Differences In Female Responses Research Articles

Familiarity and social relationships in degus (Octodon degus)

AbstractDegus (Octodon degus) are a highly gregarious species of caviomorph rodent native to South America. Kinship does not appear to play a role in degu social structure, and alloparenting is often observed between unrelated females. We hypothesize that female degus readily establish new, cooperative peer relationships. Here, we examined changes in dyadic behavior as individuals became more familiar, testing the prediction that interactions between female strangers would quickly resemble those of cagemates. Adult degus underwent a several week series of 20 min “reunion” social exposures, interleaving reunions with initial strangers and, as a control, familiar cagemates. Males showed initially higher levels of interaction with strangers that converged with cagemate levels over experience. Females could be split into two groups: those that consistently interacted more with strangers (SC‐HIGH) and those that did not (SC‐LOW); however, unlike males, the higher interaction levels observed between strangers did not change with familiarity. Following 10 reunion sessions female strangers were housed together to create “new cagemates.” Even after co‐housing, SC‐HIGH (but not SC‐LOW) females continued to interact more with the relatively unfamiliar peer than their prior cagemate, particularly in face‐to‐face and rear‐sniffing interactions. A final set of reunions with new strangers found that individual differences in female responses to social novelty were preserved. These results reveal sex differences in the rules relating familiarization to social relationships in degus, and that female predispositions toward cooperation may be due to inherent responses to new individuals more than to how they negotiate relationships over time.

Brain size affects responsiveness in mating behaviour to variation in predation pressure and sex ratio.

Despite ongoing advances in sexual selection theory, the evolution of mating decisions remains enigmatic. Cognitive processes often require simultaneous processing of multiple sources of information from environmental and social cues. However, little experimental data exist on how cognitive ability affects such fitness-associated aspects of behaviour. Using advanced tracking techniques, we studied mating behaviours of guppies artificially selected for divergence in relative brain size, with known differences in cognitive ability, when predation threat and sex ratio was varied. In females, we found a general increase in copulation behaviour in when the sex ratio was female biased, but only large-brained females responded with greater willingness to copulate under a low predation threat. In males, we found that small-brained individuals courted more intensively and displayed more aggressive behaviours than large-brained individuals. However, there were no differences in female response to males with different brain size. These results provide further evidence of a role for female brain size in optimal decision-making in a mating context. In addition, our results indicate that brain size may affect mating display skill in male guppies. We suggest that it is important to consider the association between brain size, cognitive ability and sexual behaviour when studying how morphological and behavioural traits evolve in wild populations.

Innate olfactory responses of female and male parasitoid Apanteles taragamae Viereck (Hymenoptera: Braconidae) toward host plant infested by the cucumber moth Diaphania indica Saunders (Lepidoptera: Crambidae)

ABSTRACTThe behavioural responses of Apanteles taragamae, a larval parasitoid of the cucumber moth Diaphania indica, to the volatiles of cucumber plants was investigated in a four-arm olfactometer. Females and males were given a choice between several odour sources that included (1) clean air, (2) uninfested, (3) host-infested, and (4) mechanically damaged cucumber plants. Females and males showed different preferences for volatiles emanating from these plants. Females responded significantly longer to the volatiles from uninfested plants than clean air, and to host-infested plants than uninfested plants. There were no significant differences in female responses to the volatiles from mechanically damaged and uninfested plants. Males responded significantly longer to clean air rather than uninfested plants. The volatiles from both uninfested and host-infested cucumber plants may play important roles in host habitat location of A. taragamae females.

Genetic variation in the effect of monoamines on female mating receptivity and oviposition in the adzuki bean beetle, Callosobruchus chinensis (Coleoptera: Bruchidae).

BackgroundFemale mate choice after mating is a strong force in sexual selection and could lead to coevolution of mating traits between the sexes. How females of different genotypes respond to substances in the male ejaculate should be mediated by females’ mate choices. Monoamines regulate animal physiology and behavior, including the post-mating behavior of females of the adzuki bean beetle, Callosobruchus chinensis (Coleoptera: Bruchidae). This study examined differences in females’ response to four monoamines (dopamine, octopamine, tyramine, serotonin) between strains from different populations of C. chinensis.ResultsInjection with either octopamine or tyramine, two kinds of monoamines significantly reduced female receptivity in two strains with low remating frequencies. None of the four monoamines reduced female receptivity in one strain with high remating frequencies. However, all monoamines reduced it in another strain with high remating frequencies. Oviposition was activated by tyramine on days 1–5 or by serotonin on days 4 and 5 in the two strains with low remating frequencies, but only on day 1 or day 4 in the strains with high remating frequencies.ConclusionThese differences in female response to monoamines, especially tyramine and serotonin, correspond with results of previous studies. They indicate differences in female response to male substances that reduce receptivity and activate oviposition. These findings suggest relationships between the differences in female response to male substances among populations and mutations in the pathways of monoamine biosynthesis or transmission, which in turn determine female mate choice in response to male substances.

Responses of Diaphorina citri (Hemiptera: Psyllidae) to Conspecific Vibrational Signals and Synthetic Mimics

Abstract Mate-seeking in Diaphorina citri Kuwayama, a vector of the economically damaging huanglongbing citrus disease, typically includes male—female duetting behaviors. First, the male calls by beating his wings at ≈170–250 Hz, producing vibrations that are transmitted along the host tree branches to the female. If receptive, she immediately replies, helping to direct the searching male toward her. The duetting and searching continues until the male locates the female. Males and females are similar in size and produce wingbeat vibrations with similar temporal and spectral patterns. A study of male and female responses to playbacks of recorded and synthetic mimics of different vibrational signals on citrus plants was conducted to better understand the range of signals to which D. citri respond and potentially to co-opt or disrupt their vibrational communication. In general, both sexes responded well to a variety of 0.3–0.5-s signals that included multiple harmonics of ≈200-Hz wingbeatfrequency chirps up to ≈1,400 Hz (where a chirp is a sine wave tone that sweeps across a narrow range of frequencies). There were only minor differences in female responses to signals containing different relative amplitudes of such chirps, and males readily located sources that played these multipleharmonic signals. The results are discussed in relation to mating-signal selectivity and the potential for developing automated methods to trap male D. citri by using vibrational signals.

Alien Egg Retrieval in Common Pochard: Do Females Discriminate between Conspecific and Heterospecific Eggs?

Incorporation of unrelated eggs into a clutch by incubating females (egg retrieval), which has an obvious adaptive value when female retrieves her own egg, seems to be also a part of the reproductive tactics related to brood parasitism. In open nesting waterfowl, the parasitic egg remains frequently outside the nest bowl after the parasitic event. Using time-lapse video recorders, we described experimentally the behavioural reaction of the common pochard (Aythya ferina) females towards an egg lying beside the nest. We tested whether the females discriminate between conspecific and heterospecific eggs (brown chicken eggs). All 16 experimental females retrieved both conspecific and heterospecific eggs. We found no apparent differences in female responses towards either egg type. The retrieval of alien eggs can be a result of an imperfect recognition ability of the female, anti-predation defence, or sophisticated tactic related to the brood parasitism. The last explanation seems to be less likely due to impe...

Gender-Based Analysis of Work Trip Mode Choice of Commuters in Suburban Montreal, Canada, with Stated Preference Data

Transportation literature suggests that men and women differ in their commuting patterns and in their propensity to switch between travel options. In North America, it is expected that women will have an increasing impact on travel demand. As such, differences in female responses to travel demand management strategies are likely to become increasingly important as governments try to curtail travel demand. This paper uses a 1994 stated preference survey of suburban commuters in Montreal, Canada, to determine whether there is evidence for differences between men and women in the factors that affect work trip choices, to quantify those differences, and to suggest what the differences imply for travel demand management in the future in Montreal. The main conclusions of this paper are as follows. First, women and men should be modeled separately for work trip mode choice. Second, three main differences appear from the econometric models: women are less likely to choose public transit than men; women are more likely to choose to rideshare; and women are less time-sensitive in regard to commuting than men are.

Gender-Based Analysis of Work Trip Mode Choice of Commuters in Suburban Montreal, Canada, with Stated Preference Data

Transportation literature suggests that men and women differ in their commuting patterns and in their propensity to switch between travel options. In North America, it is expected that women will have an increasing impact on travel demand. As such, differences in female responses to travel demand management strategies are likely to become increasingly important as governments try to curtail travel demand. This paper uses a 1994 stated preference survey of suburban commuters in Montreal, Canada, to determine whether there is evidence for differences between men and women in the factors that affect work trip choices, to quantify those differences, and to suggest what the differences imply for travel demand management in the future in Montreal. The main conclusions of this paper are as follows. First, women and men should be modeled separately for work trip mode choice. Second, three main differences appear from the econometric models: women are less likely to choose public transit than men; women are more l...

Phylogenetic influence on mating call preferences in female túngara frogs,Physalaemus pustulosus

We evaluated how various phylogenetic models for estimating ancestral characters can influence studies of behavioural evolution. Previously we used a single model of evolution to estimate the values of call characters at ancestral nodes for thePhysalaemus pustulosusspecies group and some close relatives (Ryan & Rand 1995,Science,269, 390–392). We then synthesized these ancestral calls and measured the females’ responses to such calls in phonotaxis experiments. We repeated the above procedure to determine the sensitivity of these results and conclusions to various models used to estimate the ancestral call characters. We asked whether: (1) different models gave different call estimates for the same nodes; (2) different call estimates at the same node were perceived as different by females; and (3) differences in female responses influenced previous conclusions. We used seven different models that varied in at least one of the following parameters: tree topology (bifurcating versus pectinate in-group trees), algorithms (local squared-change versus squared-change parsimony), tempo (gradual or punctuated evolution), and outgroups (two or three outgroup taxa used). Although different models often gave different call estimates for the same node, these different estimates often were not perceived as different by the females. These data reinforce our previous conclusions that: (1) the range of female preferences exceeds the known variation of the conspecific call; (2) females do not discriminate between the conspecific call and the call of their most recent ancestor; and (3) female responses may be context dependent, given that females differ in their responses to the same signal variation in discrimination and recognition experiments.

Ethnic Differences in Female Responses to Work in the Cold

Ethnic Differences in Female Responses to Work in the Cold