Las cavidades intracraneanas son unas estructuras muy conservativas, y no son diferentes en el linaje de los cocodrilos. Sin embargo, a partir de una variada base de datos, se han descrito varias diferencias en las cavidades en los distintos linajes que componen el grupo.
Además, se han realizado medidas lineales y volumétricas de estas cavidades para estimar las capacidades neurosensoriales de estos animales, comparándolas con las observadas mediante estudios etológicos y citológicos para comprobar su efectividad, de cara a extrapolarlos a los taxones fósiles.
Aquí el resumen:
Eusuchia is the only extant lineage of Crocodylomorpha, spanning 129 million years from its origin in the Early Cretaceous to present day. Eusuchian remains are common in numerous Mesozoic and Cenozoic fossil sites across the world. However, the structure of their inner skull cavities remains poorly known. The basal eusuchians from Lo Hueco (Late Cretaceous, Cuenca, Spain) are noteworthy because of their abundance and exquisite state of preservation. The skull of several specimens from this site and of various extant crocodylians representing major lineages were CT-scanned and their brain and pneumatic cavities were 3D reconstructed and analysed in order to assess sensory and cognitive capabilities. The results show that the inner skull cavities of eusuchians are conservative structures. Those of extant taxa are very similar to those of basal members of the group. However, there are a few characters that appear to have varied during the course of evolution, such as the shape of the caudodorsal surface of the cerebrum, the relative size of the intertympanic diverticula and the relative length of the median pharyngeal sinus. Our results also suggest that the neurosensory and cognitive capabilities of extant crocodylians, including good olfactory and visual abilities, and a specialization for low-frequency hearing, were already present in early members of Eusuchia.
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Más información:
- Referencia: Serrano-Martínez, A., Knoll, F., Ortega, F. 2019. Evolution of the inner skull cavities in Eusuchia. XVII Annual Meeting of the European Association of Vertebrate Paleontologists, Abstract Book, 79.
- Imagen: Alejandro Serrano, durante su charla.
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