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1.
We studied mate attraction by females of the praying mantid, Tenodera aridifolia sinensis, testing honest signaling of mate availability versus deceptive signaling to attract males for sexual cannibalism. We experimentally
varied female diet and mating history and measured the rate of attraction of a wild population of males to caged females.
Honest signaling theory predicts that virgin females will attract males at the greatest rate whereas deceptive signaling predicts
that hungry females (which are more likely to cannibalize males) will attract more males, particularly among non-virgin females.
Our results show that hungry females did not attract more males than well-fed females. Indeed, the opposite was true: hungry
females attracted significantly fewer males. Moreover, hungry females were no more likely than well-fed females to attract
males subsequent to mating, and mated females attracted males at a lower rate than did virgin females. We also observed female
T. aridifolia sinensis and male Mantis religiosa arriving at the caged females and we discuss the significance of these observations. The results refute the hypothesis of
deceptive signaling and show that mate attraction signals of female T. aridifolia sinensis are honest indicators of female mate availability and a lower risk of sexual cannibalism. 相似文献
2.
D. S. Pope 《Behavioral ecology and sociobiology》2000,47(6):432-437
Many territorial advertisement signals are thought to be dual-function signals, directed to both rival male and receptive
female conspecifics. However, few studies have tested this assumption by examining whether in fact both sexes are likely to
elicit signaling behavior from territorial males. In this study, I experimentally manipulated the social context of male sand
fiddler crabs (Uca pugilator) to investigate the effect of different audiences on the performance of the claw-waving display, a territorial signal that
is often presumed to be directed to both males and females. To test whether males perform this signal to both audiences, I
measured the frequency of waving behavior by focal males when housed in field enclosures alone, with only males, with only
females, or with both males and females. Focal males waved at a low frequency when alone, and the presence of males had no
effect on their level of waving. However, in the presence of females, focal males showed a significantly higher level of waving,
whether or not males were also present. In addition, there was no association between fighting and waving behavior. This experiment
provides evidence that from the perspective of the signaling male, the claw-waving display of U. pugilator is not a dual-function signal but rather is primarily directed to receptive females.
Received: 16 December 1999 / Received in revised form: 1 February 2000 / Accepted: 19 February 2000 相似文献
3.
Although many avian eggs appear to be cryptically colored, many species also lay vibrant blue green eggs. This seemingly conspicuous
coloration has puzzled biologists since Wallace, as natural selection should favor reduced egg visibility to minimize predation
pressure. The sexual signaling hypothesis posits that blue green egg coloration serves as a signal of female quality and that
males exert post-mating sexual selection on this trait by investing more in the nests of females laying more intensely blue
green eggs. This hypothesis has received mixed support to date, and most previous studies have been conducted in cavity-nesting
species where male evaluation of his partner’s egg coloration, relative to that of other females, may be somewhat limited.
In this study, we test the sexual signaling hypothesis in colonially nesting ring-billed gulls (Larus delawarensis) where males have ample opportunity to assess their mate’s egg coloration relative to that of other females. We used correlational
data and an experimental manipulation to test four assumptions and predictions of the sexual signaling hypothesis: (1) blue
green pigmentation should be limiting to females; (2) extent of blue green egg coloration should relate to female quality;
(3) extent of blue green egg coloration should relate to offspring quality; and (4) males should provide more care to clutches
with higher blue green chroma. Our data provide little support for these predictions of the sexual signaling hypothesis in
ring-billed gulls. In light of this and other empirical data, we encourage future studies to consider additional hypotheses
for the evolution of blue green egg coloration. 相似文献
4.
In many species of East African cichlids, males build sand craters or “bowers” to attract females for spawning. It is commonly
assumed that these exaggerated sexual traits have a function similar to bodily ornaments. In non-bodily ornaments, however,
the behaviour creating the structure may serve as an additional source of information to potential partners, providing multiple
signals for mate choice. We tested whether and to what extent females use these signals for choosing males by observing the
individual sampling behaviour of female Cyathopharynx furcifer in the field. In addition, we experimentally manipulated crater characteristics in the field and laboratory. We found that
females spawn preferably with owners of large and well-maintained craters, but when crater size was enlarged or reduced, the
resulting building activity of crater owners affected female choice more strongly than the manipulated crater size per se. We discuss the importance of multiple signals in species constructing extended phenotypes. 相似文献
5.
A wide variety of hypotheses has been proposed to explain the structural diversity in bird song repertoires. Song diversity
is frequently described in terms of song “types” or within-type “variants.” Male Puget Sound white-crowned sparrows, Zonotrichia leucophrys pugetensis, produce variants of their single adult song type by altering the number of repetitions of syllables in the terminal trill.
We tested whether variation in trill length correlated with distance to the receiver and with signaling context as predicted
by the eavesdropping avoidance hypothesis and the strategic signaling hypothesis. In accordance with the eavesdropping avoidance
hypothesis, males sang variants with shorter trills, and sang quieter and less frequently when near their mate during the
incubation phase than during spontaneous singing while unpaired. Males also sang variants with short trills, but at a high
rate and variable amplitude when within 10 m of an opponent during close male–male territorial interactions. In agreement
with the strategic signaling hypothesis, males decreased trill length immediately before chasing an opponent, but did not
change length consistently prior to flight. We conclude that the occurrence of short quiet songs sung near the mate agrees
with predictions of the eavesdropping avoidance hypothesis, while short songs sung near other males are best explained by
the strategic signaling hypothesis. Trill length variation may be a conventional signal of aggressive intentions in male–male
contests stabilized by receiver-imposed retaliation costs. 相似文献
6.
Some mate choice theories propose that only male signals that are honest and condition-dependent can be stable, while another
hypothesis states that males evolve signals that exploit the sensory system of females. However, sensory traps might evolve
into honest signals if they are differentially costly for males. We tested whether a pre-existing sensory bias for food chemicals
explained chemosensory preferences of female Iberian rock lizards for male scents. We manipulated hunger levels of females
and found that food-deprived females had increased chemosensory responses to chemical stimuli from both invertebrate prey
and femoral secretions of males, but not to control water. Further tests suggested that cholesta-5,7-dien-3-ol (provitamin
D3), a lipid found in both prey and males’ scent, may be one of the chemicals eliciting these responses. Moreover, hungry females
spent more time on scent marks of males that had experimentally increased cholesta-5,7-dien-3-ol than on scent marks of males
alone, whereas for control females this effect was not significant. We suggest that preexisting sensory bias for essential
nutrients (i.e., provitamin D) may be the origin of similar female responses to male chemicals. However, previous studies
have suggested that the allocation of these chemicals to ornaments is costly and only high quality males can afford it. Therefore,
preexisting sensory bias for essential nutrients may further allow the evolution and maintenance of honest sexual displays. 相似文献
7.
Does female aggression prevent polygyny? An experiment with pied flycatchers (Ficedula hypoleuca) 总被引:1,自引:0,他引:1
The female aggression hypothesis states that resident females may be able to prevent polygyny by behaving aggressively towards
intruding females. A critical test of the hypothesis is to provide prospecting females with a choice between displaying mated
males some of which have initial mates with artificially reduced levels of aggressiveness. Here we present a mate choice experiment
on pied flycatchers Ficedula hypoleuca. The species is a cavity nester, and resident females were prevented from behaving aggressively by enclosing them within
their own nestboxes: narrowing the entrance hole so that they could not escape but could still let their head out and have
some contact with their mate. This treament had only a minor influence on male behaviour. We studied whether the experimental
males were better able to attract a new female than a control group of mated males. Four predictions from the female aggression
hypothesis were supported. (1) Mating success of control males was positively related to the distance between their primary
and secondary territory. (2) For experimental males, mating success was unrelated to interterritorial distance. (3) Experimental
males had higher mating success than control males when the interterritorial distance was short but (4) not when it was long.
Experimental males had much lower mating success than unmated males, as would be expected if prospecting females are able
to discover male mating status from cues other than visits by primary females to their mates' secondary nest sites.
Received: 5 January 1998 / Accepted after revision: 30 December 1998 相似文献
8.
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
9.
Sexual cannibalism particularly before mating is costly for the male victim but also for the female aggressor if she risks
remaining unmated. The aggressive spillover hypothesis explains the persistence of this behavior as a maladaptive side effect
of positive selection on aggressiveness in a foraging context. The hypothesis predicts that the occurrence of sexual cannibalism
is explained by female aggressiveness but is not related to male phenotype or behavioral type. An alternative hypothesis invokes
sexual selection and makes the opposite prediction namely that sexual cannibalism is an expression of female choice and should
hence mainly target males of low quality. We tested the above hypotheses on a sexually dimorphic nephilid spider Nephilengys livida, known for male monopolization of females via genital damage, female genital plugging, and mate guarding, by staging mating
trials during which we recorded mating behaviors and occurrences of pre- and postcopulatory cannibalism. We did not restrict
assessment of aggressiveness to the mating and foraging context but also included aggression against same sex conspecifics.
To assess female personalities, i.e., consistent individual differences in behavior including aggressiveness, we repeatedly
tested them for intra-sex aggression, voracity towards prey, locomotory activity, and boldness. Females exhibited consistent
differences in intra-sex aggressiveness, latency to attack prey, and boldness. Aggressive females had shorter latencies to
attack prey and were more active than non-aggressive ones. In contrast to the predictions of the aggressive spillover hypothesis,
females that were aggressive towards prey and towards other females were not more likely to attack a male than non-aggressive
females. In support of the mate choice hypothesis, less aggressive males were more likely attacked and cannibalized than more
aggressive ones. This hints at sexual selection for aggressiveness in males and raises the question of mechanisms that maintain
variation in male aggressiveness. 相似文献
10.
Adeline Loyau Michel Saint Jalme Robert Mauget Gabriele Sorci 《Behavioral ecology and sociobiology》2007,61(7):1043-1052
According to the differential investment hypothesis, females paired with attractive mates are expected to invest more in the
current reproduction relative to females paired with unattractive males. We experimentally tested this hypothesis in the peafowl
(Pavo cristatus) by providing females with males that differed in sexual attractiveness. In agreement with the differential allocation hypothesis,
females paired with more ornamented males laid larger eggs, and deposited higher amounts of testosterone into the egg yolk,
independently of the sex of the embryo. These results show that the association between paternal phenotype and offspring quality
could arise via a differential maternal investment. They also suggest that, if ornamented males do transmit good genes to
the progeny, the maternal differential investment can amplify the effect of such good genes on the offspring fitness. 相似文献
11.
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
12.
George W. Uetz David L. Clark J. Andrew Roberts Meghan Rector 《Behavioral ecology and sociobiology》2011,65(4):753-761
For visual signaling to be effective, animal signals must be detected and discriminated by receivers, often against complex
visual backgrounds with varying light levels. Accordingly, in many species, conspicuous visual displays and ornaments have
evolved as a means to enhance background contrast and thereby increase the detection and discrimination of male courtship
signals by females. Using video playbacks, we tested the hypothesis that visual courtship displays and leg decorations of
male Schizocosa ocreata wolf spiders are more conspicuous against complex leaf-litter backgrounds. Video exemplars of courting males with manipulated
leg tufts were superimposed on different backgrounds (complex leaf litter in sun or shade, featureless gray background) and
presented to female spiders. Females were more likely to orient to males presented against lighter backgrounds (litter in
sun, gray) than the darker ones (litter—shade). Males with larger tufts were also more likely to be detected, as latency to
orient was shortest for enlarged and longest for removed tufts. Latency of females to approach was shorter against lighter
backgrounds, and approach latency was longest for males without tufts. Female receptivity scores were significantly greater
for males against lighter backgrounds, and males with larger tufts had higher scores. These results suggest that both complexity
and light level of display backgrounds affect the detection of male visual courtship signals by females and that aspects of
the male phenotype may increase chances of detection (and receptivity) against visually complex backgrounds. 相似文献
13.
Richard N. C. Milner Michael D. Jennions Patricia R. Y. Backwell 《Behavioral ecology and sociobiology》2011,65(7):1419-1424
Non-independent mate selection occurs when the choice behavior of a female is altered by the interactions between other females
and males. In the fiddler crab Uca mjoebergi, males court mate-searching females by waving their one greatly enlarged claw. When a female approaches a male, he initiates
high-intensity waving. We conducted one natural mate choice experiment and two mate choice experiments using custom-built
robotic crabs. We show that the decision of one female to approach a group of males increases the probability that another
female will approach and visit a male from the same group. We suggest that this behavior is best explained by the ‘stimulus
enhancement’ hypothesis, where the presence of a female near a group of males makes them more likely to be detected by other
females due to an increase in male display rate. 相似文献
14.
Animals adjust their antipredator behavior according to environmental variation in risk, and to account for their ability
to respond to threats. Intrinsic factors that influence an animal’s ability to respond to predators (e.g., age, body condition)
should explain variation in antipredator behavior. For example, a juvenile might allocate more time to vigilance than an adult
because mortality as a result of predation is often high for this age class; however, the relationship between age/vulnerability
and antipredator behavior is not always clear or as predicted. We explored the influence of intrinsic factors on yellow-bellied
marmot (Marmota flaviventris) antipredator behavior using data pooled from 4 years of experiments. We hypothesized that inherently vulnerable animals
(e.g., young, males, and individuals in poor condition) would exhibit more antipredator behavior prior to and immediately
following conspecific alarm calls. As expected, males and yearlings suppressed foraging more than females and adults following
alarm call playbacks. In contrast to predictions, animals in better condition respond more than animals in below average condition.
Interestingly, these intrinsic properties did not influence baseline time budgets; animals of all ages, sexes, and condition
levels devoted comparable amounts of time to foraging prior to alarm calls. Our results support the hypothesis that inherent
differences in vulnerability influence antipredator behavior; furthermore, it appears that a crucial, but poorly acknowledged,
interaction exists between risk and state-dependence. Elevated risk may be required to reveal the workings of state-dependent
behavior, and studies of antipredator behavior in a single context may draw incomplete conclusions about age- or sex-specific
strategies. 相似文献
15.
Status signals are traits that advertise an individual’s competitive abilities to conspecifics during aggressive disputes.
Most studies of status signals in birds have focussed on melanin-based plumage signals, but recent research shows that carotenoid-based
signals may also play a role in aggressive signaling. We assessed the relative importance of melanin- and carotenoid-based
plumage patches as agonistic signals in a small passerine, the golden whistler (Pachycephala pectoralis). Display signals in male golden whistlers include an unpigmented white throat patch, a carotenoid-based yellow breast and
nape band, and a melanin-based black chin-stripe. We found that only the white throat patch was correlated with contest-related
attributes. Males possessing large throat patches defended larger territories and commenced breeding earlier. When caged males
with either experimentally reduced, or unmanipulated throat patches were presented to conspecifics, those with experimentally
reduced patches attracted less aggression from male subjects. Focal males also responded faster to caged males with throat
patches similar in size to their own, suggesting that they may assess relative throat patch size before engaging in aggressive
encounters. Females did not discriminate between “reduced” or “control” treatments. Our data strongly suggest that only the
unpigmented throat patch functions as a status signal. As this signal is unlikely to have significant development costs, honesty
may be maintained through social costs. 相似文献
16.
Five hypotheses have been proposed to explain polygyny in the red-winged blackbird (Agelaius phoeniceus). We categorized the hypotheses into three groups based on female preference for unmated versus monogamously mated males:
(1) the “polygyny threshold” model, “sexy son” hypothesis and the “asynchronous settlement” model, which assume that females
prefer unmated males to mated males on breeding situations of homogeneous quality; (2) the “neutral mate choice” hypothesis,
which assumes that females have no preference; and (3) the “cooperative female choice” model, which assumes that females prefer
monogamously mated males to unmated males. We tested the direction of female preference in two field experiments. In both
experiments, newly settling females were given a choice of two adjacent territories, one defended by an unmated male and the
other by a monogamously mated male. Male mating status was randomized with respect to the variation in territory quality and
male quality. Early in the breeding season, significantly more females settled with the unmated males than with the mated
males. Although more females settled with the unmated males than with the mated males late in the breeding season, the difference
was no longer significant. Female settlement late in the season appeared to be related to the tenure of the resident females:
the new females avoided territories where the resident females were in early stages of their nesting, but settled on territories
where the resident females were in late stages. The pattern of female settlement shows that females prefer unmated males to
mated males. The preference is consistent with the polygyny threshold model, sexy son hypothesis and the asynchronous settlement
model, and inconsistent with the neutral mate choice hypothesis and the cooperative female choice model. For this reason,
the latter two hypotheses are unlikely to explain the occurrence of polygyny in our population of red-winged blackbirds.
Received: 1 December 1994 / Accepted after revision: 28 October 1995 相似文献
17.
Jill M. Goldstein Glen E. Woolfenden Jack P. Hailman 《Behavioral ecology and sociobiology》1998,44(1):15-22
Prebreeders of the Florida scrub-jay (Aphelocoma coerulescens) are less likely to be found on their natal territories with a same-sex stepparent than with parents or an opposite-sex stepparent.
We tested two models that had been proposed to account for this sexual asymmetry. The dominance hypothesis states that stepparents
perceive same-sex prebreeders as competitors, primarily for a mate, so behave aggressively toward them. The pair-formation
hypothesis states that prebreeders remain home to pair eventually with the opposite-sex stepparent. Predictions from these
two models were tested by analyses from a quarter-century of records on a study population at Archbold Biological Station
and by new behavioral field observations at the Station. Results clearly rejected the latter and strongly supported the former
hypothesis. No prediction from the pair-formation hypothesis was confirmed: no pairing by a prebreeder of either sex has ever
occurred with a stepparent; remaining home was equally frequent in age-one males with stepmothers and genetic mothers, and
in females with stepfathers and genetic fathers; and the same results were found in age-two prebreeders. By contrast, the
data strongly supported the dominance hypothesis. Field data showed higher aggression rates by stepfathers to male prebreeders
and stepmothers to female prebreeders than by parents to their same-sex genetic offspring. Fewer age-one males remained home
with a stepfather than with the genetic father, and the same was found for age-one females with a stepmother and genetic mother;
at age two, the effect occurred only in female prebreeders. The two hypotheses make different predictions about prebreeders
with two stepparents versus with both parents, thus providing a critical test. The dominance hypothesis correctly predicted
decreased duration at home by age-one males and females; data for age-two females were in the direction of predicted difference
but not significant; and, as in other tests, no effect was found for age-two males. We propose that age-two male prebreeders
remain home despite elevated aggression from stepfathers because these prebreeders retain the possibility of budding from
or inheriting the natal territory.
Received: 16 July 1997 / Accepted after revision: 26 June 1998 相似文献
18.
Surface glycoproteins serve as mate- and gamete-recognition molecules in some marine animals such as rotifers and sea urchins.
We investigated the role of contact chemoreception of surface glycoproteins in mate recognition, mate-guarding, and spermatophore
transfer in the marine harpacticoid Tigriopus japonicus Mori. Adult males accurately distinguished immature females from a pool of mixed-sex juveniles, and their behavior towards
both live and dead females is described. A survey of the binding sites of twelve lectins to the surface of juvenile and adult
females, and adult males demonstrated localized lectin-binding at sites considered important in mating behavior of each sex/age
class. Treating adult males with the Triticum vulgaris lectin sharply inhibited normal mate recognition and guarding behavior, as did the monosaccharide glucosamine. Treatment
of males with protease and detergents destroyed their mate-guarding behavior without affecting swimming behavior. These results
suggest that protein receptors on the antennules of the males detect glycoprotein signals on the surface of females, recognizing
carbohydrate moieties of glycoproteins to identify appropriate partners for guarding or mating. Surface glycoproteins may
function as a common mechanism of sexual communication in many marine zooplankters.
Received: 6 May 1997 / Accepted: 14 September 1997 相似文献
19.
Fluctuating asymmetry (FA) can indicate developmental instability in bilaterally symmetric organisms, and studies have shown
that the degree of asymmetry in male secondary sexual characters influences female mate choice in a number of taxa. In male
Schizocosa ocreata wolf spiders, conspicuous tufts of bristles on the forelegs are a critical component of visual courtship signals, which appear
to play a role in female mate choice. Previous studies have shown that females exhibit reduced receptivity to males with regenerative
asymmetry, a consequence of leg loss and regeneration that causes males to be grossly asymmetric with respect to this important
signaling character. We provide data on the occurrence of FA in the tufts of S. ocreata, and examine further the influence of asymmetry on female mate choice. The distribution of tuft area asymmetry values from
a sample of field-collected males was normal, with a mean value of zero, indicating true FA. For a subset of males measured
directly after field collection and prior to feeding, tuft asymmetry was significantly negatively correlated with measures
of body size (body length) and condition (abdomen volume/cephalothorax width). Receptivity responses of females to visual
signals from live males of similar size varied with the degree of asymmetry in male tufts. Since FA covaries with male body
size and condition, which may also influence behavioral vigor, we used video image manipulation to alter the degree of asymmetry
in tufts of a courting male while holding size and condition constant. Asymmetry treatments represented values within the
range of natural FA variation as well as more extreme values characteristic of regenerative asymmetry. With the confounding
effects of male size, condition, and behavior held constant, female spiders exhibited reduced receptivity responses to all
experimental asymmetric video images relative to a control video stimulus. There were no differences in the frequency of female
receptivity among the various asymmetry treatments, suggesting that discrimination against asymmetry in conspecific male signal
characters is not simply a rejection of extreme phenotypes. Results suggest that asymmetry in a key male secondary character
used in visual signaling, independent of any concomitant behavioral or size factor, is an important criterion in mate choice.
Received: 26 February 1998 / Accepted after revision: 12 September 1998 相似文献
20.
Impressive variation in egg colouration among birds has puzzled evolutionary biologists for a long time. The most frequently
studied selective forces moulding egg colouration—predation and brood parasitism—have either received little empirical support
or may play a role in only a minority of species. A novel hypothesis has suggested that egg colour may be significantly influenced
by sexual selection. Females may deposit a blue-green pigment biliverdin into eggshells instead of using it for themselves
as a powerful antioxidant. By this handicap, females may signal their quality to males, which are then hypothesized to increase
their paternal effort. We experimentally tested the hypothesis in the collared flycatcher (Ficedula albicollis), a species laying blue-green eggs. We cross-fostered clutches between nests to disentangle effects of female/territory quality
and egg colour on paternal effort and nestling quality. The results supported two assumptions of sexual signalling through
egg colour hypothesis: Blue pigment seems to be a limited resource for females, and female quality is positively correlated
with the intensity of the blue-green colour. However, we did not find support for the main prediction of the hypothesis, as
male parental effort parameters (feeding frequencies to nestlings and intensity of nest defence) were unrelated to egg colour.
We discuss possible reasons for the discrepancy between our results and previous correlative analyses that supported the hypothesis
that blue egg colour may be a postmating, sexually selected signal in females. 相似文献