Tests on the sand they were buried in, using two different dating techniques (thermoluminescence and oxygen-isotope analysis), suggest they are between 70, 000 and 80, 000 years old.

ECONOMIST: A cave in South Africa may rewrite human history

Vatsaloo brought that about, too, by sketching out modern designs based on the natural forms of the countryside, and with Srithap painstakingly devising a way to render them by combining two traditional techniques.

FORBES: Weaving Connections

Professor Robin Lovell-Badge, of the Medical Research Council's National Institute For Medical Research, said the work was exciting, but work was required to end the reliance on viruses, and to tease out why two different techniques produced similar results.

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Two innovative techniques for gathering samples were revealed at the Interscience Conference on Anti-Microbial Agents and Chemotherapy in Toronto, Canada, and reported on the New Scientist website.

BBC: pipette and samples