{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,16]],"date-time":"2025-12-16T12:05:18Z","timestamp":1765886718699},"reference-count":15,"publisher":"MIT Press - Journals","issue":"1","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Artificial Life"],"published-print":{"date-parts":[[1999,1]]},"abstract":"<jats:p>An artificial life entertainment-software product called Creatures was released in Europe in late 1996 and in the United States and Japan in mid-1997. When installed on a domestic computer (PC or Macintosh), each Creatures CD-ROM creates a virtual world in which autonomous software agents exist. The agents, known as \u201cnorns,\u201d interact with the human user, with each other, and with objects in their virtual world. Each norn coordinates perception and action via its own modular recurrent neural network: Each network has Hebbian learning, plus diffuse modulation of activity via a \u201chormonal\u201d system that is part of that norn's \u201cbiochemistry.\u201d Details of each norn's neural network and biochemistry are genetically specified, and norns can breed via sexual reproduction. In the reproduction process, genetic material may be mutated and may also be subjected to \u201cgene duplications\u201d that enable potentially unlimited increases in complexity of the norns' design. Over 500,000 Creatures CD-ROMS have now been sold. As each installed copy of Creatures can support 5 to 10 simultaneously existing individual norns, it seems reasonable to estimate that there are up to 5 million norns existing in the \u201ccyberspace\u201d provided by the global Creatures user community. Continued growth of the global norn population, to figures measured in tens of millions, is quite likely. Although a commercial product, the Creatures digital ecosystem should be of interest to artificial life scientists: There are obvious parallels with Yaeger's Poly World and Ray's Net Tierra systems. This article provides a detailed discussion of the links between the artificial life literature and the technology used in Creatures and includes anecdotal discussion of the \u201cdigital naturalism\u201d witnessed on the many independent websites maintained by Creatures enthusiasts.<\/jats:p>","DOI":"10.1162\/106454699568683","type":"journal-article","created":{"date-parts":[[2002,7,27]],"date-time":"2002-07-27T11:55:01Z","timestamp":1027770901000},"page":"77-93","source":"Crossref","is-referenced-by-count":20,"title":["The<i>Creatures<\/i>Global Digital Ecosystem"],"prefix":"10.1162","volume":"5","author":[{"given":"Dave","family":"Cliff","sequence":"first","affiliation":[{"name":"Artificial Intelligence Laboratory Massachusetts Institute of Technology Cambridge, MA 02139"}]},{"given":"Stephen","family":"Grand","sequence":"additional","affiliation":[{"name":"Cyber Life Technology Ltd Quayside, Bridge Street Cambridge, CB5 8AB U.K."}]}],"member":"281","reference":[{"key":"p_6","doi-asserted-by":"publisher","DOI":"10.1177\/105971239500300405"},{"key":"p_7","doi-asserted-by":"publisher","DOI":"10.1162\/artl.1997.3.4.261"},{"key":"p_14","doi-asserted-by":"publisher","DOI":"10.1523\/JNEUROSCI.15-11-07653.1995"},{"key":"p_15","doi-asserted-by":"crossref","first-page":"2395","DOI":"10.1242\/jeb.199.11.2395","volume":"199","author":"Elphick M. R.","year":"1996","journal-title":"Journal of Experimental Biology"},{"key":"p_19","doi-asserted-by":"publisher","DOI":"10.1023\/A:1010042522104"},{"key":"p_22","first-page":"495","volume":"1","author":"Hinton G.","year":"1987","journal-title":"Complex Systems"},{"key":"p_27","doi-asserted-by":"publisher","DOI":"10.1177\/105971239300200203"},{"key":"p_28","doi-asserted-by":"publisher","DOI":"10.1145\/219717.219808"},{"key":"p_29","doi-asserted-by":"publisher","DOI":"10.1016\/S0921-8890(96)00034-6"},{"key":"p_31","doi-asserted-by":"publisher","DOI":"10.1162\/evco.1996.4.3.213"},{"key":"p_39","doi-asserted-by":"publisher","DOI":"10.1162\/artl.1993.1.179"},{"key":"p_45","doi-asserted-by":"publisher","DOI":"10.1162\/artl.1994.1.4.353"},{"key":"p_48","doi-asserted-by":"publisher","DOI":"10.1162\/artl.1994.1.4.327"},{"key":"p_49","doi-asserted-by":"publisher","DOI":"10.1177\/105971239300200102"},{"key":"p_51","first-page":"1","volume":"1","author":"Van Valen L.","year":"1973","journal-title":"Evolutionary Theory"}],"container-title":["Artificial Life"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mitpressjournals.org\/doi\/pdf\/10.1162\/106454699568683","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,5,26]],"date-time":"2021-05-26T07:40:17Z","timestamp":1622014817000},"score":1,"resource":{"primary":{"URL":"https:\/\/direct.mit.edu\/artl\/article\/5\/1\/77-93\/2314"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1999,1]]},"references-count":15,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1999,1]]}},"alternative-id":["10.1162\/106454699568683"],"URL":"https:\/\/doi.org\/10.1162\/106454699568683","relation":{},"ISSN":["1064-5462","1530-9185"],"issn-type":[{"value":"1064-5462","type":"print"},{"value":"1530-9185","type":"electronic"}],"subject":[],"published":{"date-parts":[[1999,1]]}}}