Standards needed to record the mark of our ancestors

Jackson Njau, a co-director of field research at palaeontological sites in eastern Africa’s Olduvai Gorge, has written in the journal Science of the lack of agreement on interpreting marks on fossil bones and if they were made by stone tools or by biting animals.  This is leading to uncertainty over when exactly early hominids began using tools to kill and butcher animals — a fundamental step in human evolution.

“There’s really no solid, standard method of analysing these bones that is used by all researchers,” he said. “And there is no universal guide, nothing that is part of one’s training as a student, that tells you reliably how to judge one type of mark from another.”

A close-up of a fossilized zebra bone shows a variety of cuts and grooves, suggesting the difficulty of distinguishing marks made by stone tools from those made by animals. Image: Courtesy of Indiana University.

A standard approach

His Science Perspectives article, published in the April 6 2012  issue and entitled “Reading Pliocene Bones,” contends that the “way forward” is through further experimentation, integration of different disciplines to better understand the fossil record, and blind testing of bone samples by researchers and students.

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