Cooperation vs. exploitation: interactions between lycaenid (Lepidoptera: Lycaenidae) larvae and ants

Abstract

The larval stages of many lycaenid species are myrmecophilic, i.e. they are associated with ants. We revised the literature and categorized these associations as neutral (non existent, commensalistic), cooperative (mutualistic, mutualistic inquiline), and parasitic (food competitor, cleptoparasitic, predaceous symphile or synechthran). The relationships were also noted as being facultative or obligate. We suggest that the lack of evidence for a “reverse evolution” from obligatory to facultative relationships may be explained by the theory of negentropy. Within several of the lycaenid taxa there has been a change in the diet from phytophagy to aphytophagy associated with a change from cooperative to exploitative behavior towards ants. A relatively low number of species, however, seem to have followed the route from cooperative (mutualists) to exploitative behavior (cleptoparasites, predaceous symphiles, synechthrans) even though the latter may give higher returns for less investment. Even neutral behavior (no relation with ants, commensals) is more probable than exploitative behavior. We suggest that this pattern reflects both the constraints produced by the species specific nature of exploitative interactions and the stability of cooperative interactions in evolutionary terms. INTRODUCTION