So Much for Stone Tools

There goes the flaked stone tool as a measure of hominin intelligence, now that monkeys can unintentionally make them, too.

Side by side, they look identical. Watch the video on Nature: capuchin monkeys are shown banging rocks for no good reason. The products, however, look the same as stone tools often used as a gauge of human intelligence. As humanity arose from the apes—as we’ve been told for decades—their use of stone tools improved, signalling the dawn of big-brained Homo. Ewen Calloway’s headline reads, “Monkey ‘tools’ raise questions over human archaeological record.” Callaway explains what those questions are:

The capuchins make the fragments unintentionally while bashing rocks into dust, the researchers find. Some scientists say that the results call into question whether some stone tools have been incorrectly attributed to hominins — including 3.3-million-year-old artefacts from Kenya that are the oldest on record.

Other sources are moaning as well:

• One sharp edge does not a tool make (Nature News)
• Monkeys Break Rocks, Show Humans Aren’t So Special (Live Science)
• Monkeys are seen making stone flakes so humans are ‘not unique’ after all (PhysOrg)
• Some of our Stone Age tools may just be crafty monkey throwaways (New Scientist)

National Geographic, champion of early-man evolution tales, has not chimed in yet on this finding. Maybe it’s because it is embarrassing. For decades, NG has shown photos of the stone tools made by Homo habilis (handyman) and other hominins as proof of their evolving intelligence.

It’s not clear why the capuchin monkeys bang rocks like this. It appears they like to lick the dust inside. The researchers note that the monkeys do not use the flaked rocks after they make them. But if the products are identical to the supposed human stone tools, how can one use them as a gauge of the evolution of intelligence? Only more advanced tools, such as those carved and fastened onto handles with adhesives, could show intention and mindfulness. From now on, flaked rocks are apparently ambiguous.

What will this do to the Darwin early-man storytelling empire? This is funny because it plays right into the intelligent design movement’s hands. One design principle involves intentionality. Two artifacts may look identical (e.g., modern art vs. paint spilled on a canvas; natural radio pulses from space vs. a message from aliens). Intelligent design seeks to differentiate between intentional causes and non-intentional causes. These rocks have been mistaken for tools, but they aren’t tools if the monkeys aren’t using them intentionally as tools.