Fuxianhuiid ventral nerve cord and early nervous system evolution in Panarthropoda
| Autor: | Xi-guang Zhang, George Boyan, Yu Liu, Nicholas J. Butterfield, Tian Lan, Jin-bo Hou, Javier Ortega-Hernández, Jie Yang |
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| Rok vydání: | 2016 |
| Předmět: |
0301 basic medicine
Nervous system China Nerve root Nervous System 03 medical and health sciences Species Specificity Priapulida Tardigrada medicine Animals Onychophora Phylogeny Panarthropoda Multidisciplinary biology Fossils Biological Sciences biology.organism_classification Biological Evolution Chengjiangocaris Ganglia Invertebrate 030104 developmental biology Geography medicine.anatomical_structure Ventral nerve cord Neuroscience Ecdysozoa |
| Zdroj: | Proceedings of the National Academy of Sciences. 113:2988-2993 |
| ISSN: | 1091-6490 0027-8424 |
| Popis: | Panarthropods are typified by disparate grades of neurological organization reflecting a complex evolutionary history. The fossil record offers a unique opportunity to reconstruct early character evolution of the nervous system via exceptional preservation in extinct representatives. Here we describe the neurological architecture of the ventral nerve cord (VNC) in the upper-stem group euarthropod Chengjiangocaris kunmingensis from the early Cambrian Xiaoshiba Lagerstätte (South China). The VNC of C. kunmingensis comprises a homonymous series of condensed ganglia that extend throughout the body, each associated with a pair of biramous limbs. Submillimetric preservation reveals numerous segmental and intersegmental nerve roots emerging from both sides of the VNC, which correspond topologically to the peripheral nerves of extant Priapulida and Onychophora. The fuxianhuiid VNC indicates that ancestral neurological features of Ecdysozoa persisted into derived members of stem-group Euarthropoda but were later lost in crown-group representatives. These findings illuminate the VNC ground pattern in Panarthropoda and suggest the independent secondary loss of cycloneuralian-like neurological characters in Tardigrada and Euarthropoda. |
| Databáze: | OpenAIRE |
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