golden hamsters (Mesocricetus auratus,Huck et al. 1986).
In contrast, montane voles (Microtus montanus) and
meadow voles (Microtus pennsylvanicus), both of which
mate with multiple males, showed no preference between
the two types of males in similar test situations (Pierce and
Dewsbury 1991; Salo and Dewsbury 1995). There are no
data on the consequences of these preferences. To test Pierce
and Dewsbury’s hypothesis, more studies are needed from
socially monogamous species to see if they differ from pro-
miscuous species.
It has been suggested that female selectivity for a mate is
related to the mating system, with females of monogamous
species being more choosy than females of polygamous spe-
cies (Salo and Dewsbury 1995). Aside from fertilization as-
surance, females of monogamous species may also be ex-
pected to prefer unmated males, to ensure that she and her
offspring are the primary beneficiaries of the male’s pater-
nal effort.
Material benefits
Material benefits in the form of paternal care are rare in
rodents, because most rodents are polygynous or promis-
cuous. In these species, males provide no paternal care, be-
cause they benefit more from mating with multiple females
than by living with just one and helping to rear offspring.
In socially monogamous species, the willingness and ability
to provide paternal care (e.g., huddling over pups, licking
pups, retrieving pups back to the nest — Gubernick and Al-
berts 1987; Solomon 1993b; Lonstein and DeVries 1999;
McGuire and Bemis chap. 20, this volume) may be impor-
tant for female reproductive success. For example, female
Djungarian hamsters (Phodopus campbelli) and Califor-
nia mice (Peromyscus californicus) need help from their
male partner to successfully rear offspring (Wynne-Edwards
1987; Gubernick and Teferi 2000). However, the relation-
ship between female mate choice and male parental care is
unknown.
Ownership of a territory may be another important ben-
efit for females, since lactating females need a safe, se-
cure nest site with high-quality food resources nearby. In
house mice (Mus musculus), females mate more frequently
with males that defend high-quality territories (Wolff, R. J.,
1985), but whether they choose the male, the territory, or
the combination is not known.
Good genes
If sexually selected traits are strongly correlated with a
male’s physical condition, males in good condition should
exhibit traits that are considered attractive to females (An-
dersson 1994). Females may discriminate among males
based on these characteristics, choosing males with heri-
table characteristics that would confer increased viability
(Drickamer et al. 2000) or attractiveness (Weatherhead and
Robertson 1979) to their offspring. For example, if charac-
teristics that affect dominance are heritable, females may be
predisposed to mate with dominant males so their offspring
may inherit traits associated with dominance (Drickamer
1992a; Horne and Ylönen 1998). We will discuss three
ways in which the quality of the genes a male possesses may
be important for female mate choice.Resistance to infection
Clayton (1991) and Zuk (1992) suggest that female choice
should be influenced by the ability of males to resist a par-
asitic infection. Females may also benefit indirectly if resis-
tance has a genetic basis. In the latter instance, resistance
may be passed on to offspring (Potts and Wakeland 1993).
Females and their offspring may benefit directly by avoiding
infection, either with a parasite or disease, if females are
able to discriminate between uninfected and infected males
and mate less frequently with the latter (Kavaliers and Col-
well 1995a, 1995b), although this benefit does not have a
genetic basis.
Kavaliers and Colwell (1995a) reported that female
house mice are able to discriminate between the odors of
parasitized and nonparasitized males, and females avoid the
odors of parasitized males (Kavaliers and Colwell 1995a).
Furthermore, Penn et al. (1998) reported that female house
mice are able to assess a male’s infection status via odor
cues present in male urine, and that infection eliminates the
attractiveness of the male’s odor cues. Only one study, Klein
et al. (1999), goes beyond testing odor preference. In this
study, investigators found that female prairie voles pre-
ferred the odors of uninfected to infected males, but there
was no difference in time spent with either type of male. Al-
though these laboratory studies suggest that male infection
status may influence female attraction to males, it is not
known whether this is true in nature.Dominance status
The offspring of dominant males could have greater fitness
either because dominance is genetically linked to other
traits that improve survivorship or because traits that affect
dominance status are heritable (Drickamer 1992a; Horne
and Ylönen 1998). If that is the case, then sons of dominant
males should have superior mating success due to female
choice or male-male competition (Weatherhead and Rob-
ertson 1979). Females would then benefit indirectly by the
increased reproductive success of their offspring (Dewsbury
1982b; Ellis 1995).
Females may also gain direct benefits from mating with
dominant males because dominant males are better able to46 Chapter Four