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Especies en peligro de extinción: revisión de la ley provocada por el callejón sin salida de tellico
Science (New York, N.Y.)
|June 24, 1977
Resumen
La vida es vida La vida es vida
Área de la Ciencia:
- La historia evolutiva de la Tierra.
- Paleontología Paleontología.
- Escala de tiempo geológico.
Sus antecedentes:
- La historia de la Tierra es vasta, por lo que las líneas de tiempo evolutivas son difíciles de comprender.
- Un año metafórico simplifica la inmensa escala de tiempo del desarrollo de la vida.
Objetivo del estudio:
- Proporcionar una analogía relatable para la evolución de la vida en la Tierra.
- Para contextualizar el momento de los principales eventos evolutivos y la aparición humana.
Principales métodos:
- Utilizando una analogía de "un año" para representar los 4.500 millones de años de historia de la Tierra.
- Mapear eventos clave como el origen de la vida, los registros fósiles, el dominio de los dinosaurios, la aparición de mamíferos y la aparición humana en fechas específicas dentro de este año.
Principales resultados:
- Las condiciones de vida aparecen a finales de junio; los fósiles más antiguos a mediados de octubre.
- Los dinosaurios dominan a mediados de diciembre; los mamíferos aparecen justo antes de Navidad.
- Los seres humanos emergen en la víspera de Año Nuevo, con el impacto humano reciente que ocurre en los últimos segundos.
Conclusiones:
- La historia humana, especialmente los eventos recientes de extinción, representa una fracción infinitesimalmente pequeña del tiempo evolutivo.
- Las tasas actuales de extinción de especies impulsadas por los humanos no tienen precedentes en la historia evolutiva.
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