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Evidencia de ADN antiguo para el origen del Viejo Mundo de los perros del Nuevo Mundo
Jennifer A Leonard1, Robert K Wayne, Jane Wheeler
1Department of Organismic Biology, Ecology and Evolution, University of California, Los Angeles, CA 90095-1606, USA. Leonard.Jennifer@NMNH.SI.edu
Science (New York, N.Y.)
|November 26, 2002
Resumen
El ADN de perros antiguos de las Américas revela orígenes de múltiples linajes del Viejo Mundo. Un linaje único de perros del Nuevo Mundo, ausente en los perros modernos, sugiere que los colonos europeos interrumpieron las poblaciones de perros nativos.
Área de la Ciencia:
- La paleogenómica es la paleogenómica.
- Evolución de la evolución canina.
- Arqueogenética La arqueogenética.
Sus antecedentes:
- El origen y la diversificación de los perros domésticos (Canis lupus familiaris) están relacionados con las migraciones humanas.
- Comprender la historia genética de los perros en las Américas proporciona información sobre las interacciones entre humanos y perros precolombinas.
Objetivo del estudio:
- Para investigar los orígenes y la diversidad genética de los antiguos perros en las Américas utilizando el ADN mitocondrial.
- Para determinar la relación entre los antiguos perros americanos y las poblaciones de perros del Viejo Mundo.
- Para explorar el impacto de la colonización europea en los linajes de perros nativos americanos.
Principales métodos:
- Secuenciación de ADN mitocondrial (mtDNA) de restos de perros antiguos de América Latina y Alaska.
- Análisis filogenético para comparar las secuencias antiguas con el Viejo Mundo y los linajes de perros modernos.
- Análisis genéticos de poblaciones para identificar clado únicos y evaluar la diversidad genética.
Principales resultados:
- Los antiguos perros americanos se originaron a partir de múltiples linajes de perros del Viejo Mundo que emigraron con los humanos a través del estrecho de Bering.
- Se identificó un clado distinto de ADN mitocondrial, único en el Nuevo Mundo, lo que indica un período de aislamiento geográfico.
- Este clado único del Nuevo Mundo estaba notablemente ausente en una gran muestra de perros modernos.
Conclusiones:
- Los perros nativos americanos trazan su ascendencia a múltiples introducciones independientes del Viejo Mundo.
- La distinción genética de los perros del Nuevo Mundo destaca un período de aislamiento después de su llegada inicial.
- La desaparición del único clado de perros nativos sugiere su supresión sistemática por parte de los colonos europeos, lo que afecta a las poblaciones caninas indígenas.
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