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Evidencia molecular de que los protistas de los mixozoos son metazoos
J F Smothers1, C D von Dohlen, L H Smith
1Department of Biological Sciences, Idaho State University, Pocatello 83209.
Science (New York, N.Y.)
|September 16, 1994
Resumen
Se aclaran los orígenes evolutivos de los Myxozoa, debatidos durante mucho tiempo. Los análisis filogenéticos revelan que estos parásitos están estrechamente relacionados con los animales bilaterales, lo que sugiere que son metazoos, no protozoos.
Área de la Ciencia:
- Biología evolutiva Biología evolutiva.
- Parasitología Parasitología.
- Filogenia molecular La filogenia molecular es la filogenia de las moléculas.
Sus antecedentes:
- La clasificación de los Myxozoa, parásitos obligados, ha sido debatida históricamente.
- Si bien exhiben características similares a las de los protozoos, aspectos de su desarrollo y forma sugieren vínculos metazoos.
Objetivo del estudio:
- Investigar los orígenes evolutivos y la ubicación filogenética de los Myxozoa.
- Para determinar si los Myxozoa pertenecen a linajes de protozoos o metazoos.
Principales métodos:
- Análisis filogenéticos utilizando secuencias de ARN ribosomal 18S.
- Aplicación de parsimonia, distancia y métodos de probabilidad máxima.
Principales resultados:
- Los análisis filogenéticos apoyan fuertemente una estrecha relación entre Myxozoa y los animales bilaterales.
- La evidencia indica que los Myxozoa se derivan de los ancestros de los metazoos.
Conclusiones:
- Los mixozoos deberían ser reclasificados de un conjunto de protozoos a un filo de metazoos.
- Este hallazgo resuelve una pregunta de larga data en la evolución del protistán y el metazoario.
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