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El ADN de los coprólitos humanos pre-Clovis en Oregón, América del Norte
M Thomas P Gilbert1, Dennis L Jenkins, Anders Götherstrom
1Centre for Ancient Genetics, University of Copenhagen, Universitetsparken 15, 2100 Copenhagen, Denmark.
Science (New York, N.Y.)
|April 5, 2008
Resumen
La presencia humana temprana en las Américas está confirmada por la evidencia de ADN antiguo de Oregon, que es anterior a la cultura Clovis por más de 1000 años. Este hallazgo desafía las líneas de tiempo establecidas para la primera migración humana a América del Norte.
Área de la Ciencia:
- Arqueología Arqueología.
- La paleogenética es la paleogenética.
- La Antropología Antropología Antropología.
Sus antecedentes:
- La línea de tiempo de la migración humana inicial a las Américas es un tema de debate en curso.
- La aparición del complejo tecnológico de Clovis, fechado aproximadamente 11.00010.800 años de radiocarbono antes del presente (14C años BP). ), es un punto de referencia clave.
Objetivo del estudio:
- Para investigar el momento de la presencia humana en América del Norte.
- Para determinar si los humanos ocuparon sitios en América del Norte antes del complejo de Clovis.
Principales métodos:
- Recuperación de ADN mitocondrial humano (mtDNA) de antiguos coprolitos encontrados en las cuevas de Paisley 5 Mile Point en Oregon.
- La datación directa de los coprolitos mediante espectrometría de masas de acelerador (AMS).
- Análisis del ADNmt para identificar haplogrupos.
Principales resultados:
- El ADNmt humano fue identificado en coprolitos de las cuevas de Paisley 5 Mile Point Caves.
- El ADNmt recuperado pertenece a los haplogrupos fundadores A2 y B2 de los nativos americanos.
- La datación directa de las coprolitas arrojó edades de 12.300 años 14C BP, más de 1000 años antes que el complejo de Clovis.
Conclusiones:
- Los seres humanos estuvieron presentes en el sur-centro de Oregón por al menos 12.300 14C años B.P.
- Esta presencia humana es significativamente anterior al complejo tecnológico de Clovis.
- Los hallazgos sugieren una primera migración humana a las Américas más temprana de lo previamente establecido.
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