RESEARCH PAPER Multiple Sexual Ornamentation Signals Male Quality and Predicts Female Preference in Minnows Jukka Keka ¨ la ¨ inen*, , Hannele Valkama , Hannu Huuskonen & Jouni Taskinen* * Department of Biological and Environmental Science, University of Jyva ¨ skyla ¨ , Jyva ¨ skyla ¨ , Finland  Ecological Research Institute, University of Eastern Finland, Joensuu, Finland Introduction In many species, sexual displays are often highly complex, involving many different signal compo- nents (Candolin 2003). Different ornaments may indicate quality in different time scales or different traits may reflect different aspects of signaller quality (Møller & Pomiankowski 1993; Fitzpatrick 1998; Brooks & Couldridge 1999; Badyaev & Hill 2000; Candolin 2003). Red, orange and yellow ornaments of birds and fish usually consist of carotenoids (Aquilera & Amat 2007). Because animals are unable to synthesize these pigments, they must acquire carotenoids from food (Fox 1976). Caroten- oid ornaments have been demonstrated to indicate fertilization success and parental ability as well as certain genetic benefits in various animal taxa (Lozano 1994; von Schantz et al. 1999; Preault et al. 2005; Locatello et al. 2006; see also Folstad & Karter 1992). Instead, dark melanin pigments are synthesised from amino acids, as a by-product of metabolism Correspondence Jukka Keka ¨ la ¨ inen, Ecological Research Institute, University of Eastern Finland, PO Box 111, FI-80101 Joensuu, Finland. E-mail: jukka.s.kekalainen@uef.fi Received: March 3, 2010 Initial acceptance: April 7, 2010 Final acceptance: May 14, 2010 (J. Wright) doi: 10.1111/j.1439-0310.2010.01802.x Abstract Sexual ornamentation often consists of multiple components. Different sexual signals may indicate different aspects of mate quality or reflect quality in different time scales. On the other hand, same signals can have a dual function and are used both in male–male competition and courtship. Many fish species are capable of rapidly altering their colour- ation (ephemeral colour changes), but this capability is usually ignored in sexual selection studies. Here, we used experimentally manipulated social environments to study the ephemeral colour changes in multi- component sexual signals of male minnows (Phoxinus phoxinus) during male–male competition and female choice. We found that the dominant males courted the females more actively and had redder and ⁄ or darker skin colouration than the subordinate males. Furthermore, darkness dif- ference between subordinate and dominant males increased in the pres- ence of female, which suggests that the male–male competition may increase the honesty of signalling and thus facilitate female choice. In support of this hypothesis, females had a strong behavioural preference towards the more colourful males, which may indicate female choice. As colourful males often had a higher social status than paler individu- als, it is possible that females base their preference on male status, not only the colouration per se. In any case, our results suggest that sexual ornamentation of male minnows may signal status, courting activity and superior quality of the males and that these signals may have a dual function in both male–male competition and female choice. Females preferred different ornamental traits (dark and red colour patterns) rela- tively equally, indicating that mate choice is based on multiple cues. Ethology Ethology 116 (2010) 895–903 ª 2010 Blackwell Verlag GmbH 895 ethology international journal of behavioural biology