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Relevant publications
Lüpold, S., M.K. Manier, N. Puniamoorthy, C. Schoff, W.T. Starmer, S.H. Lüpold, J.M. Belote and S. Pitnick. 2016. How sexual selection can drive the evolution of costly sperm ornamentation. Nature  533: 535–538.

Puniamoorthy, N., W.U. Blanckenhorn and M.A. Schäfer. 2012. Differential investment in pre- versus post-copulatory sexual selection reinforces a cross-continental reversal of sexual size dimorphism in Sepsis punctum (Diptera: Sepsidae). Journal of Evolutionary Biology 25: 2253–2263.

Polyandry is widespread in most animal lineages and it refers to mating systems where individual females mate with multiple males. For years, most biologists focused on precopulatory sexual selection i.e. competition among individuals for access to the opposite sex (e.g. male-male competition for territorial defense; male courtship for female choice) and mating success as a primary indicator of fitness. However, polyandry can extend the competition for reproductive fitness far beyond actual copulation. For instance, in insects most females have long term sperm storage organs and when they mate with multiply, it can generate competition among sperm of different males for the fertilization of the eggs.  This postcopulatory process is known as sperm competition (Parker 1970).

We are interested in how polyandry and sperm compeitition might vary among closely related species and widespread populations as well as the consequences that can have for reproductive trait divergence and reproductive isolation.