A S C S 0 9 : P r o c e e d i n g s o f t h e 9 t h C o n f e r e n c e o f t h e A u s t r a l a s i a n S o c i e t y f o r C o g n i t i v e S c i e n c e Article DOI: 10.5096/ASCS200925 1 6 2 The Evolution of Technical Competence: Strategic and Economic Thinking Ben Jeffares (Ben.Jeffares@vuw.ac.nz) Philosophy Program, Victoria University of Wellington Wellington, New Zealand Abstract This paper will outline a series of changes in the archaeological record related to Hominins.1 I argue that these changes underlie the emergence of the capacity for strategic thinking. The paper will start by examining the foundation of technical skills found in primates, and then work through various phases of the archaeological and paleontological record. I argue that the key driver for the development of strategic thinking was the need to expand range sizes and cope with increasingly heterogeneous environments. Keywords: Human Evolution; Strategic Thinking; Archaeology; Hominins; Introduction In recent decades, discussions of human cognitive evolution have frequently focused on social skills. Humans are, so the argument goes, hyper-social. This hyper-sociality underpins all other uniquely human achievements, as it allows for, and requires, co-operation, co-ordination, pooled information, specialisation, language use, et cetera. Consequently, cognitive scientists have focused on the question: How did humans evolve to be hyper-social? Collections such as the Byrne and Whiten edited "Machiavellian Ape," (1988), and monographs such as Robin Dunbar's "Grooming, gossip and the evolution of language," (1996), to name but two, are early examples of work on the cognitive skills associated with social complexity. The implication is that human evolution has been shaped almost entirely by developments in the social sphere, and that the uniqueness of human beings is the result of our sociality. In somewhat stark contrast archaeologists have developed increasingly sophisticated reconstructions of hominin behaviours associated with stone tools and other aspects of the material world. Rich behavioural reconstructions of our hominin ancestors in detailed ecological and social settings are becoming commonplace (See for instance Odell, 1996). This paper is part of a broader project that integrates these two strands of research: the evolutionary cognitive sciences and the archaeological sciences. It takes a lead from Steven Mithen's (1996) "The Prehistory of the Mind," and subsequent work by people such as Thomas Wynn (Coolidge & Wynn, 2009; Wynn, 2002), showing that the archaeological and physiological evidence, coupled with that from cognitive science, constrains speculations about 1 Recent genetic work has broadened the term Hominid to include the chimpanzees Pan Paniscus and Pan troglodytes. The term Hominin refers to the Homininae, the bi-pedal primates: the Australopithecines and Homo genus. human cognitive evolution. Cognitive science and archaeology potentially illuminate one another. On this view, tools, their manufacture and use, should not be incidental to our understanding of our evolutionary past: They should be central. This should come as no surprise to cognitive scientists. As the cognitive sciences increasingly come to see minds as embodied, extended, and embedded in their environmental contexts, stone tools become less the detritus of the human past, and more the fossilised hard parts of ephemeral thoughts. This paper looks at one strand of human cognition: the ability to engage in strategic planning. I examine the archaeological record and seek to identify the emergence of this skill in its evolutionary context. It will do so by examining the archaeological record in a chronological order, showing the subtle shifts in skills that underpin stone tool making, starting with the primate background, and progressing through to the technologies associated with Homo sapiens. The Shared Legacy Extant primates are in fact the few isolated survivors of a diverse and widespread group that flourished in the Miocene (Cameron, 2004; Cameron & Groves, 2004). Of the large primates, Homo sapiens are most closely related to Pan Paniscus and Pan Troglodytes (the chimpanzees). Consequently, features shared by Pan and Homo are probably homologies: features common to all of the human ancestors. Large mammals like the primates, particularly K-selected organisms, tend to have offspring that require high parental investment (Foley, 1987). Consequently, offspring tend to be born singly, and spaced apart to allow for long periods of growth, dependency and learning. High levels of sociality and interaction, coupled with this long period of dependence, provides a robust platform for social learning in the primates, as it does in many other species (See for instance Rendell & Whitehead, 2001). Behaviour is structured by the opportunities provided by the physical environment through exploration and play, coupled A S C S 0 9 : P r o c e e d i n g s o f t h e 9 t h C o n f e r e n c e o f t h e A u s t r a l a s i a n S o c i e t y f o r C o g n i t i v e S c i e n c e Article DOI: 10.5096/ASCS200925 1 6 3 All apes are manually dexterous, and the great apes all show signs of basic tool using. Chimpanzees are notable for their use of percussive technologies, with nut cracking being a familiar example from a repertoire of percussive technological culture (Andrew Whiten, Schick, & Toth, 2009). The combination of manual dexterity and observation of parents manifests itself in long, and frequently complex, extractive foraging behaviours (Coolidge & Wynn, 2009). Apes are capable of learning long sequences of chained actions that lead to a goal.2 So 2 Like extended childhood, complex signalling or sociality, this is not a uniquely hominid trait. New Caledonian crows appear to The Evolutionary Timetable. For our purposes, we require only a broad outline view our evolutionary history. Hominin Species. The last common ancestor of chimpanzees and humans was approximately 5-6 million years ago (mya). In Eastern and Southern Africa, there emerged the Australopithecines, bi-pedal primates and the first hominins. This included species such as A. Anamensis, A. Afarensis, and A. Africanus and possibly others. With the increased drying of the African continent, the Australopithecines appear to have split into two lineages; the Paranthropines (P. Robustus, P. Boisei) seem to have become adapted to chewing larger quantities of seeds and vegetable matter. The Paranthropines as a group went extinct. Early Homo used increasingly obvious tools, was more gracile in build, and probably included more meat in their diet. Early Homo includes species such as H. Habilis and H. Rudolfensis. From Early Homo there emerged the erectus grade, labelled here Erectines. H. Erectus was human sized, long legged, but with a smaller brain and a simple technology. Given the Erectines spread across Africa and Eurasia, it seems likely that H. erectus sensu lato included a number of species, and Colin Groves suggests that the Erectines might include H. Erectus, H. Pekenensis, and H. Georgicus (Cameron & Groves, 2004). The Archaic Sapiens, or Sapients group includes H. Heidelbergensis, H. Neandertalensis, and H. Sapiens. Technologies. Technology does not overlap directly with species or species groups, and more often than not, there is a lag between the emergence of a new species/evolutionary grade, and new technological forms. However, given the scarcity of fossils, and uncertainty with dates, we can broadly link species and tools. Mode 1 tools are simple chopping tools and flakes, and they appear approximately 2.6 million years ago in Africa with the Homo genus, and appear in Europe soon after. Mode 2 tools are the classic Acheulean Handaxes and associated with the Erectines, particularly H. Erectus sensu lato. These tools are bi-facially flaked tools, and many seem to be manufactured to a standardised teardrop shape. Mode 3 tools are manufactured from a prepared core. This two-step process has an initial piece of raw material that is shaped, and from this large, uniform flakes are removed. These standardised flakes are in turn shaped into different tools. Mode 3 technology is associated with Homo neandertalensis and other Archaic sapiens, particularly Homo heidelbergensis. It shows increased diversity and specialisation of tools and some recent analyses suggest the emergence of regionalisation, and local tool making traditions, suggestive of increased pedagogy and directed learning. Mode 4 Tools (unmarked on this diagram) represent the emergence of blades, finer worked stone tools, and is generally considered to represent the emergence of a full human suite of tools. It emerges about 200kya but it potentially began developing much earlier. A S C S 0 9 : P r o c e e d i n g s o f t h e 9 t h C o n f e r e n c e o f t h e A u s t r a l a s i a n S o c i e t y f o r C o g n i t i v e S c i e n c e Article DOI: 10.5096/ASCS200925 1 6 4 another homology of the hominins is this capacity for multistage food extraction, with preparatory activities that in some cases involve tools and tool preparation, as part of a chained sequence of behaviours. Given this common ancestry, we can presume with a high degree of confidence that even before archaeologists can see tools in the archaeological record, early hominins possessed a substrate of skills associated with tools, tool manufacture, and manipulation of the external world. They engaged in long extractive foraging sequences. Their extractive sequences involved the manipulation of tools and materials. And, the sequences were learnt in a group context through observation of adults and peers, and were potentially fine tuned to the local environment. All hominins had tool making and tool using cultures. The Australopithecines With the drying of the east coast of Africa, pockets of the last common ancestor of chimps and humans found themselves in increasingly novel environments. Instead of homogenous forest habitats, the east coast of Africa became ecologically variable. There were areas of acacia forest, bushland, denser forested environments around rivers, as well as environments that were more open and savannah like. Early bi-pedal hominins, the Australopithecines such as A. afarensis, and A. Australopithecus, were in a heterogeneous landscape. In such a heterogeneous environment, both extractive foraging sequences and cultural learning would play and increasingly important role. Extractive foraging, abetted by technical skills, may even have had an expanded role in the Australopithecine foraging repertoire. Cultural learning might have fine-tuned these skills to a new level of adaptive significance. A group with a cultural tool using skill such as marrow extraction from abandoned carcasses, or tuber extraction from the roots of a plant, may have had a crucial adaptive edge that enabled them to flourish, regardless of which disparate piece of the world they found themselves in. The archaeological record of such skills is probably invisible. Rocks used opportunistically by hominins are indistinguishable from geologically abundant material (E. S. Savage-Rumbaugh & Lewin, 1994) without close microscopic examination that might reveal distinctive wear- show a similar talent for long complex extractive foraging sequences (See the work by Hunt and Gray: Gavin R. Hunt & Gray, 2002; Gavin. R. Hunt & Gray, 2004; G. R. Hunt, Rutledge, & Gray, 2007). What is unique to humans is the particular combination of traits possessed: high levels of sociality, manipulation and extractive foraging, long periods of offspring dependency, spatially and temporally variable environments, complex signaling systems, and so forth. No other organism has this complete "package" of skills. patterns. However, we can assess the increasing importance of such skills by clues in the physiological record. For a start, the emergence of bi-pedalism should not be underestimated. Overlooked in many modern studies of human cognitive evolution, bi-pedalism was long considered a major milestone by prior generations of paleoanthropologists (Landau, 1984, 1991). Bi-pedalism frees the hands, allows for the unencumbered arms to gesture, and crucially for our interest here, it enables hominins to carry things efficiently. Increased ability to carry things efficiently allows for the movement of goods between locations, and changes the potential uses of the landscape markedly. The efficient transfer of resources was potentially crucial, as it allowed for the exploitation of a range of habitats. One could forage in one location, but retreat to safety in another. One might process a food in one location, but consume it in another. This means that behavioural sequences associated with extractive foraging would have to stretch to accommodate this new possibility for the exploitation of space. It's also worth noting that not just tools and food that could be carried: Infants, carried frontally, gain the potential to engage in dual monitoring of parents and their parents' world (S. Savage-Rumbaugh, 1994). The Australopithecine Legacy The Australopithecines were something more than upright chimpanzees. With the common ancestry of technologically aided food extraction, the Australopithecines were actively engaging with technology at some level. Crucially, bipedality suggests that transportation of foodstuffs and material over distances are features of the Australopithecine world. Behavioural sequences are under pressure to stretch Figure 1: Basic Extractive Sequence. All Hominids (Chimps and Hominins) can engage in extractive foraging sequences that involve manual manipulation and preparatory work before access is gained to food. These sequences are typically done in a single location over a limited time frame, and can be seen as a chained behavioural sequence. Individuals can learn their own variant of such a sequence, but the substrate, the materials used as tools and the target food, are culturally learnt. The use of stone in such sequences acted as a precursor to visible stone tool technologies.