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Cronología de la transición de la Edad de Piedra Acheulean a la Edad Media en el este de África
Alan L Deino1, Anna K Behrensmeyer2, Alison S Brooks3,4
1Berkeley Geochronology Center, Ridge Road, Berkeley, CA 94709, USA. adeino@bgc.org pottsr@si.edu.
Science (New York, N.Y.)
|March 17, 2018
Resumen
La transición de la Edad de Piedra Media (MSA) en Kenia comenzó hace unos 320.000 años, marcando un cambio de la fabricación de herramientas de Acheulean. Este estudio proporciona la evidencia más antigua de artefactos MSA en el este de África.
Área de la Ciencia:
- Paleoantropología
- Arqueología
- Geocronología
Sus antecedentes:
- La Edad de Piedra Media (MSA) significa un período crucial de innovación tecnológica y desarrollo cultural vinculado a la evolución humana.
- El Acheulean, una larga tradición de fabricación de herramientas de piedra, precedió al MSA.
Objetivo del estudio:
- Establecer una cronología precisa para la transición del Acheulean a la MSA en la cuenca de Olorgesailie, Kenia.
- Hasta la fecha, los depósitos sedimentarios ricos en artefactos asociados con estos períodos.
Principales métodos:
- Datamiento del argón-40 y el argón-39
- Datamiento de las series de uranio
- Análisis de depósitos sedimentarios y conjuntos de artefactos
Principales resultados:
- Los conjuntos de herramientas de Acheulean tardío fueron fechados entre 615.000 y 499.000 años atrás.
- Una transición tecnológica y faunal significativa ocurrió después de hace 499.000 años.
- El MSA definitivo, desprovisto de elementos acheuleanos, comenzó hace al menos 305.000 años.
Conclusiones:
- Los hallazgos establecen la cuenca de Olorgesailie como el depósito más antiguo de artefactos MSA en el este de África.
- El estudio refina la línea de tiempo para la evolución tecnológica humana temprana en la región.
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