{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,2]],"date-time":"2025-10-02T07:34:36Z","timestamp":1759390476631,"version":"3.44.0"},"reference-count":44,"publisher":"MIT Press","issue":"2","content-domain":{"domain":["direct.mit.edu"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2025,5,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:p>Central to the Artificial Life endeavor is the creation of artificial systems that spontaneously generate properties found in the living world, such as autopoiesis, self-replication, evolution, and open-endedness. Though numerous models and paradigms have been proposed, cellular automata (CA) have taken a very important place in the field, notably because they enable the study of phenomena like self-reproduction and autopoiesis. Continuous CA like Lenia have been shown to produce lifelike patterns reminiscent, from both aesthetic and ontological points of view, of biological organisms we call \u201ccreatures.\u201d We propose Flow-Lenia, a mass conservative extension of Lenia. We present experiments demonstrating its effectiveness in generating spatially localized patterns with complex behaviors and show that the update rule parameters can be optimized to generate complex creatures showing behaviors of interest. Furthermore, we show that Flow-Lenia allows us to embed the parameters of the model, defining the properties of the emerging patterns, within its own dynamics, thus allowing for multispecies simulation. Using the evolutionary activity framework and other metrics, we shed light on the emergent evolutionary dynamics taking place in this system.<\/jats:p>","DOI":"10.1162\/artl_a_00471","type":"journal-article","created":{"date-parts":[[2025,4,29]],"date-time":"2025-04-29T09:27:52Z","timestamp":1745918872000},"page":"228-248","update-policy":"https:\/\/doi.org\/10.1162\/mitpressjournals.corrections.policy","source":"Crossref","is-referenced-by-count":1,"title":["Flow-Lenia: Emergent Evolutionary Dynamics in Mass Conservative Continuous Cellular Automata"],"prefix":"10.1162","volume":"31","author":[{"given":"Erwan","family":"Plantec","sequence":"first","affiliation":[{"name":"IT University of Copenhagen Robotics, Evolution and Artificial Life Laboratory erpl@itu.dk"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gautier","family":"Hamon","sequence":"additional","affiliation":[{"name":"Inria Center of the University of Bordeaux Flowers AI & CogSci Lab"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mayalen","family":"Etcheverry","sequence":"additional","affiliation":[{"name":"Inria Center of the University of Bordeaux Flowers AI & CogSci Lab"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bert Wang-Chak","family":"Chan","sequence":"additional","affiliation":[{"name":"Google DeepMind"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pierre-Yves","family":"Oudeyer","sequence":"additional","affiliation":[{"name":"Inria Center of the University of Bordeaux Flowers AI & CogSci Lab"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cl\u00e9ment","family":"Moulin-Frier","sequence":"additional","affiliation":[{"name":"Inria Center of the University of Bordeaux Flowers AI & CogSci Lab"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"281","published-online":{"date-parts":[[2025,5,1]]},"reference":[{"key":"2025092414361771200_bib1","doi-asserted-by":"publisher","DOI":"10.1007\/978-1-84996-217-9","volume-title":"Game of Life cellular automata","author":"Adamatzky","year":"2010"},{"key":"2025092414361771200_bib2","doi-asserted-by":"publisher","DOI":"10.48550\/arXiv.adap-org\/9405003","volume-title":"Evolutionary learning in the 2D Artificial Life system \u201cAvida.\u201d","author":"Adami","year":"1994"},{"volume-title":"Emergent microcosms","year":"2022","author":"Arbesman","key":"2025092414361771200_bib3"},{"issue":"4","key":"2025092414361771200_bib4","doi-asserted-by":"publisher","first-page":"42","DOI":"10.3390\/life10040042","article-title":"Defining lyfe in the Universe: From three privileged functions to four pillars","volume":"10","author":"Bartlett","year":"2020","journal-title":"Life"},{"key":"2025092414361771200_bib5","unstructured":"Bedau, M. 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