A field test of the Hamilton–Zuk hypothesis in the Trinidadian guppy (<Emphasis Type="Italic">Poecilia reticulata</Emphasis>) |
| |
Authors: | Christopher H Martin Sönke Johnsen |
| |
Institution: | (1) Biology Department, Duke University, Box 90338, Durham, NC, USA |
| |
Abstract: | The Hamilton–Zuk hypothesis proposes that females prefer male secondary sexual traits because they are honest indicators of
parasite resistance. Despite the attention that this hypothesis has received, its role in sexual selection remains equivocal.
This study presents the first field test in guppies of two key predictions of the Hamilton–Zuk hypothesis: (1) that within
populations, the most highly ornamented males have the fewest parasites and (2) that among populations, males in high parasite
populations have the most conspicuous ornaments. Five hundred male guppies from 19 distinct populations in the Northern Range
of Trinidad were inspected for Gyrodactylus parasites and photographed. Eight measures of orange spot ornamentation were used to test the predictions: hue, saturation,
lightness, relative area, number, and area-weighted hue, saturation, and lightness. Parasite load had no significant effect
on any of these measures. There was also no relationship between orange spot ornamentation and parasite abundance among populations.
Guppies from high-predation environments had significantly more parasites, and their orange coloration was lighter and less
saturated than that in guppies from low-predation environments. Despite previous lab results, this study found no relationship
between parasite load and male orange spot ornamentation. |
| |
Keywords: | Female choice “ Good genes” models Guppy Gyrodactylus Hamilton– Zuk hypothesis Poecilia reticulata Sexual selection |
本文献已被 SpringerLink 等数据库收录! |
|