Evolutionary Ecology

, Volume 5, Issue 3, pp 300–309

Tit-For-Tat in guppies (Poecilia reticulata): the relative nature of cooperation and defection during predator inspection

  • Lee A. Dugatkin
  • Michael Alfieri

DOI: 10.1007/BF02214234

Cite this article as:
Dugatkin, L.A. & Alfieri, M. Evol Ecol (1991) 5: 300. doi:10.1007/BF02214234


The introduction of game-theoretical thinking into evolutionary biology has laid the groundwork for a heuristic view of animal behaviour in which individuals employ ‘strategies’ — rules that instruct them how to behave in a given circumstance to maximize relative fitness. Axelrod and Hamilton (1981) found that a strategy called Tit-For-Tat (TFT) is one robust cooperative solution to the iterated Prisoner's Dilemma game. There exists, however, little empirical evidence that animals employ TFT. Predator inspection in fish provides one ecological context in which to examine the use of the TFT strategy.

Here we describe a study in which guppies were tested in multiple predator inspection trials. An individual was tested with its mirror images as well as a series of live conspecifics. Results indicate that guppies are capable of recognizing and remembering their partner's behaviour and seem to employ TFT-like strategies over the course of many inspection visits. In addition, significant differences exist between individuals in the degree to which they will inspect a predator, suggesting that ‘cooperator’ and ‘defector’ may be relative terms rather than discrete categories of behaviour.


Game theoryTit-For-Tatpredator inspectionguppy

Copyright information

© Chapman and Hall Ltd 1991

Authors and Affiliations

  • Lee A. Dugatkin
    • 1
  • Michael Alfieri
    • 1
  1. 1.Department of BiologyState University of New York at BinghamtonBinghamtonUSA