BEHAVIORAL DECEPTION

Theoretical models predict that deception should occur even in stable signalling systems. Assessment of the prevalence of deception and its importance has, however, been hampered by the lack of a rigorous defin ition of what constitutes deception and by the anecdotal nature of muc h of the literature, For an interaction to qualify as deception, the r eceiver of the 'deceptive' signal must incur a cost. While this cost i s often clear in interspecific interactions, it is more difficult to e valuate in interactions between members of the same species. A systema tic approach to the study of deception, including the use of experimen tal techniques to elicit deceptive behaviour, is now required. Such an approach may enable us to address a crucial question in social evolut ion - whether animals are capable of manipulating the minds of others, or merely their behaviour.