The new research of an international team of scientists led by the geochemist isotope of Cape Town University, Dr Robyn Pickering, is the first to provide time for the fossils of the caverns within the Cradle of Humanity. It also raises light on the climatic conditions of our earliest ancestors in the area.
Published online in the magazine Nature On November 21, 2018, the work corrects assumptions that the fossil caves of the region could never be related to each other. In fact, the research suggests fossils from Cradle Caves until only six specific times.
"Unlike previous data that often focused on one cave, sometimes only one room in the cave, we provide direct edges for eight caverns and a model to explain the age of all fossils throughout the region," says Dr Robyn Prenanta.
"Now we can join the results of separate caves and create a better image of evolution in southern Africa."
The Cradle of Humanity is a Patrimony of Human People formed by complex fossil caves. It is the richest website of human beings, and at home to almost 40% of all well-known human fossils, including the famous Australopithecus africanus skull, called Mrs. Ples.
Using uranium plumbing, researchers analyzed 28 fluid layers, which were found shaken between a fossil-rich sediment in eight caves across the Cradle. The results revealed that the fossils in these caves date to six narrow windows between 3.2 and 1.3 million years.
"The stitches are the key," says Pickering. "We know that they can only grow in caverns during wet times, when there is rain outside the cave. In the caves, we capture these times of increased rain. So we know that during the times inside, when the caverns were opened , the climate was drier and more similar to what we are currently experiencing ".
This means that the early men living in the Gaddle experienced great changes in the local climate, from wetter to more dry conditions, at least six times between 3 and 1 million years. However, only the driest times are kept in the caves, shaking the record of early human development.
Until now, the lack of data methods for Cradle-fossils has made it difficult for scientists to understand the relationship between the East and South African menin species. Moreover, the South African record has often been considered unquestionable in comparison with East Africa where volcanic ash deposits allow high distinction.
Professor Andy Herries, co-author in the University of the Trobe study in Australia, notes that "while the South African record was the first to show Africa as an original point for humans, the complexity of the caverns and difficult to date them meant that South African record has been difficult to interpret. "
"In this study we show that the caverns of the caverns can act almost as the volcanoes of Eastern Africa, forming different caves at the same time, allowing us to directly relate their sequences and fossils into a regional sequence," he says.
Dr. Pickering began dating the Cradle Caves back in 2005 as part of her PhD research. This new publication is a result of 13 years of work and brings together a team of 10 scientists from South Africa, Australia and the United States. The results return the Cradle to the forefront and open new opportunities for scientists to respond to complex questions about human history in the region.
"Robyn and her team have made an important contribution to our understanding of human development," says Bernard Wood, Professor Bernard Wood of the Center for the Advanced Study of Human Paleobiology at the George Washington University in the United States, who is not the author of the study.
"This is the most important advantage when the fossils themselves have been discovered. The fossils of phenomena are much more. The value of the South African evidence has increased many times through this exemplary study of its temporal and depopulation context."
Materials provided by University of Cape Town. Note: Content can be edited for style and length.