EBERHARD, WG; STRI and Univ. de Costa Rica: Selective Cooperation vs. Antagonistic Coevolution: Competing Offspring of Bateman’s Principle

Several major empirical patterns in nature conform to the Bateman principle that male reproduction is generally more limited by access to mates than is that of females: males not females generally initiate sexual interactions; males generally court females rather than vice versa; fights over access to mates are generally between males, not between females; and males are generally less discriminating with respect to sexual partners than females. But another aspect of sexual interactions that has often been linked to the Bateman asymmetry, is being abandoned: the “myth of the passive female”. Females play important roles in determining which males in a population reproduce. Abandonment of the passive female myth has taken three general forms in recent discussions. Wiley and Posten noted that the female can have important but otherwise subtle effects on paternity, even when she is apparently completely passive (indirect female choice). Several authors propose that the female has an active role in “arms races” with males over control of events associated with copulation and fertilization (male-female conflict, or antagonistic coevolution). Others use traditional female choice to interpret many of the same types of interaction. The male-female conflict ideas come close to perpetuating the old “female passive” ideas, in that the female is not seen as actively choosing among males, but rather being overcome by the male despite her non-selective resistance. In this talk I will summarize data relating and contrasting antagonistic coevolution and traditional female choice, and show that in the evolution of many morphological characteristics, traditional female choice has apparently been a more important force than antagonistic coevolution.