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Meeting the Missing Link

Image of fossil skull

The cranium of the juvenile skeleton. Photo: Brett Eloff courtesy Wits University

By Paul Dirks

Paul Dirks gives a first-hand account of the expedition that found a new species of hominid linking humans and apes.

Professor Paul Dirks is Head of the School of Earth and Environmental Sciences at James Cook University, and former Head of the School of GeoSciences at Wits University in South Africa.

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As a structural geologist I never expected to become so closely involved in such an important fossil find as Australopithecus sediba, which may be the transitional species between ape-man and the genus Homo from which we evolved (see Linking Man and Ape, p.15).

Between 2002 and 2009 I was Head of the School of Geosciences in the University of the Witwatersrand, Johannesburg, and would regularly visit the fossil sites. Then, in early 2008, I decided to start a new project with my Wits University colleague, Professor Lee Berger, aimed at understanding the geological and geomorphological setting of the fossil-bearing cave systems.

I had been toying with the idea that if fossils occur in deposits along faults and rifts, which formed as a result of uplift of the high veld in response to processes deep inside the Earth, then human evolution itself may be somehow linked to those tectonic processes as well. If we know where the caves are, and we can predict how the landscape developed, then maybe we can predict where the caves with fossils are.

We intended to map a large section of the Cradle of Humankind World Heritage Site, and were hoping that this would give us some fundamental insights into the story of human evolution and help us understand the relationships between the caves and the landscape better.

Using air photos, satellite images, and...

The full text of this article can be purchased from Informit.