Cognition: From Capuchin Rock Pounding to Lomekwian Flake Production

Abstract

Although it is sometimes suggested that modern-day chimpanzee nut-cracking behaviour is cognitively similar to early stone-tool-knapping behaviour, few systematic comparative studies have tested this assumption. Recently, two further techno-behaviours were reported that could both represent intermediary phases in hominin cognitive evolution pertaining to our ultimate technological astuteness. These behaviours are that of bearded capuchin monkeys pounding rocks and very early stone-tool knapping from Lomekwi 3. Here we use a multi-model approach to directly compare cognitive aspects required for 11 techno-behaviours, ranging from the simplest capuchin pounding behaviour to the most complex chimpanzee nut-cracking and Lomekwi 3 knapping behaviours. We demonstrate a marked difference in broad-spectrum cognitive requirements between capuchin pounding on the one hand and Lomekwian bipolar knapping on the other. Whereas the contrast is less pronounced between chimpanzee nut-cracking scenarios and basic passive-hammer knapping at Lomekwi 3, the escalation in cognitive requirement between nut cracking and bipolar knapping is a good indication that early hominin flaking techniques are cognitively more taxing than chimpanzee nut-cracking behaviour today.