Mating behaviour in a feral guppy, Poecilia reticulata, population fro
m Durban, South Africa was examined. Males bear carotenoid (orange) an
d melanin (black) spots and low levels of iridescent and yellow pigmen
t. Areas of colour, body size and lengths of the dorsal fin and introm
ittent organ (gonopodium) were studied as female mate-choice cues. Att
ractiveness was positively related to the degree of orange coloration
in all tests, and with the length of the gonopodium in some tests. Asy
mmetry of colour spots was investigated and it was concluded that eith
er orange and black spots are not condition-dependent ornaments or the
expected negative relationship between expression of condition-depend
ent ornaments and fluctuating asymmetry does not occur in these guppie
s. Several hypotheses regarding the maintenance of multiple secondary
sexual characters are discussed. (C) 1995 The Association for the Stud
y of Animal Behaviour