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Aleutas, nutrias marinas y otras comunidades de estado estable alternativas
Science (New York, N.Y.)
|April 28, 1978
Resumen
La presa aleuta en la isla de Amchitka cambió dramáticamente en 2500 años. Este cambio probablemente se debió a la sobreexplotación aleuta de las nutrias marinas, no a los cambios culturales en las preferencias alimentarias.
Área de la Ciencia:
- Paleoecología Paleoecología.
- Arqueología Arqueología.
- Ecología marina Ecología marina.
Sus antecedentes:
- Los montes prehistóricos aleutianos en la isla Amchitka revelan cambios faunísticos a largo plazo.
- Los ecosistemas cercanos a la costa de las Aleutianas exhiben dos estados estables: dominados por macroalgas o herbívoros epibéticos.
- Las poblaciones de nutrias marinas influyen críticamente en estos estados del ecosistema.
Objetivo del estudio:
- Para reexaminar la selección de presas aleutianas prehistóricas durante 2500 años.
- Para investigar los impulsores de los cambios observados en la dieta aleutiana.
- Para correlacionar los cambios faunísticos con datos paleoecológicos.
Principales métodos:
- Análisis de restos faunísticos estratificados de un medio aleutiano.
- Comparación de datos faunísticos con estudios ecológicos en comunidades aleutianas cercanas a la costa.
- Modelado ecológico de la dinámica depredador-presa.
Principales resultados:
- Se identificaron cambios significativos en las presas aleutianas durante el período de ocupación de 2500 años.
- Los cambios de fauna se correlacionan con los requisitos ecológicos para la presencia o ausencia de nutrias marinas.
- La evidencia sugiere la sobreexplotación de la nutria marina local por parte de los aleuts aborígenes.
Conclusiones:
- Los cambios en la composición de las presas de Aleut reflejan la dinámica de la población de nutrias marinas.
- Los cambios en la dieta fueron impulsados por factores ecológicos, específicamente la disponibilidad de nutrias marinas, en lugar de la preferencia cultural.
- Las prácticas de caza aleutianas aborígenes probablemente llevaron a la disminución de la nutria marina local, lo que afectó a los ecosistemas cercanos a la costa.
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