Introduction to the Stone Age: Why is this significant?
The Stone Age is really the start of the archaeological record, at least in the sense that is only stones that have been manipulated into useful tools are what scientists find when they dig in "archaeologically ancient soils." Long ago, human precursors began to use stone tools, about 2.6 million years ago. Does this mean they did not use other materials as tools, such as tree branches, hardened roots or bones and teeth of various animals? No it does not, but we have no evidence in the very beginning that tools other than small river cobbles that had been bashed together either intentionally or unintentionally to produce sharp edges, presumably to cut something, show up in ancient soils located in Africa. In fact, when people used to talk about "the stone age," they were generally referring to cultural time frames of stone tool technology found only in Africa.
The Stone Age, as many have pointed out, is broken down into three major periods: The Early Stone Age (3million years ago to 200 thousand years ago), The Middle Stone Age (200 thousand years ago to about 40 thousand years ago) and The Late Stone Age (40 thousand years ago to the advent of ceramics and metals). But depending on the particular site where stone tools have been excavated and studied, there can be dozens of sub-categories to better define the trajectory of stone tool use and manufacturing practices over geologic time and across geographical space. So what do we call stone tool cultural time frames outside of Africa? That is when we use terms like the Paleolithic, Mesolithic, and Neolithic, respectively. Although the terms are used interchangeably these days, one has to be careful when doing so because the time frames in which humans and/or our precursors were present in those areas and the technological bauplan for their tool kits can be very different.
It is facinating to think that there are landscapes out there that one can walk on that just happen to fall within the geological time frame when stone tools might be present. A great example of this can be experienced on the escarpments of Ethiopia. As one travels on soil that can be dated back 3 million years ago, not one stone tool can be found, but thousands of animal bones, including some of our most ancient human precursors. But just a few more kilometers of travel, up and down steep hills of eroding soils, stone tools litter the surface, but animals bones almost become nonexistant. Within those few kilometers, you travel closer in time to the present, and because the region just happened to be enviromentally favorable for early humans, after the point when they collectively decided to use stones as tools. It is this simple recognition that is the most significant realization about the Stone Age. Let me explain.
Using tools and maniputing objects as tools is not a human hallmark. Animals of all kinds use tools, whether it be the river otter using a rock to bash open shellfish, or a chimpanzee using a long blade of grass to fish for termites. In all actuallity, our human precursors that lived approximately 3 million years ago in Africa may have observed other animals manipulating oblects and using them as tools. After doing so, they may have immitated their animal neighbors and used tools that unfortunatley do not survive the rigors of fossilization. And that is where it all began, until our inability to remain bored led to exploring the use of stones as tools, which opened up a whole new network of feeding possibilities, from digging for tubers to cutting meat off of carcasses and breaking open bones to get to the fatty-rich marrow.
After reviewing the stone tool ages, it is not the tool kits that impress me the most; even though many of the more recent kits are eloborate and extremely difficult to reproduce. It is the significant moment that our early human precursors made a conscious decision to use stone as a raw material for making a tool. This may not seem so significant, but in order for their newly found need for stone as a reliable tool, they had to choose the right kind of stone that would withstand the mechanical challenges of being bashed together to form sharp edges. Not every rock out there will work, and those early human precursors would travel great distances to find the appropriate raw material. This is why the Stone Age is a meaningful moment in our history and prehistory.