02869nas a2200229 4500008004100000245010900041210006900150260000900219300001400228490000700242520215000249653002702399653001602426653002702442653001402469653002102483100001902504700001602523700001502539700002502554856006002579 2004 eng d00aJuvenile infection and male display: testing the bright male hypothesis across individual life histories0 aJuvenile infection and male display testing the bright male hypo c2004 a722 - 7280 v153 a

Current tests of the bright male hypothesis focus on assays of adult disease resistance and their relation to male trait development and female choice. We suggest that if parasites have significant harmful effects on juvenile stages of a host, then females selecting males that effectively signal juvenile parasite resistance may gain a significant “good genes” benefit. Currently, there is no information on juvenile and adult infection or resistance in the same male and whether adult male displays signal juvenile parasite resistance. In the present study, we measure infection of the ectoparasitic louse, Myrsidea ptilonorhynchi, in individual male satin bowerbirds (Ptilonorhynchus violaceus) both as juveniles and nine or more years later as adults. We test hypotheses that examine the role of juvenile parasite infection in mediating sexual selection. We found that (1) juvenile infection is higher than adult infection in the same individuals, (2) adult males able to hold display sites have lower juvenile infection, and (3) juvenile and adult infection in the same individuals are not significantly correlated. In addition, comparisons among a larger set of individuals from a single year show that blood and ectoparasite infections are highly correlated, and both decrease with male age and are inversely related to male courtship success. These results, combined with the evidence that females mate exclusively with bower-holding males support the hypothesis that females use adult male display traits to identify males with a high level of juvenile disease resistance. We suggest that effective tests of the bright male hypothesis should include (1) assessment of infection resistance in both subadult and adult life history stages, (2) tests of whether differences in age-specific resistance are indicated in adult male displays, and (3) tests to determine if females attend to these traits in mate choice. Although these requirements increase the difficulty of testing the bright male hypothesis, they are necessary for a more accurate assessment of the effects of parasites on male display and female choice.

10abright male hypothesis10amate choice10aMyrsidea ptilonorhynch10aparasites10asexual selection1 aBorgia, Gerald1 aEgeth, Marc1 aUy, Albert1 aPatricelli, Gail, L. uhttps://academic.oup.com/beheco/article/15/5/722/31840802383nas a2200193 4500008004100000245009900041210006900140260000900209300001400218490000700232520179100239653001802030653001602048653001302064653002002077100001902097700001602116856005702132 1989 eng d00aFemale choice for parasite-free male satin bowerbirds and the evolution of bright male plumage0 aFemale choice for parasitefree male satin bowerbirds and the evo c1989 a445 - 4540 v253 a

Hamilton and Zuk proposed that bright male plumage may have evolved in males of polygynous species as a result of female preferences for males that are able to demonstrate their resistance to disease. They predicted an inverse correlation between female mating preferences and the level of parasitic infection of males. We found such a correlation between the level of infection by acommon ectoparasite (Myrsidea ptilonorhynchi: Menoponidae) and mating success of male satin bowerbirds (Ptilonorhynchus violaceus). In addition, we tested and were able to confirm three other predictions derived from their model: that (1) older males had fewer parasites than their younger counterparts, (2) levels of individual parasitic infection are highly correlated between years, and (3) that individuals resighted in successive years are less parasitized than those that fail to return. These results support the bright male model, but they are also consistent with two other hypotheses that may explain plumage dimorphism based on the level of parasitic infection. The correlated infection model suggests that females choose males with few ectoparasites because of a correlation between the level of ectoparasitic infection and heritable resistance to internal infections. In the parasite avoidance model, females favor parasite free males because it lowers their own prospects for parasitic infection. Our data did not show the predicted relationship between parasite numbers with plumage quality that is needed to support the bright male hypothesis, nor did it show the inverse correlation between male condition and parasite numbers that is predicted by both the bright male and correlated infection hypotheses. Our results are most consistent with the parasite avoidance hypothesis.

10ahost behavior10aMenoponidae10aMyrsidea10aPtilonorhynchus1 aBorgia, Gerald1 aCollis, Ken uhttps://link.springer.com/article/10.1007/BF0030019101643nas a2200193 4500008004100000245006800041210006700109260000900176300001400185490000700199520106600206653001801272653002401290653001601314653001901330653002401349100001901373856005701392 1986 eng d00aSatin bowerbird parasites: A test of the bright male hypothesis0 aSatin bowerbird parasites A test of the bright male hypothesis c1986 a355 - 3580 v193 a

The number of a common parasite (Cuclotogaster sp.) on male satin bowerbirds was related to male mating success in a test of Hamilton and Zuk's (1982) bright male hypothesis. The data do not show the expected inverse correlation between female mating preferences and the level of parasitic infection of males predicted by that model. Nearly all matings are accomplished by bower-holding males (Borgia 1985a), but the vast majority of these males were uninfected. There were large differences in mating success among the uninfected bower holders, but this could not be explained by between male differences in the level of parasitic infection. From this I conclude that levels of parasitic infection are not now an important direct cause of intermale variation in mating success. The results are, however, consistent with a hypothesis that a low level of infection is indicative of the overall healthy condition of a male. If this is true, it supports the hypothesis that the ability to hold a bower may be an indicator of male condition to females.

10aFemale Mating10aInverse Correlation10aMale Mating10aMating Success10aParasitic Infection1 aBorgia, Gerald uhttps://link.springer.com/article/10.1007/BF0029570801512nas a2200145 4500008004100000245008900041210006900130260000900199300001400208490000700222520104600229100001901275700001501294856005701309 1990 eng d00aParasites and bright male plumage in the satin bowerbird (Ptilonorhynchus violaceus)0 aParasites and bright male plumage in the satin bowerbird Ptilono c1990 a279 - 2850 v303 a

Results from our field studies of the satin bowerbird (Ptilonorhynchus violaceus) suggest that females choose males as mates based on their level of infection with the ectoparasite (Myrsidea ptilonorhynchi: Menoponidae). We evaluated predictions from three hypotheses for why this pattern of choice might evolve. The bright male and correlated infection models both suggest that females choose parasite free males because these males are more likely to sire parasite resistant offspring. The bright male hypothesis suggests that females are able to gauge infection based on plumage brightness. The correlated infection hypothesis claims that females assess resistance to endoparasites through a correlated effect on ectoparasites. In the parasite avoidance model female choice is shaped by the proximate benefits of avoiding infection. Six predictions from these models were tested using information on patterns of infection in satin bowerbirds. Of these models the parasite avoidance model was best supported by the available data.

1 aBorgia, Gerald1 aCollis, K. uhttps://academic.oup.com/icb/article/30/2/279/164308