Discovering Our Distant Ancestors
From the analysis of two hominid skulls and some bones near the Omo River in Ethiopia we know that Homo sapiens, anatomically modern man, evolved in Africa at least 195,000 years ago. So, as Chris Stringer points out in his book Lone Survivors: How We Came to Be the Only Humans on Earth, it would be logical to look first in Africa for evidence of the evolution of modern H. sapiens’ behavior.
Meticulous excavations have been regularly carried out since 1997 at the Blombos Caves at the southernmost coast of Africa. Findings there uncovered what might be called “the first human workshop,” revealing a surprising level of collaboration early in our evolution.
As Christopher Henshilwood, from the Universities of Bergen & Witwatersrand, says, the Blombos site “Documents the first known instance for the deliberate planning, production and storage of a pigmented compound and for the use of a container. This discovery serves as a benchmark during the early evolution of the cognitive abilities of Homo sapiens in Southern Africa.”
Ochre sites have been found dating to 200,000 years ago but, as Stringer points out, the preparation of red ochre in the form found at Blombos is a multi-step process involving a recipe for mixing the ingredients, then applying significant heat, and then storing the product. Three types of ochre were produced probably for painting, and toolkits appear to have been used more than once. Our ancestors collected, stored and worked with this soft clay, which is rich in iron oxide, and may well have had multiple uses, perhaps as a medicine, a coloring agent or sunscreen, or a kind of binder.
It is likely that the knowledge of this preparation was transmitted from generation to generation. Ochre was frequently used in early sites beyond the African continent by Paleolithic humans, including Neanderthals, as a pigment to mark their bodies for decoration and for designating social hierarchy, rites of passage, and other indications of cultural significance.
Artifacts at Blombos date from 100,000 to 75,000 years ago. Some of these and the markings found on the tools and cave walls could well be entirely aesthetic. Although H. erectus’ shell tools were found which have geometric engravings dating to around 500,000, this site shows that the use of more complex abstract symbols, of increased social organization, and of an unprecedented degree of environmental adaptation occurred as early as 100,000 years ago. It pushes back the dates for sophisticated cognitive actions such as flint working, ritual behaviors and personal decoration by more than 50,000 years before the cave paintings of Upper Paleolithic Europe.
Evidence of similar cognitive abilities has been found at other sites on the south African coast, such as at Pinnacle Point. Seashells apparently drilled for use as jewelry, requiring skills previously associated with the technology of the Cro-Magnons, have also been found in the region. Stringer feels that although the sophistication of the art and artifacts from Cro-Magnon Europe remains unprecedented, its foundation may have been similar to what underlay the Industrial Revolution or the Renaissance, in which the gradual and uneven accumulation of cognitive developments led finally to a cultural turning point.
Similarly, it would be wrong to imagine that the “Stone Age” was a single unchanging episode of our human history. It lasted hundreds of times longer than all of recorded history. Stringer suggests that across this vast space and time, a sort of multiregional interbreeding resulted in the rise of H. sapiens.
This evolution occurred all across Africa before the founding group of moderns departed. There are new findings that may place very early H. sapiens in ancient Morocco. Evidence is accumulating that its southern coast may have been the refuge where H. sapiens survived the expansion of the ice that covered most of northern Europe and that produced a population bottleneck seen in the record of our DNA.
New DNA research hints at contributions to our genome from previously unknown sources, possibly humans who came back to Africa in the long period after the first archaic dispersal. Taken all together, as Stringer points out, the origin of modern humans is much more complex than previously envisioned, and he suggests this complexity will increase as more evidence is discovered.
Researchers from UiB and Witswatersrand are looking closer at technology used by different groups in this and other regions in South Africa, such as spear points made of stone, and decorated ostrich eggshells. They hope to determine whether an overlap occurred and contact made across groups of Middle Stone Age humans.
“The pattern we are seeing is that when demographics change, people interact more. For example, we have found similar patterns engraved on ostrich eggshells in different sites. This shows that people were probably sharing symbolic material culture, at certain times but not at others,” says Dr Karen van Niekerk, a UiB researcher.
Contact and sharing between groups may well have been vital to the survival and societal evolution of Homo sapiens as far back as 100,000 years ago. Certainly, our ability to collaborate in order to solve problems prepared us for our journey out of Africa.
“Contact across groups, and population dynamics, makes it possible to adopt and adapt new technologies and culture and is what describes Homo sapiens. What we are seeing is the same pattern that shaped the people in Europe who created cave art many years later,” says Henshilwood.