Between 300,000 and 250,000 years ago early humans in Africa and Eurasia began to use durable material substances and objects as media for signaling. Initially material signals were confined to ochre and other pigments, but over time objects such as beads were also added as technologies for sending messages. Changes in the types of materials used, their durability and costs, and the contexts of their disposal indicate a series of transitions in how early humans employed signaling media. Signaling theory from (...) biology suggests that shifts in technologies over the course of the Pleistocene reflect problems in coordinating action and resolving conflicts within increasingly large and internally differentiated societies. (shrink)

Beads and other ‘body ornaments’ are very widespread components of the archaeological record of early modern humans (Homo sapiens). They appear first in the Middle Stone Age in Africa, and somewhat later in the Early Upper Paleolithic of Eurasia. The manufacture and use of ornaments is widely considered to be evidence for significant developments in human cognition. In our view, the appearance of these objects represents the interaction of evolved cognitive capacities with changing social and demographic conditions. Body ornamentation is (...) a medium or technology for communication, particularly of socially-relevant information. The widespread adoption of beads and other discrete objects as media for communication implies changes in the complexity and stability of social messages, as well as the scale of social networks. The relatively sudden appearance of beads in the Paleolithic archaeological record coincides with genetic and archaeological evidence for expansion of human populations. We argue that these changes reflect expanding scales of social interaction and more complex social landscapes resulting from unprecedentedly large and internally differentiated human populations. (shrink)

Evolutionary Transitions in Individuality have been responsible for the major transitions in levels of selection and individuality in natural history, such as the origins of prokaryotic and eukaryotic cells, multicellular organisms, and eusocial insects. The integrated hierarchical organization of life thereby emerged as groups of individuals repeatedly evolved into new and more complex kinds of individuals. The Social Protocell Hypothesis proposes that the integrated hierarchical organization of human culture can also be understood as the outcome of an ETI—one that produced (...) a “cultural organism” from a substrate of socially learned traditions that were contained in growing and dividing social communities. The SPH predicts that a threshold degree of evolutionary individuality would have been achieved by 2.0–2.5 Mya, followed by an increasing degree of evolutionary individuality as the ETI unfolded. We here assess the SPH by applying a battery of criteria—developed to assess evolutionary individuality in biological units—to cultural units across the evolutionary history of Homo. We find an increasing agreement with these criteria, which buttresses the claim that an ETI occurred in the cultural realm. (shrink)