--- abstract: |- Much research has been dedicated recently to applying genetic algorithms to populations of neural networks. However, while in real organisms the inherited genotype maps in complex ways into the resulting phenotype, in most of this research the development process that creates the individual phenotype is ignored. In this paper we present a model of neural development which includes cell division and cell migration in addition to axonal growth and branching. This reflects, in a very simplified way, what happens in the ontogeny of real organisms. The development process of our artificial organisms shows successive phases of functional differentiation and specialization. In addition, we find that mutations that affect different phases of development have very different evolutionary consequences. A single change in the early stages of cell division/migration can have huge effects on the phenotype while changes in later stages have usually a less drammatic impact. Sometimes changes that affect the first developental stages may be retained producing sudden changes in evolutionary history. altloc: [] chapter: ~ commentary: ~ commref: ~ confdates: ~ conference: ~ confloc: ~ contact_email: ~ creators_id: [] creators_name: - family: Cangelosi given: Angelo honourific: '' lineage: '' - family: Parisi given: Domenico honourific: '' lineage: '' - family: Nolfi given: Stefano honourific: '' lineage: '' date: 1994 date_type: published datestamp: 2002-01-11 department: ~ dir: disk0/00/00/20/25 edit_lock_since: ~ edit_lock_until: ~ edit_lock_user: ~ editors_id: [] editors_name: [] eprint_status: archive eprintid: 2025 fileinfo: /style/images/fileicons/application_pdf.png;/2025/3/cangelosi%2Dmigration%2Dncns94.pdf full_text_status: public importid: ~ institution: ~ isbn: ~ ispublished: pub issn: ~ item_issues_comment: [] item_issues_count: 0 item_issues_description: [] item_issues_id: [] item_issues_reported_by: [] item_issues_resolved_by: [] item_issues_status: [] item_issues_timestamp: [] item_issues_type: [] keywords: 'neural networks, artificial life, genotype-phenotype mapping, modularity, neural development' lastmod: 2011-03-11 08:54:52 latitude: ~ longitude: ~ metadata_visibility: show note: ~ number: 4 pagerange: ~ pubdom: FALSE publication: 'Network: Computation in Neural Systems' publisher: ~ refereed: TRUE referencetext: |- Belew R K 1993 Interposing an ontogenetic model between genetic algorithms and neural networks Advances in Neural Information Processing (NIPS5) ed J Cowan (San Mateo, CA: Morgan Kaufmann) Cecconi F and Parisi D 1993 Neural networks with motivational units From Animals to Animats 2: Proceedings Second Intl. 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(Hillsdale, NJ: Erlbaum) Yao X 1993 Evolutionary artificial neural networks International Journal of Neural Systems 4 203-222 relation_type: [] relation_uri: [] reportno: ~ rev_number: 12 series: ~ source: ~ status_changed: 2007-09-12 16:42:31 subjects: - bio-evo - comp-neuro-sci - comp-sci-art-intel - comp-sci-neural-nets - evol-psy succeeds: ~ suggestions: ~ sword_depositor: ~ sword_slug: ~ thesistype: ~ title: Cell division and migration in a 'genotype' for neural networks type: journale userid: 24 volume: 5