Laine Clark-Balzan

Rethinking the dispersal of Homo sapiens out of Africa.

Current fossil, genetic, and archeological data indicate that Homo sapiens originated in Africa in the late Middle Pleistocene. By the end of the Late Pleistocene, our species was distributed across every continent except Antarctica, setting the foundations for the subsequent demographic and cultural changes of the Holocene. The intervening processes remain intensely debated and a key theme in hominin evolutionary studies. We review archeological, fossil, environmental, and genetic data to evaluate the current state of knowledge on the dispersal of Homo sapiens out of Africa. The emerging picture of the dispersal process suggests dynamic behavioral variability, complex interactions between populations, and an intricate genetic and cultural legacy. This evolutionary and historical complexity challenges simple narratives and suggests that hybrid models and the testing of explicit hypotheses are required to understand the expansion of Homo sapiens into Eurasia.

The Middle Palaeolithic of the Nejd, Saudi Arabia

The Pleistocene archaeological record of the Arabian Peninsula is increasingly recognized as being of great importance for resolving some of the major debates in hominin evolutionary studies. Though there has been an acceleration in the rate of fieldwork and discovery of archaeological sites in recent years, little is known about hominin occupations in the Pleistocene over vast areas of Arabia. Here we report on the identification of five new Middle Palaeolithic sites from the Nejd of central Arabia and the southern margins of the Nefud Desert to the north. The importance of these sites centers on their diversity in terms of landscape positions, raw materials used for lithic manufacture, and core reduction methods. Our findings indicate multiple hominin dispersals into Arabia and complex subsequent patterns of behavior and demography.