New research published today in nature from an international research group – including researchers from the La Trobe University Department…
New research published today in nature from an international research group – including researchers from the La Trobe University Department of Archeology and History and the University of Melbournes Agricultural College – is the first to provide a comprehensive early human development timeline for the Humanist Cradle of South Africa.
Headed by the University of Cape Town, research also investigates the climate conditions of our earliest ancestors in the area.
So far, the lack of computer technicians for rock fossils made it difficult for researchers to understand the relationship between East and South Africa hominin species. In addition, the South African post has often been considered unthinkable compared to East Africa where volcanic ash layers enable high resolution updates.
Professor Andy Herries, who conducted research and excavations at many of the dated sites noted that “while the South African disc was the first to show Africa as a starting point for people, the complexity of the cave and the difficulty of dating them has meant that the South African post has has been difficult to interpret. “
” In this study, we show that flow stones in the caves can act almost like the volcanic layers of East Africa, which form in different caves at the same time, so that we can directly relate their sequences and fossils to a regional
Professor Jon Woodhead of the University of Melbourne said the research findings show that
“The Cradle caves dated to only six specific periods of time between about 3.2 and 1
.3 million years ago,”  Researcher from University of Cape Town, Dr Robyn Pickering, said: “Unlike previous dating work, which often focused on p a cave, sometimes with just one chamber of the cave, we provide direct ages of eight caves and a model to explain the age of all the fossils from all over the region.
“Now we can link the findings from separate caves and create a better picture of evolutionary history in southern Africa.”
Humanity’s Rock is a World Heritage Site consists of complex fossil-bearing caves. It is the world’s richest early hominin place and is home to nearly 40 percent of all known human ancestor fossils, including the famous Australopithecus africanus skull named Mrs Ples.
With the help of state-of-the-art uranium conductors developed at the University of Melbourne, researchers analyzed 28 flow stone layers found between fossil rich sediments in eight caves over the cradle. The results revealed that the fossils in these caves dated to six narrow time windows between 3.2 and 1.3 million years ago.
“The flow rods are the key,” said Dr Pickering.
“We know that significant flow points only grow in caves during wet periods when there is more rain outside the caves. By judging the flow stones, we pick these times out of precipitation. We know that in the meantime, when the caves were open , the climate was drier and more like what we are currently experiencing. “
This means that the early hominins living in the cradle experienced major changes in the local climate, from the warmer to the drier conditions, at least six times between 3 and 1 million years ago . However, the human fossils are preserved only during the drier periods preserved in the caves, which shifts the record of early human development.
This new paper, financed by Dr Pickers and Prof. Herries ARC DECRA and Future fellowships, is the result of over a decade of work and brings together a team of 10 researchers from Australia, South Africa and the United States. The majority of the dating analysis was done at the University of Melbourne, which is still the world leader in this type of data analysis. These results return the cradle to the forefront and open up new opportunities for researchers to answer complex questions about human history in the region.
“Robyn and her team have made an important contribution to our understanding of human development,” says senior paleoanthropologist Professor Bernard Wood, from the Center for Advanced Study of Human Paleobiology at George Washington University, USA, who is not a writer of the study .
“This is the most important advance to be made after the fossils themselves were discovered. The date of fossils is very important. The value of South African evidence has increased many times through this exemplary study of its temporary and deposition context.”