CHAPTER SUMMARY

Among vertebrates, fish show by far the greatest variability of alternative reproductive tactics (ARTs). Usually, males attempting to monopolize access to females or fertilizations are parasitized by conspecific male competitors (Taborsky 1997). This is so common in fish (Mank and Avise 2006) that it appears to be the rule rather than the exception: in fish with external fertilization, 170 species belonging to 32 families have been described to show ARTs (Table 10.1). Apart from being common, ARTs in fish are also exceptionally variable. Parasitic males exploiting the effort of conspecific competitors may do so by surreptitious participation in spawning; they may mimic females in appearance and behavior to reach their goal; intercept approaching mates or steal eggs from neighbors to attract mates to their nest; force copulations in viviparous species; gain access to mates by cooperating with their competitors; or oust a territory owner aggressively to spawn in his nest before letting him care for their brood. Sometimes, three or more alternative tactics may exist within a species (Taborsky 1994, 2001, Avise et al. 2002). Our understanding of sexual selection mechanisms and the concepts underlying conventional classifications of mating patterns largely ignore the existence and importance of ARTs (Emlen and Oring 1977, Wittenberger 1979, Davies 1991, Andersson 1994, 2005). One could argue that the way reproductive behaviour in animals is viewed and categorized today would be different if it had been developed on the basis of fish reproduction instead of bird mating systems.