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dc.contributor.authorHejnol, Andreas
dc.contributor.authorLowe, Christopher J.
dc.PublishedPhilosophical Transactions of the Royal Society of London. Biological Sciences 2015, 370(1684): 20150045eng
dc.description.abstractMolecular biology has provided a rich dataset to develop hypotheses of nervous system evolution. The startling patterning similarities between distantly related animals during the development of their central nervous system (CNS) have resulted in the hypothesis that a CNS with a single centralized medullary cord and a partitioned brain is homologous across bilaterians. However, the ability to precisely reconstruct ancestral neural architectures from molecular genetic information requires that these gene networks specifically map with particular neural anatomies. A growing body of literature representing the development of a wider range of metazoan neural architectures demonstrates that patterning gene network complexity is maintained in animals with more modest levels of neural complexity. Furthermore, a robust phylogenetic framework that provides the basis for testing the congruence of these homology hypotheses has been lacking since the advent of the field of ‘evo-devo’. Recent progress in molecular phylogenetics is refining the necessary framework to test previous homology statements that span large evolutionary distances. In this review, we describe recent advances in animal phylogeny and exemplify for two neural characters—the partitioned brain of arthropods and the ventral centralized nerve cords of annelids—a test for congruence using this framework. The sequential sister taxa at the base of Ecdysozoa and Spiralia comprise small, interstitial groups. This topology is not consistent with the hypothesis of homology of tripartitioned brain of arthropods and vertebrates as well as the ventral arthropod and rope-like ladder nervous system of annelids. There can be exquisite conservation of gene regulatory networks between distantly related groups with contrasting levels of nervous system centralization and complexity. Consequently, the utility of molecular characters to reconstruct ancestral neural organization in deep time is limited.en_US
dc.publisherThe Royal Society Publishingeng
dc.rightsAttribution CC BY 4.0eng
dc.subjectdevelopmental biologyeng
dc.subjecttaxonomy and systematicseng
dc.titleEmbracing the comparative approach: How robust phylogenies and broader developmental sampling impacts the understanding of nervous system evolutioneng
dc.typeJournal articleeng
dc.typePeer reviewedeng
dc.rights.holderCopyright 2015 The Authorseng
dc.subject.nsiVDP::Matematikk og Naturvitenskap: 400

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Attribution CC BY 4.0
Except where otherwise noted, this item's license is described as Attribution CC BY 4.0