Archaeological Shellfish Size and Later Human Evolution in Africa

Author(s): Richard Klein

Year: 2015


About 50,000 years ago, modern humans expanded from Africa to Eurasia. Significant behavioral change accompanied this expansion, and archaeologists commonly seek its roots in the African Middle Stone Age (MSA) before 50,000 years ago. Easily recognizable art objects and "jewelry" become common only in sites that postdate the MSA in Africa and Eurasia, but some MSA sites contain possible precursors. Population growth is the most popular explanation for these precursors and for the post-MSA florescence of art. Economically important gastropods from coastal sites in South Africa allow a test this idea, since the number of human collectors is probably the principal determinant of average gastropod size. In every examined gastropod species, average size is similar in MSA layers with precocious artifacts and those without, and MSA gastropods are always substantially larger on average than those in succeeding Later Stone Age (LSA) layers that formed under equivalent environmental conditions. The sum suggests that whatever the cognitive implications of precocious MSA artifacts, they were not associated with population growth. MSA populations remained consistently small by LSA standards, and a substantial increase in population size is obvious only at the MSA/LSA transition, when it is dramatically reflected in the Out-of-Africa expansion.

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Cite this Record

Archaeological Shellfish Size and Later Human Evolution in Africa. Richard Klein. Presented at The 80th Annual Meeting of the Society for American Archaeology, San Francisco, California. 2015 ( tDAR id: 394838)


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min long: -18.809; min lat: -38.823 ; max long: 53.262; max lat: 38.823 ;