Parasites and mate choice in red jungle fowl

Marlene Zuk, Randy Thornhill, J. David Ligon, Kristine Johnson

Research output: Contribution to journalArticle

145 Citations (Scopus)

Abstract

Captive flocks of red jungle fowl (Gallus gallus) experimentally infected with the intestinal nematode Ascaridia galli were used to test Hamilton and Zuk's (1982) hypothesis that parasites adversely affect male secondary sex characters and that females prefer unparasitized over parasitized males. Infected chicks grew more slowly than uninfected controls, with the effect particularly pronounced on comb length rather than tarsus length or body weight. At sexual maturity, infected roosters had duller combs and eyes, shorter combs and tail feathers, and paler hackle feathers than control roosters. In experimental mate choice tests, females preferred unparasitized over parasitized roosters by about 2: 1, and an analysis of covariance revealed that the hens were using the traits on which the two groups differed to make their mate choice decisions. Finally, in a test of an extension of the Hamilton and Zuk hypothesis, control and infected males were not distinguishable based on non sexually-selected characters such as bill size, suggesting that parasites have a disproportionately larger effect on ornamental traits.

Original languageEnglish (US)
Pages (from-to)235-244
Number of pages10
JournalIntegrative and Comparative Biology
Volume30
Issue number2
DOIs
StatePublished - 1990

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comb (integument)
parasites
Comb and Wattles
Gallus gallus
roosters
mating behavior
tropical regions
Feathers
Parasites
feathers
Ascaridia
Ascaridia galli
Analysis of Covariance
body weight
Flock
testing
maturity
sexual maturity
Ankle
bill

Cite this

Parasites and mate choice in red jungle fowl. / Zuk, Marlene; Thornhill, Randy; Ligon, J. David; Johnson, Kristine.

In: Integrative and Comparative Biology, Vol. 30, No. 2, 1990, p. 235-244.

Research output: Contribution to journalArticle

Zuk, Marlene ; Thornhill, Randy ; Ligon, J. David ; Johnson, Kristine. / Parasites and mate choice in red jungle fowl. In: Integrative and Comparative Biology. 1990 ; Vol. 30, No. 2. pp. 235-244.
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