The measurement of sexual selection on females and males

As in any field of research, the study of sexual selection is subject to ongoing debate over definitions and interpreta- tions of the fundamental concepts involved. These arguments generally promote progress, as they highlight areas where current explanations are incomplete. Here we briefly review two ongoing discussions in the sexual selection literature. First, the defini- tion of sexual selection has received renewed interest in light of increasing research effort into when and how it operates in fe- males. Second, how best to measure sexual selection is an ongoing subject of debate; in practice, recognition that the appropriate measures depend on the focus of the specific study, and that multiple measures should be employed wherever possible, seems to provide the most informative approach. The wide scope of recent empirical work in these and related areas, with the application of new techniques and approaches, reflects that the field of sexual selection is being constantly expanded and enriched (Current Zoology 59 (4): 558-563, 2013).