The reproductive strategy of butterfly males can be defined as being to maximize the number of females mated. We have earlier shown that, if the eclosion period of females is regarded as given, males should emerge before females to achieve maximal reproductive success. However, females may also be considered to have a reproductive strategy with respect to the issue "when to emerge". In this paper we assume that females are selected to minimize the time spent unmated (to minimize prereproductive death), and analyze when females should optimally emerge in relation to males to achieve this end. We show that there is no conflict between the sexes with respect to the timing of eclosion when the length of the eclosion period is approximately equal for males and females. Thus, protandry should be considered a reproductive strategy of both males and females.

No abstract

In butterflies and many other insects there is a general tendency for males to emerge before females. This is known as protandry. In this paper we advance the hypothesis that protandry is a reproductive strategy of males, resulting from competition for mates, and should primarily occur in species maintaining female monogamy. Our hypothesis is corroborated by applying a mathematical treatment to a theoretical population with seven defined properties, all of which are argued to be reasonable assumptions for natural populations.

No abstract

No abstract