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Las tasas de evolución: efectos del tiempo y la escala temporal
Science (New York, N.Y.)
|October 14, 1983
Resumen
Las tasas de evolución morfológica parecen más lentas en escalas de tiempo más largas debido a los artefactos de medición. El ajuste por la longitud del intervalo de tiempo es crucial para comparaciones precisas de las tasas evolutivas.
Área de la Ciencia:
- Biología evolutiva Biología evolutiva.
- Paleontología Paleontología.
- Biología del desarrollo Biología del desarrollo.
Sus antecedentes:
- Las tasas de evolución morfológica a menudo se miden en diversas escalas de tiempo, desde experimentos de laboratorio hasta el registro fósil.
- Las tasas evolutivas observadas pueden variar dependiendo de la duración del intervalo de tiempo estudiado.
Objetivo del estudio:
- Investigar la relación entre el intervalo de tiempo medido y las tasas documentadas de evolución morfológica.
- Identificar y explicar las razones artificiales de la relación inversa observada entre la tasa evolutiva y el intervalo de tiempo.
Principales métodos:
- Análisis de datos de experimentos de selección de laboratorio.
- Examen de los acontecimientos históricos de colonización.
- Revisión de los datos del registro fósil.
Principales resultados:
- Se encontró una relación inversa consistente entre la tasa medida de evolución morfológica y el intervalo de tiempo.
- Esta relación inversa se atribuye a la comparación de la variación morfológica limitada durante períodos prolongados y los efectos de la mediación temporal.
- Las tasas medidas en diferentes escalas de tiempo requieren escalar con la longitud del intervalo para una comparación válida.
Conclusiones:
- La relación inversa observada entre la tasa evolutiva y el intervalo de tiempo es un artefacto, no un fenómeno biológico.
- La comparación precisa de las tasas de evolución morfológica requiere medidas de escala por la longitud del intervalo de tiempo.
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