UOW scientist dates earliest evidence for modern human behaviour
18 Oct 2007 | Bernie Goldie
Evidence of early members of our species (Homo sapiens) living on the coast in South Africa, harvesting food from the sea and using red pigments far earlier than previously documented – 164,000 years ago – is being reported in the latest issue of the journal Nature.
Dr Zenobia Jacobs, a Research Fellow at the University of Wollongong’s School of Earth and Environmental Sciences and GeoQuEST Research Centre, was responsible for dating of the archaeological deposits at Pinnacle Point, located on the southern Cape coast of South Africa.
Dr Jacobs is part of an international team of researchers from Australia, South Africa, Israel, England, Greece and the United States reporting their new findings in the Nature paper, “Early human use of marine resources and pigment in South Africa during the Middle Pleistocene”. The research team was led by Dr Curtis Marean (Arizona State University) and funded by a US$2.5 million grant from the US National Science Foundation’s “Human Origins: Moving in New Directions (HOMINID)” program.
Their findings show that humans had expanded their diet to include shellfish and other marine resources by 164,000 years ago in coastal South Africa, perhaps as a response to harsh environmental conditions then in existence. The research team says it is the earliest known observation of this behaviour, pushing back the previous benchmark by 40,000 years. These new findings move back the timeline for the evolution of modern human behaviour, and show that lifestyles focused on coastal habitats and resources may have been crucial to the evolution and survival of these early humans.
The researchers also report that diet expansion was accompanied by the early use of pigment, most likely for symbolic behaviour such as body ornamentation or rock art. Archaeologists view symbolic behaviour as one of the clues that modern language may have been present. Previous discoveries in other coastal caves in South Africa – also dated by Dr Jacobs – showed that symbolic behaviour occurred as early as 75,000 years ago, much earlier than the first evidence elsewhere in the world.
The new evidence doubles the known time-depth of symbolic behaviour. “Our results support a growing body of evidence for the simultaneous anatomical, genetic and behavioural origins of Homo sapiens between about 195,000 and 164,000 years ago in sub-Saharan Africa, and confirms that Africa was the cradle for human evolution, in all its different forms,” said Dr Jacobs. Thousands of individual sand-sized grains of quartz were analysed by Dr Jacobs to date the archaeological deposits, using a method known as optically stimulated luminescence (OSL). This technique dates the last time that grains of sand are exposed to light, and UOW is recognised internationally as a world leader in this field of science.
MEDIA PLEASE NOTE: Dr Zenobia Jacobs can be contacted by phone (02) 4221 3633, fax (02) 4221 4250, or e-mail zenobia@uow.edu.au She is available this morning 17 October) at 11am for interviews in Room G27 School of Earth and Environmental Sciences, Bldg 41, University of Wollongong.
IMAGES AVAILABLE: The Media Unit can provide high-resolution photos of the site in South Africa where Dr Curtis Marean and an international team of researchers report the earliest dated evidence for human use of shellfish and pigments. High-resolution photos of utilised pigments are also available.
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