共查询到20条相似文献,搜索用时 31 毫秒
1.
Variance in female quality, operational sex ratio and male mate choice in a bushcricket 总被引:8,自引:0,他引:8
Male bushcrickets, Kawanaphila nartee, exercise mate choice when nutrients are limited. Male mate choice is associated with a female-biased operational sex ratio
(OSR) that arises from an increased relative paternal investment under nutrient limitation. However, increased male choosiness
could be attributable to the fact that females vary more in fecundity, and consequently in mate quality, when nutrient limited.
Our objective was to experimentally partition the influences of OSR (male or female bias) and variance in mate quality (high
or low) and to assess their relative influence on the intensity of mate choice by male bushcrickets. Female quality was manipulated
by controlled feeding regimes that directly affected female fecundity. We found that males and females engaged in sexual interactions
sooner under a male-biased than a female-biased OSR. Males were more likely to reject females on their first encounter when
variance in female quality was high. However, the effect of quality variance on the total number of rejections during a 4-h
observation period was dependent on the perceived OSR. A male's prior experience of variance in female quality did not influence
male choosiness. Our observed rates of mate rejection conformed well with those predicted from recent theoretical models of
sexual differences in choosiness. In conclusion, our results show that the opportunity for selection via male mate choice
is influenced by an interaction between OSR and the variance in mate quality that arises within nutrient-limited populations
of females.
Received: 5 January 1998 / Accepted after revision: 25 October 1998 相似文献
2.
Time constraints and multiple choice criteria in the sampling behaviour and mate choice of the fiddler crab,Uca annulipes 总被引:9,自引:0,他引:9
Active female sampling occurs in the fiddler crab Uca annulipes. Females sample the burrows of several males before remaining to mate in the burrow of the chosen partner. Females time larval
release to coincide with the following nocturnal spring tide and must therefore leave sufficient time for embryonic development
after mating. Here we show how this temporal constraint on search time affects female choosiness. We found that, at the start
of the sampling period (when time constraints are minimal), females selectively sample the larger males in the population.
Towards the end of the sampling period (when the temporal constraints increase the costs of sampling), females are less selective.
Furthermore, we suggest that the number of males sampled (and other indices of ‘‘sampling effort’’) may not be reliable indicators
of female choosiness and may not reflect the strength of female mating preferences under certain conditions. Burrow quality
also emerged as an important criterion in final mate choice. Burrow structure potentially influences reproductive success,
and mate acceptance based on burrow structure appears to involve a relatively invariant threshold criterion. Since there is
no relationship between male size and burrow quality, females are using at least two independent criteria when choosing potential
mates. We envisage mate choice as a two-stage process. First, females select which males to sample based on male size. They
then decide whether or not to mate with a male based on burrow features. This sampling process explains how two unrelated
variables can both predict male mating success.
Received: 23 March 1995/Accepted after revision: 14 January 1996 相似文献
3.
S. Balshine-Earn 《Behavioral ecology and sociobiology》1996,39(2):107-116
Operational sex ratio (OSR) theory predicts that sexual differences in potential reproductive rates (PRRs) create biases
in the OSR and thus determine the relative strength of sexual selection (competition and choice) operating on each sex. Although
this theory is well accepted, empirical studies that quantify it are still lacking. This paper presents such a study. I measured
the natural OSR of Galilee St. Peter’s fish (Sarotherodon galilaeus) in the field (Lake Kinneret) and examined the direction of mate choice in the laboratory. The OSR in Lake Kinneret was male
biased. Both a male-biased sex ratio and higher male reproductive rates (twice as fast as females) contributed to the skew
in the OSR, but the sexual differences in PRR were shown to be the main factor causing variation in the OSR. Females, the
sex with the lower PRR, were more selective for mates. The faster male reproductive rate may explain why females are more
selective for mates despite varying less in quality.
Received: 29 May 1995/Accepted after revision: 13 April 1996 相似文献
4.
D. J. Green H. L. Osmond M. C. Double A. Cockburn 《Behavioral ecology and sociobiology》2000,48(6):438-446
Empirical and theoretical studies have only recently begun to examine how females use complex multi-component displays when
selecting mates. Superb fairy-wrens are well suited to the study of female choice because females have control over extra-group
paternity and cuckold their mates at high rates, while males possess a variety of sexually selected traits. Available evidence
suggests that females base their extra-group mate choice on the timing of male moult into breeding plumage or the onset of
display. However, males continue to perform elaborate displays throughout the season, and direct most displays to females
during their fertile period. We therefore conducted focal observations on fertile females to quantify the frequency of male
display and used microsatellite genotyping to compare the role of display rate during the breeding season and the timing of
male moult on female mate choice. We show that the addition of data on male display rate does not improve our ability to predict
which males obtain extra-group paternity. The timing of male moult into breeding plumage remains the only predictor of male
extra-group reproductive success. Nevertheless, we found that males displayed more to females that were unable to select extra-group
mates on the basis of the timing of moult or the onset of display. This raises the possibility that there are circumstances
when females use display rate to discriminate between potential extra-group sires. Overall this study supports the theoretical
prediction that females are more likely to base their mate choice on reliable indicators of male quality such as fixed morphological
traits and displays of endurance, in this case an early moult into breeding plumage and the performance of an elaborate display
during the winter, than a flexible behavioural trait such as display rate during the breeding season.
Received: 26 January 2000 / Revised: 1 August 2000 / Accepted: 26 August 2000 相似文献
5.
Mark R. Forbes Dean G. McCurdy Keiko Lui Selma I. Mautner J. Sherman Boates 《Behavioral ecology and sociobiology》2006,60(1):87-95
Potential rates of reproduction (PRR) differ between the sexes of many animal species. Adult sex ratios together with PRR
are expected to determine the operational sex ratio (OSR) defined as the ratio of fertilizable females to sexually active
males at any given time. OSR is expected to determine the degree to which one sex competes for another—the limiting sex. We
explored the potential for mate limitation in an intertidal amphipod, Corophium volutator (Pallas). Males have higher PRR than females, but males may be limiting because of extreme female-biased sex ratios observed
in this species. Consistent with this idea, late season females were less likely to be ovigerous and had smaller size-specific
clutches, both of which were associated with seasonal declines in availability of males of reproductive size. Seasonal changes
in ovigery could not be explained by seasonal changes across sites in other factors (e.g., female body size or phenology of
breeding). Smaller females were less likely to become ovigerous later in the season at three of four sites. Seasonal reductions
in clutch size also occurred among small females expected to be reproducing for their first time. In complimentary laboratory
experiments, reduced likelihood of ovigery and reduced fecundity occurred when the number of receptive females was increased
relative to availability of a reproductively active male. Our results suggest male mate limitation can occur seasonally in
this species and that male limitation is regionally widespread and may affect recruitment. 相似文献
6.
Non-aggressive mate guarding by the blue-footed booby: a balance of female and male control 总被引:3,自引:1,他引:2
Thirteen pairs of blue-footed boobies (Sula nebouxii) were observed on their colony. Pairs courted frequently and, on average, copulated 24 times during the 30 days before laying,
with 38% of those copulations occurring in the last 5 days (presumed fertile period). Males and females increased attendance
at the nest site as laying approached. Seven females performed an average seven extra-pair copulations, with 1–2 paired male
neighbors, but these were less concentrated in the presumed fertile period than within-pair copulations, and the last two
copulations of all 7 females were with their social mates. Rates of female extra-pair copulations were six times lower when
their social mate was present, and during the presumed fertile period, no female performed an extra-pair copulation in the
presence of her mate. Males did not respond to infidelity of social mates with aggression, prompt copulation, retaliatory
copulation, or increase in copulation. Seven of 13 males performed an average of five extra-pair copulations, with 1–3 paired
female neighbors, before their own mates began egg-laying. The males' extra-pair copulations represented only 4% of their
total copulations during their own mates' presumed fertile periods. Females, the larger sex, apparently control sexual access
and copulate with extra males to achieve extra-pair fertilization. Males pursue a mixed strategy: they copulate with extra
females, mostly outside their own mate's presumed fertile period, and they copulate increasingly with their social mate as
laying approaches, probably assuring some paternity by mate guarding, involving attendance and courtship. Behavior of males
and females is also consistent with other hypotheses for extensive joint nest site attendance: pairbonding, copulation access,
and territory acquisition.
Received: 14 November 1997 / Accepted after revision: 16 May 1998 相似文献
7.
Several experimental studies have shown that female birds use ornamental melanin and carotenoid plumage coloration as criteria
in mate choice. Whether females choose mates based on natural variation in structural coloration, however, has not been well
established. Male eastern bluebirds (Sialia sialis) display brilliant ultraviolet (UV)-blue plumage coloration on their head, back, wings, and tail, which is positively correlated
with condition, reproductive effort, and reproductive success. We experimentally tested the hypothesis that female eastern
bluebirds prefer as mates males that display brighter structural coloration by presenting breeding-condition females with
males of variable coloration. We conducted two types of mate-choice experiments. First, females chose between males whose
coloration was manipulated within the natural range of variation in the population; feathers were either brightened with violet
marker or dulled with black marker. Second, females chose between males with naturally dull or bright plumage coloration.
In both manipulated and unmanipulated coloration trials, female choice did not differ significantly from random with respect
to structural coloration. We found no support for the hypothesis that the UV–blue coloration of male eastern bluebirds functions
as a criterion in female mate choice. 相似文献
8.
Mate choice games, context-dependent good genes, and genetic cycles in the side-blotched lizard, Uta stansburiana 总被引:4,自引:0,他引:4
According to mate choice models, a female should prefer males with traits that are reliable indicators of genetic quality
which the sire can pass on to their progeny. However, good genes may depend on the social environment, and female choice for
good genes should be context dependent. The side-blotched lizard, Uta stansburiana, exhibits genetically based throat colors (orange, blue, or yellow) that could be used as a sexually selected signal since
they reliably predict the genetic quality of mates. The frequencies of male and female morphs cycle between years, and both
male and female morphs have an advantage when rare; thus genetic quality will depend on morph frequency. A female should choose
a sire that maximizes the reproductive success of both male and female progeny. We examine a game theoretical model that predicts
female mate choice as a function of morph frequency and population density. The model predicts the following flexible mate
choice rule: both female morphs should prefer rare males in ’boom years’ of the female cycle (e.g., ’rarest-of-N rule’), but
prefer orange males in ’crash years’ of the female cycle (’orange-male rule’). Cues from the current social environment should
be used by females to choose a mate that maximizes the future reproductive success of progeny, given the social environment
of the next generation. We predict that the cue is the density of aggressive orange females. In the side-blotched lizard,
cycling mate choice games and context-dependent mate choice are predicted to maintain genetic variation in the presence of
choice for good genes.
Received: 8 March 2000 / Revised: 26 August 2000 / Accepted: 4 September 2000 相似文献
9.
A test of male mating and hunting success in the kestrel: the advantages of smallness? 总被引:2,自引:0,他引:2
H. Hakkarainen E. Huhta Katriina Lahti Päivi Lundvall Tapio Mappes Pasi Tolonen Jürgen Wiehn 《Behavioral ecology and sociobiology》1996,39(6):375-380
We tested female choice for male wing and tarsus length and body mass in the kestrel (Falco tinnunculus), a species in which males average about 10% smaller than females. We also studied how male characters are related to their
hunting success. In the laboratory, females preferred lighter males with shorter tarsi as mates, if the difference in those
characters between competing males was larger than average. Lighter and shorter-winged males seemed to be better hunters than
heavier and longer-winged males. Field observations in a year in which voles were scarce suggested that shorter-winged males
were also better food providers in courtship feeding than longer-winged males,although in good vole years such a relationship
was not found. We argue that females may prefer to pair with smaller males, because they have higher flight performance and
better hunting success than heavier males. By doing so, females may gain direct breeding advantages. We conclude that both
female choosiness and the hunting efficiency of males well contribute to reversed sexual size dimorphism (RSD, females larger
than males) in the kestrel.
Received: 18 July 1995/Accepted after revision: 17 August 1996 相似文献
10.
Association patterns of sailfin mollies (Poecilia latipinna): alternative hypotheses 总被引:3,自引:0,他引:3
Caitlin Gabor 《Behavioral ecology and sociobiology》1999,46(5):333-340
Individuals may associate with each other due to a variety of selective forces, such as intra- and intersexual selection,
and conspecific recognition. Previous studies have concluded that mate choice governs association behavior in polygynous species
of fish. I examined whether mate choice underlies the preference for larger individuals by examining preference for association
(time spent in proximity to a fish) not only between opposite-sex individuals but also between same-sex individuals of the
live-bearing sailfin molly (Poecilia latipinna). Males and females from three size classes were tested with a large and a small object fish of the same and opposite sex.
Females preferred to associate with larger over smaller males. Males also preferred to associate with larger over smaller
females, as expected. The same female and male test fish also preferred to associate with larger over smaller fish of the
same sex. Moreover, females demonstrated no significant difference in their strength of preference (large–small) when offered
males or females. The same held true for males. When males and females were subsequently tested with one large male and one
large female, females tended to prefer large males while males showed no significant preference for association based on sex.
In another experiment, females were tested with a large female and a small male, and significantly preferred the former. These
findings suggest that association patterns may have arisen under a variety of conditions, such as predation pressures, shoaling
behavior, and associative preference behavior. The assumption that association behavior is a uniformly sufficient predictor
of mate choice in fish needs to be re-examined for P. latipinna and other species.
Received: 6 November 1998 / Received in revised form: 12 May 1999 / Accepted: 12 May 1999 相似文献
11.
Robert Brooks 《Behavioral ecology and sociobiology》1996,39(5):323-329
Models of sexual selection by female choice require heritable variation in female mating preferences in order for sexual
selection to operate. However, recent theoretical work shows that female preferences which are transmitted non-genetically
can result in exaggeration of male ornamentation. Guppies exhibit both mate copying and considerable heritable variation in
female preferences. I studied the importance of these phenomena by measuring repeatability of female mate choice, which acts
as an estimate of the upper limit to which a feature may be heritable, and the incidence of mate choice reversal in paired-trial
binary mate choice experiments. Mate choice was significantly repeatable except in the treatment where females were given
the opportunity to copy a female that contradicted their original choice. Apart from this, I found no evidence that females
copy the mate choice of others. The differences between males in ornamentation had no effect on the consistency of female
mate choice or the probability that they would reverse their original choice decision (in both controls and the copying experiment).
The interval between choice trials did not influence repeatability significantly, indicating that the independence of choice
decisions is not related to the time interval between them.
Received: 9 February 1996/Accepted after revision: 6 July 1996 相似文献
12.
When two closely related species are sympatric the process of species recognition (identifying conspecifics) and mate-quality recognition (increased fitness benefits) can yield a conflict when heterospecifics resemble high-quality conspecifics. Conflict in species versus mate-quality recognition may serve as a possible mechanism for the persistence of unisexual, gynogenetic Amazon mollies (Poecilia formosa). Amazon mollies require sperm from closely related species (e.g., sailfin mollies, P. latipinna) to start embryogenesis but inheritance is strictly maternal. When choosing mates, male sailfin mollies from populations sympatric with Amazon mollies may rely on traits indicating species identity rather than those indicating mate quality. Conversely, males from allopatric populations may rely more on traits indicating mate quality. Previous work has found that male sailfin mollies in sympatry exhibit a significantly greater mating preference for female sailfin mollies over Amazon mollies compared to males in allopatry. In addition, male sailfin mollies prefer to associate with and produce more sperm in the presence of larger conspecific females, which are more fecund. We hypothesized that male sailfin mollies experience a conflict in species recognition and mate-quality recognition in the presence of Amazon mollies that are relatively larger than female sailfin mollies. To test this hypothesis, we paired males from sympatric and allopatric populations with a larger Amazon molly and a smaller female sailfin molly. We scored the number of mating attempts that males directed to conspecific and heterospecific females. Males in most sympatric and allopatric populations demonstrate no clear preference for conspecifics. In addition, we found some evidence for a difference in mating preference between allopatric and sympatric populations with males from allopatry showing a greater heterospecific mate preference. These results indicate a conflict between species and mate-quality recognition. In sympatry this conflict may contribute to the persistence of gynogenetic Amazon mollies. 相似文献
13.
Females across many taxa commonly use multiple or complex traits to choose mates. However, the functional significance of
multiple or complex signals remains controversial and largely unknown. Different elements of multiple or complex signals may
convey independent pieces of information about different aspects of a prospective mate (the “multiple messages” hypothesis).
Alternatively, multiple or complex signals could provide redundant information about the same aspect of a prospective mate
(the “redundant” or “back-up” signal hypothesis). We investigated these alternatives using spadefoot toads, Scaphiopus couchii. Spadefoot toads primarily use calls to attract their mates, but males also exhibit sexually dimorphic coloration. We investigated
whether male coloration is indicative of male size, condition, or infection status by a socially transmitted monogenean flatworm.
We found that male coloration and dorsal patterning predicts male size and condition but not infection status. Moreover, when
we presented females with a choice between a bright male model and a dark male model, we found that females preferred the
bright model. Because aspects of males’ calls are also associated with male size and condition, we conclude that coloration
is a potentially redundant indicator of male phenotype. We suggest that coloration could enhance mate choice in conjunction
with male calling behavior by providing females with a long distance cue that could enable them to identify prospective mates
in a noisy chorus environment where the discrimination of individual calls is often difficult. Generally, such redundant signals
may facilitate mate choice by enhancing the quality and accuracy of information females receive regarding prospective mates. 相似文献
14.
Recent theory and empirical work suggests that there may be variation among females in mate preferences that is adaptive.
One of the possible mechanisms maintaining variability in preferences and preferred traits is that the benefits of mate choice
may depend on compatibility with potential mating partners. We examined fitness consequences of mate choice in a species of
fish, the sand goby, Pomatoschistus minutus with a special focus on mate compatibility. Females were given the opportunity to establish their mate preferences in a dichotomous
mate choice experiment. This information was then applied by mating the focal or control female with either the preferred
or the non-preferred male. The parental performance of the males of these four mating combinations was then measured. In a
separate experiment, we assessed the female differential allocation by determining the residual gonad weight of spawned females
as a measure of the proportion of eggs spawned. We also estimated the amount of filial cannibalism separately for both sexes.
Our results show that preferred males provided benefits in the form of an increased number of hatching eggs. This benefit
was the same when the male was mated with a focal or a control female. Hence, we found no support for benefits that depend
on mate compatibility. Neither did we find support for the hypothesis that females would lay a different number of eggs depending
on the male status. The results also indicate that male filial cannibalism has a strong role in determining hatching success
in this species. 相似文献
15.
Martin Plath Katja Kromuszczynski Ralph Tiedemann 《Behavioral ecology and sociobiology》2009,63(3):381-390
Males often face strong mating competition by neighboring males in their social environment. A recent study by Plath et al.
(Anim Behav 75:21–29, 2008a) has demonstrated that the visual presence of a male competitor (i.e., an audience male) affects
the expression of male mating preferences in a poeciliid fish (Poecilia mexicana) with a weaker expression of mating preferences when an audience male observed the focal male. This may be a tactic to reduce
sperm competition, since surrounding males likely share intrinsic preferences for female traits or copy mate choice decisions.
Here, we examined the hypothesis that a same-sex audience would affect female mate preferences less than male mating preferences. Our hypothesis was based on the assumptions that (1) competition for
mates in a fashion that would be comparable in strength to sperm competition or overt male–male aggression is absent among
Poecilia females, and (2) P. mexicana females typically form female-biased shoals, such that almost any female mate choice in nature occurs in front of a female
audience. Poecilia females (P. mexicana, surface and cave form, and the closely related gynogenetic Poecilia formosa) were given a choice between a large and a small male, and the tests were repeated while a conspecific, a heterospecific,
or no audience female (control) was presented. Females spent more time in the neutral zone and, thus, less time near the males
during the second part of a trial when an audience was presented, but—consistent with predictions—females showed only slightly
weaker expression of mate preferences during the second part of the tests. This decline was not specific to the treatment
involving an audience and was significantly weaker than the effect seen in the male sex. 相似文献
16.
In general, reproductive output in long-lived bird species increases in older compared to younger individuals. Therefore, experienced mates should be advantageous for first-time breeders. To examine requirements and consequences of experienced pair mates we investigated the first pair bonds of common terns, Sterna hirundo, recruiting to their natal colony. We found that male recruits were usually the same age as their mates, whereas female recruits were usually the younger member of the pair. In order to acquire experienced mates, it was necessary for males to arrive early in the year of recruitment. Mates with 2 or more years of breeding experience were only attainable by male recruits characterised by greater body mass and age. Female recruits arrived more than 1 week later than their experienced mates and significantly later in the season than male recruits paired with experienced females. In general, females first bred at a younger age than males, and neither the female recruits body mass nor their age was related to the level of experience of their first mate. These sex-specific differences in obtaining an experienced mate did not result in different levels of reproductive success between the sexes. Male and female recruits with mates with 2 or more years breeding experience benefited from having experienced mates: they had greater reproductive success. First-time breeders paired with mates with only 1 year of breeding experience did not differ from pairs where both members were breeding for the first time in terms of reproductive success, but clutches were larger. Our results illustrate not only different prerequisites for males and females, but also males need for experienced mates. Delayed male breeding (postponing breeding for another year), supposed to be a negative trait, and high body mass, supposed to be a trait of superior individual quality, can be combined in some individuals, improving reproductive success and showing that breeding common terns use a range of tactics to begin reproduction.Communicated by F. Trillmich 相似文献
17.
The tactics of mutual mate choice and competitive search 总被引:9,自引:0,他引:9
Rufus A. Johnstone 《Behavioral ecology and sociobiology》1997,40(1):51-59
A model of mutual mate choice is described, formulated as a dynamic game, which yields predictions about mating behaviour
under the influence of time constraints, choice costs and competition for mates. These variables were examined because they
may result in a change in the distribution of qualities among unmated individuals of both sexes over the course of the breeding
season. The model predicts that mutual choice gives rise to assortative mating, although high costs of choice and/or inaccurate
assessment both lead to lower overall correlations between the qualities (or the attractiveness) of mates. When all individuals
are present from the start of the breeding season, the correlation between the qualities of individuals pairing at a given
time declines throughout the season, so that mates are more closely matched among individuals who pair early than among those
who pair late (and extra-pair copulation may thus be more common among the latter). Delayed arrival of lower-quality individuals
may, however, lead to an increase in this correlation with time during the early part of the season. The mean quality of unmated
males and females declines over time, because more attractive individuals tend to mate sooner. As a result of this decline,
and because of time constraints, superior individuals become less choosy as the season progresses. If choice is costly, however,
then inferior individuals become more selective with time during the early part of the season, and the level of choosiness
peaks later for such individuals.
Received: 28 March 1996 / Accepted after revision: 21 September 1996 相似文献
18.
Abstract: Mate choice by females can introduce difficulties to captive breeding programs because there may be a conflict between the conservation manager's choice of mate (based on random allocation or maximizing heterogeneity) and the females' own preferences, often resulting in incompatibility and aggression. Similar effects are caused by inappropriate social contexts at the time of pairing. We manipulated the social experience of male and female harvest mice ( Micromys minutus ) to investigate whether we could enhance compatibility between randomly allocated mates by altering female preferences. In one experiment, we used a choice test to identify female preferences between two males and then varied the competitive context of unpreferred males by transferring competitor's scent marks into their cages. The manipulation caused them to increase their investment in a form of olfactory signaling (scent marking), which female rodents use as an indicator of male quality when choosing mates. The manipulation increased their attractiveness relative to the initially preferred male when the choice test was repeated. In a second experiment, we tested the effect of females' familiarity with the odor of males by transfer of male scent marks to female cages. Females preferred familiar males in choice tests and were less aggressive toward them when pairs were introduced than females paired with unfamiliar males. This kind of approach can influence mate choice, and transferring scent marks between cages or collections is an effective and practical behavioral means of improving success in conservation breeding programs. 相似文献
19.
Peter D. Dijkstra Els M. van der Zee Ton G. G. Groothuis 《Behavioral ecology and sociobiology》2008,62(5):747-755
Mate preferences on male colour have been implicated in generating and maintaining species diversity among haplochromine cichlid
fish. Their lek-like mating system suggests that not only male colour but also territory quality is instrumental in mate choice.
We assessed the relative importance of territory quality and male colour in mate choice by testing whether territory quality
can override the female preference for males of her own colour in the Lake Victoria cichlid genus Pundamilia. First, we showed in experimental groups that the dominant male preferentially monopolised a large tube relative to a small
tube. The situation mimics quality difference in rocky crevices that serves as a focal point for male courtship display. Second,
in mate-choice tests, Pundamilia nyererei females were allowed to choose between closely related P. nyererei and P. pundamilia males; these species differ strikingly in male nuptial coloration, but little else. We gave either both males the same small
tube or one of them a large tube. The preference of P. nyererei females for P. nyererei males in the control situation (where both males had a small tube) was significantly diminished in favour of P. pundamilia males when the latter had the large tube. The results provide experimental evidence that differences in territory quality
can override the female preference for males of her own colour. This finding is critical for a recent hypothesis proposing
that male competition for mating territories can facilitate the process of sympatric speciation by sexual selection. 相似文献
20.
Variation in reproductive potential usually occurs among individuals of both sexes; for example, some individuals may carry
more gametes or be able to continue to generate more gametes in their reproductive life than others. Therefore, to maximize
their reproductive success, both sexes are expected to show adaptations for mate choice. However, most authors concentrated
on how females choose their mates with the belief that females invest more in reproduction than males, and males are generally
eager to pair with any female. In this paper, we report our work on a polygamous moth, Ephestia kuehniella Zeller (Lepidoptera: Pyralidae), with special emphasis on male pre- and in-copulation mate choice in relation to the reproductive
quality and re-copulation potential of females. We show that in E. kuehniella, younger and heavier females have significantly higher reproductive value than older and lighter ones, and male sperm supply
significantly decreases over successive copulations. Males exercise pre-copulation mate choice by selecting females with higher
reproductive potential for copulation and in-copulation mate choice by allocating more sperm to females with higher reproductive
potential. However, high-quality females are more likely to re-copulate than low-quality ones, and allocation of more sperm
to females by males does not increase female reproductive outputs. It is suggested that the allocation of more sperm to high-quality
females functions to increase sperm competitiveness against rivals. 相似文献