1 Visual-based male mate preference for conspecific females in mutually ornamented fish: possible 2 importance of species recognition hypothesis 3 4 Keisuke Atsumi1, Osamu Kishida2 and Itsuro Koizumi1,3 5 6 1Graduate School of Environmental Science, Hokkaido University, N10W5 Sapporo, Hokkaido 7 060-0810, Japan 8 2Tomakomai Experimental Forest, Field Science Center for Northern Biosphere, Hokkaido University, 9 Takaoka, Tomakomai, Hokkaido 053-0035, Japan 10 3Faculty of Environmental Earth Science, Hokkaido University, N10W5 Sapporo, Hokkaido 060-0810, 11 Japan 12 13 Corresponding author: K. Atsumi 14 Tel.: +81 11 706 2620; fax: +81 11 706 4864; email:
[email protected] 15 ORCID ID: https://orcid.org/0000-0002-8206-4977 16 17 E-mail address: 18 Keisuke Atsumi:
[email protected] 19 Osamu Kishida:
[email protected] 20 Itsuro Koizumi:
[email protected] 21 22 Running head: Female nuptial coloration can reduce hybridization 23 24 Type of paper: original paper 25 Number of figures: 3 (1 in supplement) 26 Number of tables: 1 (2 in supplement) 27 1 28 Abstract 29 Because sexual selection typically acts on males, evolution of conspicuous ornamentation in females has 30 been understudied. Genetic correlation between sexes and sexual or social selection on females have 31 been proposed to explain female ornamentation, but they cannot fully explain observed patterns in 32 nature such as female ornamentation in non-territorial, promiscuous species. The species recognition 33 hypothesis, which postulates that ornamentation is adaptive because it prevents maladaptive 34 hybridization, might plausibly explain female ornamentation. We examined the possibility of this 35 hypothesis in two sympatric, non-territorial, promiscuous fish species.