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La extinción no aleatoria y la pérdida de la historia evolutiva
A Purvis1, P M Agapow, J L Gittleman
1Department of Biology, Imperial College, Silwood Park, Ascot SL5 7PY, UK. a.purvis@ic.ac.uk
Science (New York, N.Y.)
|April 15, 2000
Resumen
Las amenazas de extinción agrupadas ponen en peligro más géneros que eventos aleatorios, arriesgando una pérdida significativa de biodiversidad y historia evolutiva, particularmente en mamíferos y aves.
Área de la Ciencia:
- Biología evolutiva Biología evolutiva.
- La ciencia de la conservación es la ciencia de la conservación.
- Los estudios de biodiversidad incluyen estudios de biodiversidad.
Sus antecedentes:
- Las jerarquías filogenéticas sugieren que las extinciones aleatorias tienen un impacto mínimo en los taxones más altos y en la historia evolutiva.
- Los riesgos actuales de extinción no están distribuidos al azar en el árbol de la vida.
Objetivo del estudio:
- Investigar las implicaciones de las amenazas de extinción no aleatorias y agrupadas en la pérdida de biodiversidad.
- Cuantificar el riesgo adicional para los géneros de aves y mamíferos debido a las amenazas agrupadas.
Principales métodos:
- Análisis de los patrones de riesgo de extinción a través de los árboles filogenéticos.
- Comparación de géneros amenazados bajo escenarios de extinción aleatorios versus agrupados.
Principales resultados:
- Las amenazas de extinción agrupadas aumentan significativamente el número de géneros en riesgo.
- Se identifican 120 géneros adicionales de aves y mamíferos como en riesgo en comparación con las predicciones de extinción aleatoria.
- La pérdida proyectada de la historia evolutiva de los mamíferos es sustancial, comparable a la pérdida de todo un filo.
Conclusiones:
- La naturaleza no aleatoria de las amenazas actuales de extinción plantea un grave riesgo para la biodiversidad.
- Los esfuerzos de conservación deben considerar el agrupamiento filogenético de las amenazas para preservar efectivamente la historia evolutiva.
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