From Biological to Cultural Evolution
The conceptual framework of extended evolution is general enough not to force upon us a premature distinction between biological and cultural evolution, nor to reduce the latter to a metaphorical generalization of the former. An embedded network of actors, actions and their results may describe a population of our prehuman ancestors just as well as they describe a human society. The relevant regulative structures and environments will be different, but the concept is wide enough to allow for the identification of processes connecting one with the other in an evolutionary continuum.
The evolutionary mechanism giving rise to specifically human ways of thinking is often described in terms of distinct thresholds, involving ecological circumstances that drive humans into more cooperative ways of life and foster adaptations for dealing with problems of social coordination. In his recent book A Natural History of Human Thinking (2014) Michael Tomasello emphasizes the cooperative nature of human thinking. He postulates two key evolutionary steps. In the first step, a novel type of small-scale collaboration in human foraging led to socially shared joint goals and joint attention, creating a possibility for individual roles and perspectives within ad hoc situations. In the second step, which is characterized by growing human populations competing with each other, humans developed collective inten- tionality, enabling them to construct a common cultural ground by means of shared cultural conventions, norms, and institutions. The evolutionary mechanism is described in terms of ecological circumstances driving humans into more cooperative ways of life and fostering adaptations for dealing with problems of social coordination.
Against the background of extensive empirical studies involving comparisons between children and apes, Tomasello identifies the specific cognitive abilities emerging in these two evolutionary steps, which are designated as joint and collective intentionality, respectively. Joint intentionality is characterized by the fact that humans can conceptualize the same situation under different perspectives, that they can make recursive inferences about each other’s intentional states and that they can evaluate their own thinking with respect to the normative perspectives of others. Collective intentionality extends joint intentionality to include a conventional dimension of these cognitive capabilities which are now broadly shared within a culture and no longer a matter of ad hoc situations.
In this picture, specific forms of human thinking thus become first the presupposition and then the consequence of human culture. Less emphasis, on the other hand, is given to the evolving results of human thinking in the form of knowledge, institutions and material culture emerging and accumulating from human interactions with their environment over time. Instead of postulating two distinct evolutionary steps leading from biological to cultural evolution, our model suggests a continuously working feedback mechanism in which the ecological circumstances cited by Tomasello as evolutionary driving forces are themselves partly created by the regulative structures of human evolution through niche construction. Therefore, we would like to emphasize, more than Tomasello did, the material aspect of human actions, not only their instrumental but also their representational aspects, which are crucial for the transmission and transformation of the evolving regulative structures. Material representations of thinking, for instance, may function as external memory, as catalysts for the emergence of different perspectives and as triggers for reflection, and thus affect all the dimensions of thinking processes mentioned by Tomasello.