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La caja cerebral y las mandíbulas de un 'acanthodian' devónico y el gnathostome moderno tienen sus orígenes
1Subdepartment of Evolutionary Organismal Biology, Department of Physiology and Developmental Biology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18A, SE-752 36 Uppsala, Sweden. martin.brazeau@gmail.com
Nature
|January 17, 2009
Resumen
Los primeros fósiles de vertebrados con mandíbula, acanthodians, revelan una caja cerebral primitiva en Ptomacanthus anglicus. Este descubrimiento remodela nuestra comprensión de la evolución temprana de los vertebrados y sus relaciones.
Área de la Ciencia:
- Paleontología Paleontología.
- Biología evolutiva Biología evolutiva.
- Filogenia de los vertebrados.
Sus antecedentes:
- El origen de los vertebrados con mandíbula (gnathostomes) en el Paleozoico temprano se entiende mal debido a la limitada evidencia fósil temprana.
- Los acantodios, un grupo extinto del Paleozoico, muestran una mezcla de rasgos similares a los de los tiburones y los peces óseos, lo que los convierte en clave para comprender la evolución temprana del gnathostome.
- La pobre fosilización de los endosqueletos de acanthodios ha oscurecido sus relaciones evolutivas con los vertebrados modernos.
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