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La selección natural dependiente de la frecuencia en la manualidad de los peces cíclidos comedores de escamas
Science (New York, N.Y.)
|April 9, 1993
Resumen
La selección natural dependiente de la frecuencia mantiene la diversidad genética en los peces cíclidos. Los fenótipos raros de apertura de boca obtienen una ventaja depredadora, asegurando poblaciones equilibradas en el lago Tanganica.
Área de la Ciencia:
- Biología evolutiva Biología evolutiva.
- Ecología del comportamiento ecología del comportamiento.
- Ictiología Ictiología.
Sus antecedentes:
- La selección dependiente de la frecuencia es un mecanismo propuesto para mantener los polimorfismos genéticos.
- La evidencia previa de este mecanismo en poblaciones naturales ha sido limitada.
Objetivo del estudio:
- Investigar el papel de la selección natural dependiente de la frecuencia en el polimorfismo de apertura de boca de los peces cíclidos comedores de escamas.
- Para demostrar este mecanismo evolutivo en un estudio de campo.
Principales métodos:
- Estudió peces cíclidos devoradores de escamas en el lago Tanganica.
- Analizó la genética de la dirección de apertura de la boca (izquierdista vs. diestro).
- Interacciones observadas entre depredadores y presas y frecuencias de población.
Principales resultados:
- La dirección de apertura de la boca en los cíclidos está determinada genéticamente.
- Las frecuencias de población de fenotipos zurdos y diestros oscilaron alrededor de la unidad.
- El raro fenotipo exhibió un mayor éxito depredador debido al estado de alerta de la presa.
Conclusiones:
- La selección natural dependiente de la frecuencia impulsa el mantenimiento del polimorfismo de apertura de boca en esta población de cíclidos.
- La vigilancia de las presas actúa como la presión selectiva, favoreciendo las morfologías más raras.
- Este estudio proporciona evidencia de campo concluyente para la selección dependiente de la frecuencia que mantiene la diversidad genética.
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