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Oldest Stone Tools Predate Previous Record Holder By 700,000 Years
derekmead writes: The oldest stone tools ever found have been discovered by scientists in Kenya who say they are 3.3m years old, making them by far the oldest such artifacts discovered. Predating the rise of humans' first ancestors in the Homo genus, the artifacts were found near Lake Turkana, Kenya. More than 100 primitive hammers, anvils and other stone tools have been found at the site. An in-depth analysis of the site, its contents, and its significance as a new benchmark in evolutionary history will be published in the May 21 issue of Nature.
How does one tell the difference between a chunk of rock and a 3.3 million year old tool? Because they both look fucking indistinguishable to me: they're both just chunks of rock.
Well firstly, if you know about geology and how erosion works you can tell the difference between a coincidentally shaped rock and a purposefully shaped rock. This difference is even more pronounced if you are also a good flintknapper sort of like a cop can spot an expertly forged bank note. Secondly there is forensics, tool manufacture leaves distinctive marks and so does tool use. Even if somebody randomly smashed a rock and used a sharp flake to butcher an animal you would see the distinctive wear patterns on the flake. You might even find trace evidence on the tool if you are lucky. This is why it is a huge mistake to wash a recently discovered stone tool because even after tens of thosands of years you can sometimes tell what a tool was last used to cut, scrape, drill or hack apart. Thirdly, there is context. You often find tools at a site where animals were butchered, where tools were made or if you are very lucky in a place where people lived for a while. Perhaps a fire was lit, which can give a date. Bones with distinctive tool marks you only get through systematic butchery and bones that have been smashed to get at marrow are a dead give-away. These bones are also useful for dating associated tools as are layers of volcanic ash, lava or sediments and attributes of the stone tools themselves can also give date information.
There is a lot of controversy on this. As a rule you can't tell from one artifact, it's the number of them and their arrangement that matters most. Key to understanding is the Hollywood version is backwards. Usually in Hollywood you take the a stone and remove stuff till you are left with a tool, like whittling a point on a stick. In reality the bits you take off are the tools. What you have in your hand is a core.
This gives you key pieces to look for, cores being high on the list. Cores are distinctive. The process of making many flakes of a similar size off the core creates a regular and distinct size and shape. They are more rounded at one end, the handle, and then it tapers roughly. There are clear angles and planes to cores. You can tell of the knapper was right handed or left handed. Then you have lots of very regular sized flakes and the core they are off. If you are anal enough - a defining characteristic of archaeologists - you can reassemble the original stone from the cores and flakes. You also have work places for this. It takes some work to make stone tools, so you made a batch at a time. So you have small stone tool work stations. Since they were temporary they were just abandoned as is. An archaeologist can sometimes just sit down and pick up where the original worker had left off.
If you Google "Flint Core" in images you can see pics of many.