of surviving ancient DNA into amounts large enough for detailed sequencing analysis.

PCR was developed at Cetus Corporation in 1983 and 1984, its first published descriptions appeared in 1985 and 1986, and it took several years for the technique to become widely available and for researchers to understand how to apply it to ancient DNA samples with appropriate contamination controls.

The ancient DNA revolution that transformed paleoanthropology and archaeology — producing readable genomes from Neanderthals, from ancient Native Americans like the Anzick Child and the Spirit Cave mummy, from populations across the globe — came after 1986.