Low-quality Mates Research Articles

Mutual mate choice and its benefits for both sexes

In mating interactions, it is common in nature for both sexes to choose simultaneously. However, this mutual mate choice and its consequences for progeny has received relatively little study; an approach where both male and female condition is manipulated is thus desirable. We compared both sexes’ preferences in Tenebrio molitor beetles when individual condition varied (healthy vs infected with a fungus), and observed the direct benefits of those preferences. We predicted that: (a) females and males in good condition would prefer high quality mates; (b) preferences would be weaker when the choosing individual is in poor condition (and thus less selective given, for example, time and energetic constrains); and, (c) high quality mates would lay a larger number of total eggs and/or viable eggs than low quality mates. We found that both males and females in good condition were not more likely to choose mates that were also in good condition. However, poor-condition animals were more likely to prefer similar quality animals, while high-condition animals did not necessarily prefer mates of similar condition. Choosing sick males or females had a negative impact on egg number and viability. Our results suggest a non-adaptive mate choice in this species. Possibly, a deteriorated condition may drive individuals to invest more in attracting mates, because their chances of surviving the infection are very low. However, we do not discount the possibility that the fungus is manipulating individuals to increase its transmission during mating.

Choice of high-quality mates versus avoidance of low-quality mates.

Research in sexual selection assumes that individuals attempt to choose high-quality mates, and that sexual signals evolve to indicate high quality. But it may often be more important to instead discriminate and avoid low-quality mates, thus reducing the likelihood of large penalties in fitness. We show, using simulations, that avoidance of low-quality mates (i.e., rejecting low-quality and accepting either high- or medium-quality mates) evolves in socio-ecological circumstances such as monogamy with moderate opportunities for choice, costly choice, or abundant low-quality mates. We also show that this strategy is qualitatively different from choosing high-quality mates (i.e., preferring high-quality over medium- and low-quality mates). Rather than selecting signals that distinguish high- from low- and medium-quality mates, avoiding low-quality mates selects for signals or cues attuned at discriminating low-quality mates from the remaining (e.g., low-cost signals, absence of signaling mistakes). This may help explain the high diversity of sexual signals in nature, and their high evolutionary turnover with frequent losses and replacements (rather than reductions/increases of the same signal) over evolutionary time.

Listening to male song induces female field crickets to differentially allocate reproductive resources

Differential investment in offspring by mothers is predicted when there is substantial variation in sire quality. Whether females invest more resources in the offspring of high-quality mates (differential allocation, DA) or in the offspring of low-quality mates (reproductive compensation, RC) is not consistent in the literature and both effects can be predicted by theoretical models. In the field cricket, Grylluspennsylvanicus Burmeister, 1838 (Orthoptera: Gryllidae: Gryllinae), females are attracted more to calling songs of high-quality males than to those of low-quality males. We tested whether females invest reproductive resources differentially based on perceived mate quality. We manipulated female perception of male quality by allowing virgin females to approach a speaker broadcasting either high- or low-quality calling song (high or low calling effort respectively), and then mated them with a randomly chosen male that had been rendered incapable of calling. In the week following mating, females exposed to high-quality calling song gained less weight, laid more embryos, and laid larger embryos than females exposed to low-quality calling song, although only the first of these effects was statistically significant. These results support the DA hypothesis and suggest that females invest their reproductive output based on a trait (calling effort) that is an honest indicator of male quality.

One’s Better Half: Romantic Partners Function as Social Signals

Four studies tested the hypotheses that (1) romantic partners function as hard-to-fake signals of status and (2) men are concerned about signaling their status to both other men and to other women. In study 1, participants rated the status of an individual (gender remained neutral) who was described as attending a party with either a high-quality good (watch, car, mate) or a low-quality good. Participants rated the high-quality signaler as possessing more status than the low-quality signaler. Importantly, the high-quality mates functioned similarly to other high-quality material goods. In study 2, participants rated the status, niceness, and competence of men with high-quality mates and similarly described me with low-quality mates. Participants consistently rated the men with high-quality mates as possessing more status than similarly described men with low-quality mates. In study 3, we had only men rate that status of men with high-quality, average-quality, and low-quality mates. Men consistently rated other men with high-quality mates as possessing more status than similarly described men with low-quality mates. Finally, in study 4, we tested whether men signal high-quality mates predominantly to other men or to other women. Results supported the hypothesis that men are more concerned about signaling the quality of their mate to other men than to other women. We conclude with a discussion of the implications of these findings.

The ability to gain matings, not sperm competition, reduces the success of males carrying a selfish genetic element in a fly

Females are expected to avoid low-quality males fathering their offspring. X chromosome meiotic drive (XCMD) makes males very low-quality mates. XCMDs are X chromosomes that, in males, cause the failure of all Y chromosome sperm, so all functional sperm carry the driving X and produce daughters. This transmission advantage can allow the XCMD to spread through populations. However, XCMD males typically have low fertility, are very poor at sperm competition, only produce daughters, and bear low fitness alleles associated with XCMD. This imposes significant costs on females that mate with these males. Recently, several studies have shown that females can reduce the risk of their offspring inheriting XCMDs by mating with multiple males (polyandry), as XCMD males typically lose out to normal males in sperm competition. Hence it has been suggested that increased polyandry may be likely to evolve whenever a costly XCMD is common in a population, and that polyandry may be a key factor in preventing XCMDs spreading through populations. We tested this by examining the fruit fly Drosophila subobscura, in which females are known to mate only once in European populations where XCMDs are absent. However, in North African populations an XCMD, referred to as ‘SRs’, occurs. If the association between XCMDs and polyandry is true, then these North African populations should have evolved polyandry. However, we found no evidence of polyandry in North African D. subobscura populations. Instead, we found some evidence that males that carry SRs are slightly less successful at gaining matings in noncompetitive situations. These results show that polyandry does not necessarily evolve in response to the presence of harmful X chromosome drive. With both sperm competition and female choice both being unlikely to substantially reduce the success of XCMD in D. subobscura, the factors that prevent SRs spreading through these populations remain mysterious.

Haploid, diploid, and triploid--discrimination ability against polyploid mating partner in the parasitic wasp, Bracon brevicornis (Hymenoptera: Braconidae).

Because the quality of mating partners varies, females of several taxa have evolved the ability to discriminate against low-quality mates. Although males in the Hymenoptera are usually haploid, diploid males may occur in species with complementary sex determination. Diploid males are almost always sterile in most of the species studied so far. They are thus of very low quality as mating partners, especially when females mate only once in life. We hypothesize that hymenopteran females might have evolved the ability to discriminate against infertile diploid males and avoid mating with them. To test this hypothesis, we studied diploid male fitness in the parasitoid wasp Bracon brevicornis Wesmael (Hymenoptera: Braconidae) by measuring survival rate and fertility and then estimated their chances of actually mating with a female. Flow cytometry was used to determine the ploidy level of wasps. The fitness costs of mating a diploid male are indeed high in this species: only 15% were able to sire daughters, of which 97% were triploid and hardly able to produce viable offspring. In contrast to the hypothesis of unsuitable mate discrimination though, no evidence was found for increased rejection of diploid males by females. Male discrimination against an unsuitable partner did also not occur: triploid females elicited the same intensity of courtship behavior in males than did diploid ones.

Sound source localization in noise: Open-loop and closed-loop tests with Cope’s gray treefrog (Hyla chrysoscelis)

Event Abstract Back to Event Sound source localization in noise: Open-loop and closed-loop tests with Cope’s gray treefrog (Hyla chrysoscelis) Michael S. Caldwell1 and Mark A. Bee1, 2* 1 University of Minnesota, Department of Ecology, Evolution and Behavior, United States 2 University of Minnesota, Graduate Program in Neuroscience, United States At breeding choruses, female frogs must assess and locate a calling male among a background of competing sounds from other signalers and abiotic sources. In many ways, this task is analogous to the human 'cocktail party problem', where a partygoer struggles to follow the speech of a single interlocutor among many noisy guests. In masking noise, many animals show increased response thresholds and poorer performance in sound discrimination tasks, which potentially result in increased exposure to predators, increased energy expenditure, and selection of low-quality mates. It is often suggested that these effects are due, in part, to impaired sound localization in noise. While studies of human subjects demonstrate clear effects of masking noise on sound localization abilities, we know much less about how noise affects source localization in non-human (specifically, non-mammalian) animal models. Here, we report results from a study of sound source localization in frogs. In contrast to mammalian ears, frog ears are coupled through wide and open Eustachian tubes, making them inherently directional pressure-difference receivers. Using behavioral phonotaxis tests, we investigated the effects of masking noise, as well as noise level and signal level, on the localization of male mating calls by females of Cope’s gray treefrog in both open-loop and closed-loop listening conditions. Open-loop conditions assessed the fundamental localization acuity of the frog's auditory system; closed-loop conditions examined the frog's ability to use behavioral tactics to home in on a sound source or to improve localization by integrating information over time. By studying constraints faced by frogs localizing sounds in a complex acoustic environment, as well as adaptations for overcoming these challenges, we hope to uncover biologically diverse solutions to common problems of acoustic communication in noisy environments. Acknowledgements We thank Nate Buerkle for help testing frogs. This work is supported by NIDCD R01 5R01DC009582. Keywords: acoustic communication, chorus, closed-loop, cocktail party problem, Frog, open-loop, Sound Localization Conference: Tenth International Congress of Neuroethology, College Park. Maryland USA, United States, 5 Aug - 10 Aug, 2012. Presentation Type: Poster Presentation (see alternatives below as well) Topic: Communication Citation: Caldwell MS and Bee MA (2012). Sound source localization in noise: Open-loop and closed-loop tests with Cope’s gray treefrog (Hyla chrysoscelis). Conference Abstract: Tenth International Congress of Neuroethology. doi: 10.3389/conf.fnbeh.2012.27.00181 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 28 Apr 2012; Published Online: 07 Jul 2012. * Correspondence: Dr. Mark A Bee, University of Minnesota, Department of Ecology, Evolution and Behavior, St. Paul, United States, mbee@umn.edu Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Michael S Caldwell Mark A Bee Google Michael S Caldwell Mark A Bee Google Scholar Michael S Caldwell Mark A Bee PubMed Michael S Caldwell Mark A Bee Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Sex allocation and paternity in a cooperatively breeding passerine: evidence for the male attractiveness hypothesis?

Sex allocation theory predicts that female birds with high-quality mates will benefit from producing more sons, since sons will inherit their father’s superior traits and enjoy a great reproductive success, whereas females with low-quality mates will benefit from producing more daughters, since the variance in reproductive success among daughters is typically lower. The male attractiveness hypothesis may apply to extra-pair paternity (EPP) because socially monogamous females routinely mate with higher quality males outside the pair bond. We test these predictions using the Tibetan ground tit (Pseudopodoces humilis), a sexually monomorphic, socially monogamous, facultatively cooperative breeder. There was greater variation in actual reproductive success among males than females due to EPP. An excess of sons was detected for bi-parental (i.e., non-cooperative) broods wherein EPP was mainly sired by bi-parental males. The pattern was attributed to male-biased sex ratios produced for both EPP and within-pair offspring within the same broods. The reason for the latter case might be a random allocation of more offspring to sons by the potentially EPP-exposed females that have an inability to control fertilization by specific males. In cooperative broods where EPP mostly resulted from within-group helpers of presumed low-quality, as indicated by their failure in acquiring a social mate, there was a non-significant tendency for EPP offspring to be daughters and for within-pair offspring in the same broods to be unbiased. These results support the EPP-related male attractiveness hypothesis especially in terms of the overproduction of sons. Offspring produced through quasi-parasitism was unbiased towards either sex, suggesting a weak female choiceness with respect to the quality of host males.

Morphological and genetic predictors of parental care in the North American barn swallow Hirundo rustica erythrogaster

Sexually dimorphic traits often signal the fitness benefits an individual can provide to potential mates. In species with altricial young, these signals may also predict the level of parental care an individual is expected to provide to shared offspring. In this study, we tested three hypotheses that traditionally relate sexually dimorphic traits to parental care in two populations of North American barn swallows Hirundo rustica erythrogaster. The good parent hypothesis predicts a positive relationship between an individual's ornamentation and his or her care whereas the differential allocation (more care given by individuals when paired to high quality mates) and reproductive compensation (more care given by individuals when paired to low quality mates) hypotheses predict that an individual's level of parental investment is relative to the quality of their mate. Male and female North American barn swallows have colorful ventral feathers and elongated tail streamers, but there is evidence that ventral color, not tail streamer length, predicts measures of seasonal reproductive success. Accounting for the positive correlation between within‐pair feeding rates and other potentially confounding variables in all of our models, we found no support for the good parent hypothesis because in both males and females, traits shown to be under sexual selection did not predict feeding rates in either sex. However, our data reveal that male coloration, and not streamer length, predicted a female's provisioning rate to shared offspring (females fed more when paired with darker individuals) in two separate populations, supporting the differential allocation, but not the reproductive compensation hypothesis. Because genetic traits have also been shown to affect parental investment, we evaluated this variable as well and found that a male's paternity did not have significant effects on either male or female feeding rates. Overall, our results suggest that females do not pair with darker males in order to gain direct benefits in terms of his expected levels of parental care to shared offspring, but do themselves invest greater levels of care when paired to darker males. Further, our results are consistent with previous studies which suggest that ventral feather color, not streamer length, is a target of sexual selection in North American populations of barn swallow because females invested more in their offspring when paired to darker mates.

Reproductive investment when mate quality varies: differential allocation versus reproductive compensation.

Reproductive investment decisions form an integral part of life-history biology. Selection frequently favours plasticity in investment that can generate maternal effects on offspring development. For example, if females differentially allocate resources based on mate attractiveness or quality, this can create a non-genetic link between mate attractiveness and offspring fitness with potential consequences for ecological and evolutionary dynamics. It is therefore important to understand under what conditions differential investment into offspring in relation to male quality is expected to occur and the direction of the effect. Two opposite predictions, increased investment into offspring produced with high-quality mates (differential allocation (DA)) and increased investment with low-quality males (reproductive compensation (RC)) have been suggested but no formal theoretical treatment justifying the assumptions underlying these two hypotheses has been conducted to date. Here, we used a state-based approach to investigate the circumstances under which the variation in mate quality results in differential female investment into offspring and how this interacts with female energetic resource levels. We found that a pattern of increased investment when mating with high-quality mates (i.e. DA) was the most common optimal investment strategy for females in our model. By contrast, increased investment when mating with low-quality mates (i.e. RC) was predicted only when the relative impact of parental investment on offspring quality was low. Finally, we found that the specific pattern of investment in relation to male quality depends on female energetic state, the likelihood for future mating opportunities and the expected future distribution of mate quality. Thus, the female's age and body condition should be important factors mediating DA and RC, which may help to explain the equivocal results of empirical studies.

Mate inspection patterns in the female beaugregory damselfish (Stegastes leucostictus)

We observed female beaugregory damselfish (Stegastes leucostictus) as they interacted with males to see whether their movements fit the predictions of different mate-search models. We established high-quality and low-quality groups with low variance in breeding site quality and a medium-quality, high-variance breeding site group and compared focal observations of female nonforaging forays in each group. Only 8% of 137 forays monitored resulted in spawning events. Eighty-nine percent of the forays were less than 240 s and were within 7 m of the focal female’s territory. Average foray times and straight-line foray distances did not differ for females traveling between males in each group. Females entered high-quality breeding sites at a higher rate than low-quality sites and round-trip distances were also greatest in high-quality groups, indicating that females were following a more convoluted path. We interpret these results to mean that (a) female beaugregories separate the tasks of mate assessment and mate choice by conducting information-gathering forays between mating events, (b) forays are energetically costly and therefore usually short in duration and overall distance traveled, (c) information collection takes approximately the same time for high-quality and low-quality mates, but (d) females will alter their foray patterns in high-quality areas to collect additional information. These data are also consistent with the hypothesis that females optimize their search by employing a tiered process of assessment during information-gathering forays, first using an adjustable threshold to accept or reject each male based on his courtship and subsequently a fixed threshold to assess the quality of each breeding site.

No evidence of genetic benefits from extra-pair fertilisations in female sand martins (Riparia riparia)

Genetic parentage studies of socially monogamous birds reveal a widespread prevalence of extra-pair paternity. Variation in extra-pair paternity among individuals may depend on how different individuals benefit from extra-pair fertilisations and on the opportunity to pursue extra-pair copulations. A long-term study of sand martins (Riparia riparia) in Hungary allowed us to examine patterns of extra-pair fertilisations in a large colony of over 3,000 breeding pairs with many known age individuals. We used multi-locus DNA fingerprinting to determine whether extra-pair fertilisations occur when females are paired to (1) presumably low quality mates, or (2) genetically similar or dissimilar mates, and whether extra-pair fertilisations result in offspring of higher quality. Extra-paternal young were found in 38% of 47 broods and comprised 19% of 190 offspring. Males that lost paternity did not differ significantly from others in age or body condition. Social mates of broods containing extra-pair offspring did not differ in genetic similarity from pairs without extra-pair offspring. Furthermore, there was no significant difference in body condition between extra-pair young and their maternal half-siblings. We were unable to assign paternity and therefore cannot exclude the possibility that extra-pair males differed from the within-pair males they cuckolded, in age, body condition or genetic similarity with the female. We found a positive relationship between paternity losses and breeding density, suggesting that low breeding density may constrain opportunities for seeking extra-pair copulations.

Sperm numbers vary between inter- and intra-population matings of the grasshopper Chorthippus parallelus

Comparing the reproductive output of intra- and inter-population matings is the most common way to assess whether post-mating reproductive isolation is caused by genetic incompatibilities. Such genetic incompatibility can however, only assume that the quantity of the post-mating signals involved does not differ between intra- and inter-population matings. This assumption may not be true because sexual selection predicts reduced mating effort towards low-quality mates and in many circumstances, allopatric partners are low-quality mates. Post-mating efforts may, therefore, be reduced in inter- compared to intra-population matings. Here, I test this crucial assumption by studying variation in one post-mating trait, sperm number, in crosses of two parapatric grasshopper populations. In both populations, males transferred fewer sperm to allopatric than sympatric females. If such plasticity with respect to population is common in other post-mating traits, differences between inter- and intra-population crosses may be more frequently caused by differences in sperm number rather than gamete incompatibility. Additionally, I found that sperm numbers declined less rapidly in the female storage organ of allopatric than sympatric females but its rate differed markedly between populations. This is discussed with respect to female adaptations to male traits.

A possible non-sexual origin of mate preference: are male guppies mimicking fruit?

In most animals, the origins of mating preferences are not clear. The "sensory-bias" hypothesis proposes that biases in female sensory or neural systems are important in triggering sexual selection and in determining which male traits will become elaborated into sexual ornaments. Subsequently, other mechanisms can evolve for discriminating between high- and low-quality mates. Female guppies (Poecilia reticulata) generally show a preference for males with larger, more chromatic orange spots. It has been proposed that this preference originated because it enabled females to obtain high-quality mates. We present evidence for an alternative hypothesis, that the origin of the preference is a pleiotropic effect of a sensory bias for the colour orange, which might have arisen in the context of food detection. In field and laboratory experiments, adult guppies of both sexes were more responsive to orange-coloured objects than to objects of other colours, even outside a mating context. Across populations, variation in attraction to orange objects explained 94% of the inter-population variation in female mate preference for orange coloration on males. This is one of the first studies to show both an association between a potential trigger of a mate-choice preference and a sexually selected trait, and also that an innate attraction to a coloured inanimate object explains almost all of the observed variation in female mate choice. These results support the "sensory-bias" hypothesis for the evolution of mating preferences.

Female spadefoot toads compromise on mate quality to ensure conspecific matings

When high-quality conspecifics resemble heterospecifics, females may be unable to engage effectively in both species recognition (identification of conspecifics) and mate-quality recognition (identification of high-quality mates). Consequently, females that engage primarily in mate-quality recognition may risk heterospecific matings, and females that engage primarily in species recognition may risk mating with low-quality mates. I examined the evolutionary consequences of this conflict between species and mate-quality recognition in spadefoot toads, Spea multiplicata. I compared mate preferences and the fitness consequences of these preferences in spadefoot toad populations that did and did not overlap with congeners. In non-overlapping populations, S. multiplicata females preferred an extreme call character resembling that of heterospecifics, and they had more eggs fertilized. In overlapping populations, S. multiplicata females preferred those call characteristics that were closest to the norm for their population, and they did not receive the benefit of enhanced fertilization success. Thus, S. multiplicata females appear to trade off species and mate-quality recognition, such that those co-occurring with heterospecifics forgo the benefits of high-quality matings to ensure conspecific matings. These results suggest that the interaction between species and mate-quality recognition may influence mate choice decisions in important and nonintuitive ways. Key words: mate choice, mate-quality recognition, species recognition, Scaphiopus couchii, Spea bombifrons, Spea multiplicata. [Behav Ecol 11:220–227 (2000)]

Comparative evidence for a positive association between divorce and extra-pair paternity in birds

Although most bird species are socially monogamous, they show a large variation in both divorce rate and the proportion of extra-pair paternity (EPP). Recently, adaptive explanations of avian monogamy have considered divorce and EPP as related behavioural strategies by which individuals paired with low quality mates can improve their breeding status within ecological and time constraints. It has been suggested that, at both the intra- and inter-specific levels, divorce rate should be associated with the frequency of EPP. Divorce and EPP could coexist as alternative strategies whose relative frequencies would depend on ecological conditions, resulting in a negative association between the two phenomena. Or, they can be seen as synergistic tactics co-varying with variation in mate quality between populations or species and are thus positively associated. Here, applying two different comparative methods: the comparison of independent linear contrast and the pairwise comparison of closely related taxa, we show that high rates of divorce are positively associated with high rates of extra-pair paternity in socially monogamous species of birds, even when controlling for survival rate as a potentially confounding variable. This constitutes the first comparative evidence for a relation between divorce and adultery in animals. We discuss this result in relation to recent hypotheses on the adaptiveness of divorce and extra-pair copulations in birds and natural variation in mate quality among populations or species. The pattern found is most consistent with the hypothesis that birds may divorce to gain a better breeding position, but alternatives cannot be fully ruled out.

Mate Choice and Lepidopteran Mating Behavior

Our understanding of the evolution and adaptive features of animal mating behavior has dramatically improved in recent years as our understanding of the process of sexual selection and its consequences have been refined. Darwin (1871) first proposed sexual selection as the evolutionary process that gave rise to bizarre and seemingly maladaptive traits such as the tail of the peacock and the brilliant colors of male butterflies. He reasoned that the negative effects of these traits on male survivorship were outweighed by their positive effects on male reproductive success during courtship with females and competition with other males for access to females. Ronald Fisher (1958) later-1930-pointed out that in order for this process to have begun in the first place there had to have been some reproductive advantage to those females who chose for mates, males with certain traits. He argued that those traits used by females in mate selection must be correlated with high quality genes possessed by the male or high quality paternal care or investments the male has to offer. More recently, Robert Trivers (1972) explained that females are generally expected to be more selective than males because they usually make a larger investment in each offspring than does the male, and therefore have more to lose by copulating with low quality mates. In other words, a female's reproductive success may be viewed as being limited more by her ability to acquire nutrients for the production and care of her offspring rather than by the number of matings she obtains. Such a limitation would, in turn, favor care in the selection of mates. Males, on the other hand, typically invest little other than sperm in each of their offspring. Therefore their reproductive success is limited primarily by the number of copulations they can obtain rather than the number of gametes they can produce. Males, then, are generally expected to search out females and to mate willingly with any receptive female. The mating behavior of the Lepidoptera generally conforms to these expectations. After eclosion, females attract males either visually (butterflies and some moths) or chemically (most moths). A male searching for females locates one by using these signals, flies towards her, and courts her by barraging her with visual, chemical, and tactile signals. The male's chemical signals are typically produced by specialized structures such as hairpencils or patches of specialized scales on the wings. Females are generally passive during courtship but, if receptive, those of some species assume postures that facilitate the act of coupling. Copulation lasts from less than one to more than several hours after which the male departs and renews his search for mates. The female, on the other hand, (after copulation) ceases to emit sex attractants and becomes refractory to mating attempts by males. Her behavior becomes concentrated on efforts to locate oviposition sites and