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Polimorfismo y variación geográfica en el comportamiento de alimentación de la serpiente de jarretera Thamnophis
Science (New York, N.Y.)
|August 12, 1977
Resumen
La variación geográfica en las serpientes de jarretera occidentales (Thamnophis elegans) muestra que las poblaciones del interior rechazan las babosas, mientras que las poblaciones costeras las consumen fácilmente. Esta diferencia en la dieta es específica de las babosas, no de los anuranos.
Área de la Ciencia:
- Ecología del comportamiento ecología del comportamiento.
- Zoología Zoología Zoología.
- Herpetología herpetología.
Sus antecedentes:
- La variación geográfica en los comportamientos de utilización de recursos es crucial para la teoría ecológica.
- Dicha variación de comportamiento está mal documentada en muchas especies.
- La serpiente de jarretera occidental (Thamnophis elegans) exhibe diferencias geográficas en el comportamiento de alimentación.
Objetivo del estudio:
- Para investigar la variación geográfica en el comportamiento de alimentación de la serpiente de liga occidental.
- Para determinar si esta variación se extiende a diferentes tipos de presas (cercas y anuranos).
Principales métodos:
- Estudios observacionales sobre serpientes de jarretera occidentales recién nacidas y ingenuas de las localidades costeras e interiores de California.
- Evaluación de la preferencia de la presa, centrándose específicamente en las babosas y los anuranos.
Principales resultados:
- Se observó una variación geográfica significativa en la propensión de las serpientes de jarretera occidentales a atacar a las babosas.
- Las serpientes ingenuas de las localidades del interior de California se negaron en gran medida a comer babosas.
- Las serpientes ingenuas de las localidades costeras de California demostraron una alta propensión a comer babosas.
- No se encontró variación geográfica o polimorfismo en la propensión a comer anuranos; ambas poblaciones los consumieron de manera consistente.
Conclusiones:
- La serpiente de jarretera occidental exhibe una clara variación geográfica en el comportamiento de comer babosas, con poblaciones costeras que son devoradoras de babosas y poblaciones del interior que son rechazadoras de babosas.
- Esta variación de comportamiento es específica de la presa, lo que pone de relieve la compleja interacción entre la geografía, el comportamiento y la dieta en la adaptación.
- Las implicaciones ecológicas y evolutivas de esta especialización alimentaria localizada merecen una mayor investigación.
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