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Alta incidencia del patrón de variación geográfica "salto de rana" en las aves andinas: implicaciones para el proceso
Science (New York, N.Y.)
|April 13, 1984
Resumen
Las especies de aves andinas exhiben un patrón de color único de "salto de rana", donde las poblaciones similares están separadas por distintos grupos intermedios. Esta variación geográfica sugiere un elemento aleatorio en la evolución de las aves.
Área de la Ciencia:
- Ornitología Ornitología.
- Biología evolutiva Biología evolutiva.
- La biogeografía es la biogeografía.
Sus antecedentes:
- La variación geográfica en la coloración de las aves es común, pero un patrón específico llamado "leapfrog" es especialmente frecuente en los Andes.
- El patrón de salto de rana implica poblaciones de aspecto similar separadas por distintas poblaciones intermedias de la misma especie.
Objetivo del estudio:
- Describir y cuantificar la prevalencia del patrón de color de la rana saltadora en las especies de aves andinas.
- Investigar los factores evolutivos y geográficos que contribuyen a este patrón único.
Principales métodos:
- Análisis de la variación geográfica en los patrones de color a través de las especies y superespecies de aves andinas.
- Evaluación estadística de la ocurrencia y distribución del patrón de la rana saltadora.
Principales resultados:
- Aproximadamente el 21% de las especies de aves andinas y superespecies con múltiples poblaciones diferenciadas muestran el patrón de la rana saltadora.
- Se observaron múltiples casos de patrones de color que se saltaban dentro de varias especies.
- La distribución geográfica de los taxones que exhiben el patrón de la rana saltadora muestra una falta de concordancia, lo que indica aleatoriedad.
Conclusiones:
- El patrón de salto de rana es un fenómeno significativo en la biogeografía aviar andina.
- La diferenciación fenotípica en estas aves parece implicar un fuerte componente aleatorio con respecto a la dirección, la geografía y el momento de los cambios evolutivos.
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