Diurnal and seasonal changes in the mate‐locating behavior of the satyrine butterflyLethe diana

Abstract

The time schedule of mate‐locating behavior in the male satyrine butterflyLethe dianawas studied. Males displayed territorial behavior only in the afternoon, but it was not known whether they attempted to locate mates in the morning. In order for males of most butterfly species to mate with a virgin female, it would be most effective to initiate mate‐locating behavior in the morning, when synchronous eclosions occur. Males ofL. dianaflew patrols in the morning and displayed territorial behavior in the afternoon. The cost of territorial behavior is probably less than that of patrolling, as territorial flights are shorter than those when patrolling. The temporal switching of mate‐locating behavior is theoretically favored, since the reproductive value of females decreases later in the day, when males perform the less costly mate‐locating behavior. Thus, the diurnal switching of male mate‐locating behavior may be an adaptive strategy in response to the rapid decline in the reproductive value of females over the course of a day.