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On the Independent Origins of Complex Brains and Neurons
Open accessAbstract
Analysis of the origin and evolution of neurons is crucial for revealing principles of organization of neural circuits with unexpected implications for genomic sciences, biomedical applications and regenerative medicine. This article presents an overview of some controversial ideas about the origin and evolution of neurons and nervous systems, focusing on the independent origin of complex brains and possible independent origins of neurons. First, earlier hypotheses related to the origin of neurons are summarized. Second, the diversity of nervous systems and convergent evolution of complex brains in relation to current views about animal phylogeny is discussed. Third, the lineages of molluscs and basal metazoans are used as illustrated examples of multiple origins of complex brains and neurons. Finally, a hypothesis about the independent origin of complex brains, centralized nervous systems and neurons is outlined. Injury-associated mechanisms leading to secretion of signal peptides (and related molecules) can be considered as evolutionary predecessors of inter-neuronal signaling and the major factors in the appearance of neurons in the first place.
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“The first nervous systems are suggested to be primarily peptidergic in nature 7 .”
From The ctenophore genome and the evolutionary origins of neural systems (2014) · cites this paper as [7]
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The ctenophore genome and the evolutionary origins of neural systems
Moroz, L. L., Kocot, K. M., Citarella, M. R., Dosung, S., Norekian, T. P., Povolotskaya, I. S., Grigorenko, A. P., Dailey, C., Berezikov, E., Buckley, K. M., et al. (2014) · Nature · doi:10.1038/nature13400 · Cited by 716
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Self-citationInvertebrate neurophylogeny: suggested terms and definitions for a neuroanatomical glossary
Richter, S., Loesel, R., Purschke, G., Schmidt‐Rhaesa, A., Scholtz, G., Stach, T., Vogt, L., Wanninger, A., Brenneis, G., Döring, C., et al. (2010) · Frontiers in Zoology · doi:10.1186/1742-9994-7-29 · Cited by 334
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Metadata
- Authors
- Moroz, L. L.
- Affiliations
- University of Florida (US)
- Corresponding author
- Moroz, Leonid L.
- ORCID
- Moroz, Leonid L.
- Venue
- Brain, Behavior and Evolution
- Publisher
- S. Karger AG
- Published
- 2009
- Volume
- 74
- Issue
- 3
- Pages
- 177-190
- ISSN
- 0006-8977 (ISSN-L)
- 1421-9743
- PMC
- PMC2855278
- OpenAlex
- W2073642997
- Cited by
- 209
- References
- 83
- Citations by year
- 2026: 9 · 2025: 11 · 2024: 18 · 2023: 12 · 2022: 7 · 2021: 20 · 2020: 11 · 2019: 11 · 2018: 11 · 2017: 9 · 2016: 11 · 2015: 33 · 2014: 11 · 2013: 13 · 2012: 10
- FWCI
- 0.75
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- Brain Behavior and Evolution (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Funders
- National Science Foundation (0744649)
- Brain Research Foundation
- McKnight Foundation
- Evelyn F. McKnight Brain Research Foundation
- National Institutes of Health
- National Institute of Neurological Disorders and Stroke (1R01NS06076)
- National Center for Research Resources (R21RR025699)
- Topics
- Life Sciences › Agricultural and Biological Sciences › Animal Science and Zoology › Marine Invertebrate Physiology and Ecology
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Developmental Biology and Gene Regulation
- Life Sciences › Neuroscience › Cellular and Molecular Neuroscience › Neurobiology and Insect Physiology Research
- Keywords
- nervous system evolution, Mollusca, basal metazoans, animal phylogeny, neural circuit organization
- MeSH terms
- Animals, Brain, Biological Evolution, Models, Biological, Mollusca, Neurons
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