Of Stone Tools and Human Cognition

One of the things that is taught in human origins classes all over the world is that the earliest stone tools were likely made at the site of Dikika, and date to around 3.4 million years ago.  That perspective has now been called into question with the observation that monkeys can create exactly the same kinds of tools—by accident. Sarah Knapton, writing in the Telegraph has this:

In a discovery that calls into question decades of research, a band of wild bearded capuchin monkeys in Brazil were seen hammering rocks to extract minerals, causing large flakes to fly off.

Previously archaeologists believed the flakes were only made by humans through a process called ‘stone-knapping’ where a larger rock is hammered with another stone to produce sharp blade-like slivers which can be used for arrows, spears or knives.

The flakes were thought to represent a turning point in human evolution because they demonstrated a level of planning, cognition and hand manipulation that could not be achieved by other animals.

But the new research suggests that flakes can be made without any such foresight. In fact they can simply be made by accident.

“The fact that we have discovered monkeys can produce the same result does throw a bit of a spanner in the works in our thinking on evolutionary behaviour and how we attribute such artefacts,” said Dr Michael Haslam, lead of the Primate Archaeology project at the University of Oxford.

This is possible and it may be that some of the earliest “tools” aren't any such thing. When hominins started using tools in a concerted fashion has always been a large question in the evolutionary picture. It is very clear that by what we know as the Acheulean, manufactured by Homo ergaster, Homo erectus and Homo heidelbergensis, the hand axes are clearly human-made. Before that, maybe more research needs to be done to verify that what we think is human behavior actually is.  It is natural to want to impart human intelligence to our ancestors as far back as we can, in an effort to “humanize” them but, sometimes, this might be just wishful thinking.