Subterranean Fishes of the World

3323

2008

Behavior

73-98

145

Male mating behavior and costs of sexual harassmentfor females in cavernicolous and extremophilepopulations of Atlantic mollies (Poecilia mexicana)Martin Plath1,2,3,4)(1Unit of Animal Ecology, Department of Biochemistry and Biology, University ofPotsdam, Maulbeerallee 1, 14469 Potsdam, Germany;2Unit of Evolutionary Biology andSystematic Zoology, Department of Biochemistry and Biology, University of Potsdam,Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany;3Department of Zoology, Universityof Oklahoma, 730 Van Vleet Oval, Norman, OK 73019, USA)(Accepted: 7 October 2007)SummaryThe Atlantic mollyPoecilia mexicanainhabits a variety of different habitat types, some ofwhich are characterized by physicochemical stressors, such as toxic hydrogen sulfide (H2S),or the fish occur in lightless subterranean (cave) habitats. Using five different populationsfrom surface habitats with or without H2S, and from a sulfidic and a non-sulfidic cave, I askedhow extreme environmental conditions affect behavioral evolution in this species. I examinedmale sexual behavior, and potential costs of male sexual harassment to females, determinedas the reduction of female feeding times in the presence of a harassing male. In all popula-tions with at least one physicochemical stressor present (H2S or absence of light), a reductionin male sexual activity was recorded. While females from habitats without physicochemi-cal stressors spent less time feeding around males, no such costs of male harassment weredetected in populations from extreme habitats. It is discussed that energy limitation may bethe driving force selecting for reduced male sexual activity, since fish from all habitats withpresence of physicochemical stressors show a low body condition factor under natural condi-tions.Keywords: cavefish, coercive mating, hydrogen sulfide, mating tactics, sexual conflict.

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