Polymorphism and Mating Tactics

Video of David Lank’s captive ruffs taken by Sue McRae

Male lek-breeding ruffs (Philomachus pugnax) manifest a stable genetically based polymorphism in mating tactics such that three alternative male morphs may exist simultaneously within a given population. The majority of males are dark-plumaged “territorial” individuals that defend females against other territorial males. Lighter-plumaged “satellite” males are recruited onto a territory holder’s court, where they obtain copulations by allying themselves with territorial males. Finally, relatively rare, cryptic males referred to as “faeders,” fail to develop normal male breeding plumage and do not perform male displays, but mimic females and thereby sneak copulations without being detected by resident and satellite males. Here, a territorial male (brown mottled plumage) and accompanying satellite male (with pronounced white head ornamentation) display for females, while a faeder (distinguished here by blue leg bands) waits nearby. In the final segment of the clip, the faeder (poised initially on a rock) attempts copulation by interposing himself between the copulating territorial male and a receptive female.

FURTHER READING: Lee A. Dugatkin, Principles of Animal Behavior, 3rd ed. (New York: W. W. Norton, 2013), chap. 4, “Molecular Genetics and Development”; chap. 7, “Sexual Selection”; chap. 8, “Mating Systems.” J. Jukema and T. Piersma, “Permanent female mimics in a lekking shorebird,” Biology Letters 2 (2006), pp. 161-164.