Europhys. Lett.
Volume 74, Number 6, June 2006
Page(s) 1095 - 1101
Section Interdisciplinary physics and related areas of science and technology
Published online 26 May 2006
Europhys. Lett., 74 (6), pp. 1095-1101 (2006)
DOI: 10.1209/epl/i2005-10596-9

Long-term correlations in the surface behavior of dolphins

R. Ferrer i Cancho1 and D. Lusseau2

1  Dipartimento di Fisica, Università "La Sapienza" - Piazzale A. Moro 5 00185 Roma, Italy
2  University of Aberdeen, School of Biological Sciences - Lighthouse Field Station George St. Cromarty, Ross-shire, IV11 8YJ, Scotland, UK

received 17 August 2005; accepted in final form 26 April 2006
published online 26 May 2006

Here we study the sequences of surface behavioral patterns of dolphins (Tursiops sp.) and find long-term correlations. We show that the long-term correlations are not of a trivial nature, i.e. they cannot be explained by the repetition of the same surface behavior many times in a row. Our findings suggest that dolphins have a long collective memory extending back at least to the 7-th past behavior. As far as we know, this is the first evidence of long-term correlations in the behavior of a non-human species.

87.23.Ge - Dynamics of social systems.
89.70.+c - Information theory and communication theory.
87.53.Wz - Monte Carlo applications.

© EDP Sciences 2006