Conference papers

Bermejo F., Di Paolo, E. A., Gilberto, L. G., Lunati, V., and Barrios, M. V. (2019). Efecto disruptivo generado por la reversión de las claves auditivas. XVII Reunión Nacional y VI Encuentro Internacional de la Asociación Argentina de Ciencias del Comportamiento, August 28–30, 2019, Posadas, Argentina.

Aguilera, M. and Di Paolo, E. A. (2018). Integrated information and autonomy in the thermodynamic limit. In T. Ikegami, N. Virgo, O. Witkowski, M. Oka, R. Suzuki, and H Iizuka (eds.) ALIFE 2018: The 2018 Conference on Artificial Life, MIT Press. July 23–27, 2018, Tokyo, Japan. pp. 113–120.

Bermejo F., Di Paolo E. A., Arias C. (2016). Listening to a world transformed: Perception in an inverted acoustic field. Artificial Life XV, The 15th International Conference on the Synthesis and Simulation of Living Systems, 4–8 July, 2016, Cancun, Mexico.

Hu, X-B, Liao, J-Q, Di Paolo, E. A. (2016). A simulation study on air traffic control strategies. 12th World Congress on Intelligent Control and Automation (WCICA), June 12-15, 2016, Guilin, China, IEEE, pp. 1577–1583.  DOI: 10.1109/WCICA.2016.7578538.

Bermejo F., Lunati V., Hüg M. X., Di Paolo E. A., Arias C. (2015). Reconocer figuras geométricas con un dispositivo de sustitución sensorial. XV Reunión Nacional y IV Encuentro Internacional de la Asociación Argentina de Ciencias del Comportamiento y 2º Congreso Argentino de Biología del Comportamiento. 26 – 28 August 2015, Tucumán, Argentina.

Buhrmann, T. and Di Paolo, E. A. (2014). Non-representational sensorimotor knowledge. In: del Pobil A.P., Chinellato E., Martinez-Martin E., Hallam J., Cervera E., Morales A. (eds) From Animals to Animats 13. SAB 2014. Lecture Notes in Computer Science, vol 8575, New York, Springer Verlag. pp. 21–31. https://doi.org/10.1007/978-3-319-08864-8_3.

Barandiaran, X. and Di Paolo, E. A. (2011). Modelling sensorimotor habits with neuro-robotics: A reappraisal of the habit concept in psychology, in ESCOP 2011, 17th Meeting of the European Society for Cognitive Psychology, Donostia, Spain, 29 Sept–2 Oct 2011.

Kyselo, M. and Di Paolo, E. A. (2010). Through the enactive eye – Locked-in syndrome as a challenge for embodied cognition, 10th Biannual Conference of the German Society for Cognitive Science, KogWis 2010, Potsdam, October 3-6, 2010.

Egbert, M., Barandiaran, X and Di Paolo, E. A. (2010). Behavioral metabolution: Metabolism based behavior enables new forms of adaptation and evolution Artificial Life XII, The 12th International Conference on the Synthesis and Simulation of Living Systems, 19-23 August, 2010, Odense, Denmark, pp. 213–220.

Hu, X-B, Wang, M., Leeson, M. S., Hines, E. L. and Di Paolo, E. A. (2010). A review on ripple-spreading genetic algorithms for combinatorial optimization problems, In ICCI 2010, The 9th IEEE International Conference on Cognitive Informatics, July 7–9, 2010, Tsinghua University, Beijing, China. DOI: 10.1109/COGINF.2010.5599700.

Barandiaran, X. and Di Paolo. E. A. (2010). Homeostatic plasticity in robots. 4th International Conference on Cognitive Systems. CogSys, 2010, ETH Zurich, Switzerland, Jan 27-28, 2010.

Froese, T. and Di Paolo, E. A. (2009). Toward minimally social behavior: Social psychology meets evolutionary robotics. In: Kampis G., Karsai I., Szathmáry E. (eds) Advances in Artificial Life. Darwin Meets von Neumann. ECAL 2009. Lecture Notes in Computer Science, vol 5777. Springer, Berlin, Heidelberg. pp. 426–433. https://doi.org/10.1007/978-3-642-21283-3_53.

Manicka, S. and Di Paolo, E. A. (2009). Local ultrastability in a real system based on programmable springs. In: Kampis G., Karsai I., Szathmáry E. (eds) Advances in Artificial Life. Darwin Meets von Neumann. ECAL 2009. Lecture Notes in Computer Science, vol 5777. Springer, Berlin, Heidelberg. pp. 91–98. https://doi.org/10.1007/978-3-642-21283-3_12.

Egbert, M., Di Paolo, E. A. and Barandiaran, X. (2009). Chemo-ethology of a adaptive protocell: Sensor-less sensitivity to implicit viability conditions. In: Kampis G., Karsai I., Szathmáry E. (eds) Advances in Artificial Life. Darwin Meets von Neumann. ECAL 2009. Lecture Notes in Computer Science, vol 5777. Springer, Berlin, Heidelberg. pp. 248–255. https://doi.org/10.1007/978-3-642-21283-3_31.

Hu, X-B, and Di Paolo, E., (2009). A ripple-spreading genetic algorithm for the airport gate assignment problem. IEEE Congress on Evolutionary Computation, CEC, 2009, Trondheim, Norway, 18-21 May, 2009, pp. 1857–1864. DOI: 10.1109/CEC.2009.4983167.

Grespan, L., Froese, T., Di Paolo, E. A., Seth, A., Spiers, A. & Bigge, W. (2008). Investigating the role of movement in the constitution of spatial perception using the Enactive Torch, in: E. Ruffaldi & M. Fontana (eds.), Enactive/08: Proceedings of the 5th Int. Conference on Enactive Interfaces, Pisa, Italy, 19–21 November: Edizioni ETS, pp. 105–110

Egbert, M. and Di Paolo, E. A.(2008). Mechanisms of adaptation to periodic environmental change. In M. Schlesinger, L. Berthouze, & C. Balkenius (eds). Proceedings of the Eight International Conference on Epigenetic Robotics 2008, July 30–31, Brighton, UK. Lund University Cognitive Studies, 139, Lund, Sweden. pp. 141–142.

Di Paolo, E. A. (2008). Life in time: The missing temporal dimension in autopoiesis (Abstract). In S. Bullock, J. Noble, R. A. Watson, and M. A. Bedau (Eds.) Proceedings of the 11th International Conference on Artificial Life, Alife XI, Winchester, UK, MIT Press, Cambridge, MA, p. 761.

Rohde, M. and Di Paolo, E. A. (2008). Evolutionary robotics models in the interdisciplinary study of embodied time perception (Abstract). In S. Bullock, J. Noble, R. A. Watson, and M. A. Bedau (Eds.) Proceedings of the 11th International Conference on Artificial Life, Alife XI, Winchester, UK, MIT Press, Cambridge, MA, p. 798.

Barandiaran, X. and Di Paolo, E. A. (2008). Artificial mental life (Abstract). In S. Bullock, J. Noble, R. A. Watson, and M. A. Bedau (Eds.) Proceedings of the 11th International Conference on Artificial Life, Alife XI, Winchester, UK, MIT Press, Cambridge, MA, p. 747.

Vargas, P., Di Paolo, E. A. and Husbands, P. (2008). A study of GasNets spatial embedding in a delayed response task. In S. Bullock, J. Noble, R. A. Watson, and M. A. Bedau (Eds.) Proceedings of the 11th International Conference on Artificial Life, Alife XI, Winchester, UK, MIT Press, Cambridge, MA, pp. 640–647.

Buckley, C., Fine, P. Bullock, S. and Di Paolo, E. A. (2008). Monostable controllers for adaptive behaviour. In: Asada M., Hallam J.C.T., Meyer JA., Tani J. (eds) From Animals to Animats 10. SAB 2008. Lecture Notes in Computer Science, vol 5040. Springer, Berlin, Heidelberg. pp. 103–112. Osaka, Japan, July 7-10, 2008. https://doi.org/10.1007/978-3-540-69134-1_11.

Froese, T. and Di Paolo, E. A. (2008). Stability of coordination requires mutuality of interaction in a model of embodied agents. In: Asada M., Hallam J.C.T., Meyer JA., Tani J. (eds) From Animals to Animats 10. SAB 2008. Lecture Notes in Computer Science, vol 5040. Springer, Berlin, Heidelberg. pp. 52–61. Osaka, Japan, July 7-10, 2008. https://doi.org/10.1007/978-3-540-69134-1_6.

Fernandez-Leon, J. and Di Paolo, E. A. (2008). Neural noise induces the evolution of robust behaviour by avoiding non-functional bifurcations. In: Asada M., Hallam J.C.T., Meyer JA., Tani J. (eds) From Animals to Animats 10. SAB 2008. Lecture Notes in Computer Science, vol 5040. Springer, Berlin, Heidelberg. pp. 32–41. Osaka, Japan, July 7-10, 2008. https://doi.org/10.1007/978-3-540-69134-1_4.

Iizuka, H. and Di Paolo, E. A. (2008). Extended homeostatic adaptation: Improving the link between internal and behavioural stability. IIn: Asada M., Hallam J.C.T., Meyer JA., Tani J. (eds) From Animals to Animats 10. SAB 2008. Lecture Notes in Computer Science, vol 5040. Springer, Berlin, Heidelberg. pp. 1–11. Osaka, Japan, July 7-10, 2008. http://doi.org/10.1007/978-3-540-69134-1_1.

Rohde, M. and Di Paolo, E. A. (2008). Embodiment and perceptual crossing in 2D: A comparative evolutionary robotics study. In: Asada M., Hallam J.C.T., Meyer JA., Tani J. (eds) From Animals to Animats 10. SAB 2008. Lecture Notes in Computer Science, vol 5040. Springer, Berlin, Heidelberg. Springer-Verlag, pp. 83–92. Osaka, Japan, July 7-10, 2008. https://doi.org/10.1007/978-3-540-69134-1_9.

Froese, T. and Di Paolo, E. A. (2008). An enactive approach to social cognition: Detection of social contingency or stability of interaction dynamics? In euCognition Fourth Six-Monthly Meeting, 10-11 January 2008, Venice. (Winner of best paper competition).

Hu, X-B., Di Paolo E. A. and Barnett, L. (2008). Ripple-spreading model and genetic algorithm for random complex networks: Preliminary study. In The World Congress on Computer Intelligence (WCCI2008), Hong Kong, China, 1–6 June 2008.

Hu X-B., Di Paolo E. (2008) A genetic algorithm based on complex networks theory for the management of airline route networks. In: Krasnogor N., Nicosia G., Pavone M., Pelta D. (eds) Nature Inspired Cooperative Strategies for Optimization (NICSO 2007). Studies in Computational Intelligence, vol 129. Springer, Berlin, Heidelberg. pp 495–505. https://doi.org/10.1007/978-3-540-78987-1_45.

Hu X-B., Di Paolo E. (2008) A hybrid genetic algorithm for the travelling salesman problem. In: Krasnogor N., Nicosia G., Pavone M., Pelta D. (eds) Nature Inspired Cooperative Strategies for Optimization (NICSO 2007). Studies in Computational Intelligence, vol 129. Springer, Berlin, Heidelberg. pp 357–367.
https://doi.org/10.1007/978-3-540-78987-1_32.

Di Paolo, E. A., (2007). Play, enaction and the dialectics of worldmaking in Toward a Science of Consciousness 2007, Budapest, Hungary, July 23-26, 2007.

Wood, R. and Di Paolo, E. A. (2007). New models for old questions: Evolutionary robotics and the ‘A not B’ error. In: Almeida e Costa F., Rocha L.M., Costa E., Harvey I., Coutinho A. (eds) Advances in Artificial Life. ECAL 2007. Lecture Notes in Computer Science, vol 4648. Springer, Berlin, Heidelberg. pp. 1141–1150. https://doi.org/10.1007/978-3-540-74913-4_114.

Rohde, M. and Di Paolo, E. A. (2007). Adaptation to sensory delays. An evolutionary robotics model of an empirical study. In: Almeida e Costa F., Rocha L.M., Costa E., Harvey I., Coutinho A. (eds) Advances in Artificial Life. ECAL 2007. Lecture Notes in Computer Science, vol 4648. Springer, Berlin, Heidelberg. pp. 193–202. https://doi.org/10.1007/978-3-540-74913-4_20.

Iizuka, H. and Di Paolo, E. A. (2007). Minimal agency detection of embodied agents. In: Almeida e Costa F., Rocha L.M., Costa E., Harvey I., Coutinho A. (eds) Advances in Artificial Life. ECAL 2007. Lecture Notes in Computer Science, vol 4648. Springer, Berlin, Heidelberg. pp. 485–494. https://doi.org/10.1007/978-3-540-74913-4_49.

Fine, P., Di Paolo, E. A., Izquierdo, E. (2007). Adapting to your body. In: Almeida e Costa F., Rocha L.M., Costa E., Harvey I., Coutinho A. (eds) Advances in Artificial Life. ECAL 2007. Lecture Notes in Computer Science, vol 4648. Springer, Berlin, Heidelberg. pp. 203–212. https://doi.org/10.1007/978-3-540-74913-4_21.

Dyke, J., McDonald-Gibson, J., Di Paolo, E. A. and Harvey, I. (2007). Increasing complexity can increase stability in a self-regulating ecosystems. In: Almeida e Costa F., Rocha L.M., Costa E., Harvey I., Coutinho A. (eds) Advances in Artificial Life. ECAL 2007. Lecture Notes in Computer Science, vol 4648. Springer, Berlin, Heidelberg. pp. 133–142.

Fernandez-Leon, J. and Di Paolo, E. A. (2007). Neural uncertainty and sensorimotor robustness. In: Almeida e Costa F., Rocha L.M., Costa E., Harvey I., Coutinho A. (eds) Advances in Artificial Life. ECAL 2007. Lecture Notes in Computer Science, vol 4648. Springer, Berlin, Heidelberg. pp. 786–795. https://doi.org/10.1007/978-3-540-74913-4_79.

Vargas, P., Di Paolo, E. A. and Husbands, P. (2007). Preliminary investigations on the evolvability of a non-spatial GasNet model. In: Almeida e Costa F., Rocha L.M., Costa E., Harvey I., Coutinho A. (eds) Advances in Artificial Life. ECAL 2007. Lecture Notes in Computer Science, vol 4648. Springer, Berlin, Heidelberg. pp. 966–975. https://doi.org/10.1007/978-3-540-74913-4_97.

Hu, X. and Di Paolo, E. A., (2007) An efficient genetic algorithm with uniform crossover for the multi-objective airport gate assignment problem, in 2007 IEEE Congress on Evolutionary Computation, CEC 2007, Singapore, September 25-28, 2007, pp. 55–62.

Iizuka, H., and Di Paolo, E. A., (2006). Are you interacting with me? The embodied dynamics of minimal agency detection. Last minute abstract From Animats to Animals 9 The Ninth International Conference on the Simulation of Adaptive Behavior (SAB’06) 25–29 September 2006, CNR, Roma, Italy .

Rohde, M and Di Paolo, E. A. (2006) An evolutionary robotics simulation of human minimal social interaction. Workshop on Behaviour and Mind as a Complex Adaptive System, SAB’06, Roma, Italy, 30 September 2006.

Wood, R., and Di Paolo, E. A., (2006). Learn to live with yourself: A developmental perspective on morphology and motion. Workshop on Morphology, Motion and Cognition, Alife X, 3–4 June, 2006, Bloomington, Indiana, USA.

Buehrmann, T., and Di Paolo, E. A., (2006). Biological actuators are not just springs: Investigating muscle dynamics and control signals. In: Nolfi S. et al. (eds) From Animals to Animats 9. SAB 2006. Lecture Notes in Computer Science, vol 4095. Springer, Berlin, Heidelberg. pp. 89–100. 25–29 September 2006, CNR, Roma, Italy. https://doi.org/10.1007/11840541_8.

Fine, P. A., Di Paolo, E. A., and Philippides, A. O., (2006). Spatially constrained networks and the evolution of modular control systems. In: Nolfi S. et al. (eds) From Animals to Animats 9. SAB 2006. Lecture Notes in Computer Science, vol 4095. Springer, Berlin, Heidelberg. pp. 546–557. 25–29 September 2006, CNR, Roma, Italy. https://doi.org/10.1007/11840541_45.

Rohde, M., and Di Paolo, E. A., (2006). Evolutionary robotics and perceptual supplementation: Dialogue between two minimalist approaches. AI’50. 50th Anniversary Summit of Artificial Intelligence. Monte Verita, Switzerland, 9–14 July, 2006.

Hu, X., and Di Paolo, E. A., (2006). Genetic algorithms: artificial selection via natural selection. 6th World Congress on Intelligent Control and Automation, WCICA06, DaLian, China.

Macinnes, I., and Di Paolo, E. A., (2005). The advantages of evolving perceptual cues. Active agents and their environments as dynamical systems (Activate.d) workshop at ECAL 2005.

Rohde, M. and Di Paolo, E. A., (2005). t for two. Linear synergy advances the evolution of directional pointing behaviour. In: Capcarrère M.S., Freitas A.A., Bentley P.J., Johnson C.G., Timmis J. (eds) Advances in Artificial Life. ECAL 2005. Lecture Notes in Computer Science, vol 3630. Springer, Berlin, Heidelberg. pp 262–271. https://doi.org/10.1007/11553090_27.

Izquierdo-Torres, E., and Di Paolo, E. A., (2005). Is an embodied system ever purely reactive? In: Capcarrère M.S., Freitas A.A., Bentley P.J., Johnson C.G., Timmis J. (eds) Advances in Artificial Life. ECAL 2005. Lecture Notes in Computer Science, vol 3630. Springer, Berlin, Heidelberg. pp 252–261. http://doi.org/10.1007/11553090_26.

Vickerstaff, R. J., and Di Paolo, E. A., (2005). An evolved agent performing efficient path integration based homing and search. In: Capcarrère M.S., Freitas A.A., Bentley P.J., Johnson C.G., Timmis J. (eds) Advances in Artificial Life. ECAL 2005. Lecture Notes in Computer Science, vol 3630. Springer, Berlin, Heidelberg. pp 221–230. https://doi.org/10.1007/11553090_23.

Macinnes, I., and Di Paolo, E. A., (2005). From the inside looking out: Self-extinguishing perceptual cues and the constructed worlds of animats. In: Capcarrère M.S., Freitas A.A., Bentley P.J., Johnson C.G., Timmis J. (eds) Advances in Artificial Life. ECAL 2005. Lecture Notes in Computer Science, vol 3630. Springer, Berlin, Heidelberg. pp 11–20. http://doi.org/10.1007/11553090_2.

Suzuki, M., Floreano, D. and Di Paolo, E. A., (2005). Constraints on body movement during visual development affect behavior of evolutionary robots. Proceedings of the International Joint Conference on Neural Networks (IJCNN) 2005, Montreal, IEEE Press. pp. 2778–2783. http://doi.org/10.1109/IJCNN.2005.1556365.

Harvey, I., Vaughan, E., and Di Paolo, E. A., (2004). Time and motion studies: The dynamics of cognition, computation and humanoid walking. In HART 2004, Fourth International Symposium on Human and Artificial Intelligence Systems: From Control to Autonomy. December 5–6, 2004, University of Fukui, Fukui, Japan.

Vaughan, E., Di Paolo, E. A. and Harvey, I., (2004). The tango of a load balancing biped. In: M. A. Armada, P. de González Santos (eds.) Climbing and Walking Robots. Springer, Berlin, Heidelberg. pp 813–823. https://doi.org/10.1007/3-540-29461-9_79. 7th International Conference on Climbing and Walking Robots, CLAWAR 2004 Madrid, September 22–24, 2004.

Buehrmann, T. and Di Paolo, E. A., (2004). Closing the loop: Evolving a model-free visually-guided robot arm. In: Pollack, Jordan B., Bedau, Mark, Husbands, Phil, Ikegami, Takashi and Watson, Richard A. , Pollack, Jordan B., Bedau, Mark, Husbands, Phil, Ikegami, Takashi and Watson, Richard A. (eds.) Artificial Life IX: Proceedings of the Ninth International Conference on the Simulation and Synthesis of Living Systems, MIT Press. pp. 63–68. (lower quality pdf with page numbers).

Fernando, C. and Di Paolo, E. A. (2004). The Chemoton: A model for the origin of long RNA templates. In: Pollack, Jordan B., Bedau, Mark, Husbands, Phil, Ikegami, Takashi and Watson, Richard A. , Pollack, Jordan B., Bedau, Mark, Husbands, Phil, Ikegami, Takashi and Watson, Richard A. (eds.) Artificial Life IX: Proceedings of the Ninth International Conference on the Simulation and Synthesis of Living Systems, MIT Press. pp. 1–8. (lower quality pdf with page numbers).

Macinnes, I. and Di Paolo, E. A., (2004). Crawling out of the simulation: Evolving real robot morphologies using cheap, reusable modules. In: Pollack, Jordan B., Bedau, Mark, Husbands, Phil, Ikegami, Takashi and Watson, Richard A. , Pollack, Jordan B., Bedau, Mark, Husbands, Phil, Ikegami, Takashi and Watson, Richard A. (eds.) Artificial Life IX: Proceedings of the Ninth International Conference on the Simulation and Synthesis of Living Systems, MIT Press. pp. 94–99. (lower quality pdf with page numbers).

Vaughan, E., Di Paolo, E. A. and Harvey, I., (2004). The evolution of control and adaptation in a 3D powered passive dynamic walker. In: Pollack, Jordan B., Bedau, Mark, Husbands, Phil, Ikegami, Takashi and Watson, Richard A. , Pollack, Jordan B., Bedau, Mark, Husbands, Phil, Ikegami, Takashi and Watson, Richard A. (eds.) Artificial Life IX: Proceedings of the Ninth International Conference on the Simulation and Synthesis of Living Systems, MIT Press. pp. 139–145. (lower quality pdf with page numbers).

Di Paolo, E. A., (2002). Evolving spike-timing dependent plasticity for robot control. EPSRC/BBSRC International Workshop: Biologically-inspired Robotics, The Legacy of W. Grey Walter, WGW’2002. HP Labs, Bristol, 14 – 16 August 2002.

Di Paolo, E. A., (2002). Fast homeostatic oscillators induce radical robustness in robot performance. B. Hallam et al. (eds.) From animals to animats 7: Proceedings of the Seventh International Conference on Simulation of Adaptive Behavior, SAB’2002, MIT Press, pp. 303–304.

Di Paolo, E. A., (2001). Artificial life and historical processes. In: Kelemen J., Sosík P. (eds) Advances in Artificial Life. ECAL 2001. Lecture Notes in Computer Science, vol 2159. Springer, Berlin, Heidelberg. pp. 649–658. https://doi.org/10.1007/3-540-44811-X_75.

Di Paolo, E. A., (2000). Homeostatic adaptation to inversion of the visual field and other sensorimotor disruptions. From Animals to Animals, Proc. of the Sixth International Conference on the Simulation of Adaptive Behavior, SAB’2000, Paris, J-A. Meyer, A. Berthoz, D. Floreano, H. Roitblat and S W. Wilson (eds), MIT Press, pp. 440–449

Di Paolo, E. A., (2000). Searching for rhythms in asynchronous Boolean Networks.  Artificial Life VII: The Seventh International Conference on the Simulation and Synthesis of Living Systems, Reed College, Portland, Oregon, USA, 1–6 August, 2000. pp. 73–80.

Di Paolo, E. A., Noble, J. & Bullock, S. (2000). Simulation models as opaque thought experiments.  Artificial Life VII: The Seventh International Conference on the Simulation and Synthesis of Living Systems, Reed College, Portland, Oregon, USA, 1–6 August, 2000. pp. 497–506. (lower quality pdf with page numbers).

Di Paolo E. A. (1999). A little more than kind and less than kin: The unwarranted use of kin selection in spatial models of communication. In: Floreano D., Nicoud JD., Mondada F. (eds) Advances in Artificial Life. ECAL 1999. Lecture Notes in Computer Science, vol 1674. Springer, Berlin, Heidelberg. pp 504–513. https://doi.org/10.1007/3-540-48304-7_69.

Di Paolo, E. A., (1998). Behavioural coordination in acoustically coupled agents. In Proceedings of  ICANN’98 8th International Conference on Artificial Neural Networks, Skoevde, Sweden, 2-4 September 1998, Nicklasson, L, Boden, M. and Ziemke, T. (eds.) Springer, London. pp. 1097–1102. https://doi.org/10.1007/978-1-4471-1599-1_172.

Di Paolo, E. A., (1998). Assessing the role of social development in the evolution of cooperation R. Pfeifer et al. (eds) From Animats to Animals, Proceedings of the Fifth International Conference of the Society for Adaptive Behavior, (SAB98), Zürich, Switzerland, 17-21 August, 1998, Cambridge, MA: MIT Press, pp. 453–458.

Di Paolo, E. A., (1997). Social coordination and spatial organization: Steps towards the evolution of communication Proceedings of the 4th European Conference on Artificial Life, ECAL97, Phil Husbands and Inman Harvey (eds.), Cambridge, MA: MIT Press/Bradford Books. pp. 464–475.