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Los primeros cráneos del primate del Eoceno temprano Shoshonius cooperi y la dicotomía antropoide-tarsier
K C Beard1, L Krishtalka, R K Stucky
1Section of Vertebrate Paleontology, Carnegie Museum of Natural History, Pittsburgh, Pennsylvania 15213.
Nature
|January 3, 1991
Resumen
Los cráneos fósiles de primates revelan que Shoshonius cooperi está estrechamente relacionado con Tarsius, lo que desafía las ideas anteriores sobre la evolución de los primates y los orígenes de los antropoides. Este hallazgo sugiere una divergencia más temprana entre los tarsios y los antropoides de lo que se entendía anteriormente.
Área de la Ciencia:
- Paleontología de los Primates.
- Biología evolutiva Biología evolutiva.
- Anatomía comparada y anatomía comparada.
Sus antecedentes:
- La ubicación filogenética de los tarsier y los primates omomídeos extintos es crucial para comprender la evolución de los primates, especialmente los orígenes de los antropoides.
- Las hipótesis existentes sugieren que los tarsier están relacionados con los omomídeos, los antropoides o los estrepsirhinos.
Objetivo del estudio:
- Investigar las relaciones filogenéticas de los primeros primates omomídeos utilizando nuevo material craneal.
- Para poner a prueba las hipótesis que compiten con respecto a la posición evolutiva de los tarsier dentro de los primates.
Principales métodos:
- Análisis de la anatomía craneal de cuatro cráneos de Shoshonius cooperi del Eoceno temprano.
- Análisis filogenético comparativo con fósiles conocidos de omomídeos y tarsier y taxones existentes.
Principales resultados:
- La anatomía craneal de Shoshonius cooperi indica una ascendencia común más cercana con Tarsius que con los antropoides u otros omomídeos conocidos del Eoceno.
- Esta posición filogenética sugiere que si el suborden de primates Haplorhini es monofilético, los antropoides y Tarsius divergieron a principios del Eoceno.
Conclusiones:
- Shoshonius cooperi proporciona información clave sobre la evolución temprana de los primates y la divergencia de los principales grupos de primates.
- Los hallazgos requieren una revisión de la filogenia de los primates, colocando la división entre antropoides y tarsier mucho antes en el registro fósil.
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