Story of human origins evolves

James Cook University researchers have raised new theories that could rewrite the story of human evolution.

The Head of JCU’s School of Earth and Environmental Sciences, Professor Paul Dirks, will discuss the findings at a free public lecture entitled, ‘The origins of humans: the discovery and dating of sediba’, in Cairns on Thursday April 26.

Professor Dirks co-founded the AfricaArray program, which investigates the structure and tectonics of the African plate from the Earth’s surface to the core-mantle boundary. It was through this program that he became involved in the discovery of new hominid fossil deposits.

“Both myself and Lee Berger, from the University of Witwatersrand in South Africa, realised there was a lack of input from geologists in looking for hominid fossils, so we came up with a project to explore for fossil sites in the Cradle of Humankind World Heritage Site and understand their distribution in the landscape,” he said.

“We didn’t set out to discover new hominid fossils – but that’s what happened.”

In 2008 Professor Berger and his son found the partial remains of two ancient human-like creatures – an adult female and a 10-year-old boy from almost two million years ago.

Professor Dirks said the creatures – assigned the name Australopithecus sediba – filled an important gap between older hominids and the group of more modern species known as Homo, which includes our own kind.

“It's at the point of transition from an ape that walks on two legs to, effectively, us,” he said.

“I was directly involved in the discovery and consequently took on the role of describing the geological setting and determining the age of the remains. The geological studies demonstrate the dynamic nature of the landscape in which sediba lived and died.”

The studies have led to Professor Dirks, with his colleagues at JCU Townsville and co-workers in the USA and Africa, suggesting that the Great Rift Valley of East Africa – the birthplace of the human species – may have taken longer to develop than previously believed.

Professor Dirks’ presentation is the latest in James Cook University’s annual series of public lectures in science and engineering. The free lecture will be held in the Crowther Theatre at James Cook University in Smithfield on Thursday April 26. Refreshments will be served from 5.30pm and the lecture will begin at 6pm.

Issued April 14, 2012

Media enquiries: linden.woodward@jcu.edu.au