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141.
Daniela M. Simeonovska-Nikolova 《Journal of Ethology》2007,25(1):41-48
The social interactions between Apodemus agrarius and A. flavicollis, and their behavioral responses to conspecific and heterospecific odors, were studied in male–male and female–female interspecific
dyadic encounters, and an attraction–avoidance test was used in order to clarify the behavioral mechanisms which control their
relationships in wild populations. The experiments were carried out at the beginning and at the end of the breeding season—in
spring and in autumn. In spring the aggressiveness was higher than in autumn. Males of both species showed attraction to conspecific
odors from the opposite sex, while the females were indifferent. In autumn both males and females displayed attraction to
conspecific odors from the same sex. However, mice of both species showed avoidance to heterospecific odors from the same
and the opposite sex in spring, and indifference to heterospecific odors from the same and the opposite sex in autumn. Based
on these findings, it could be assumed that the patterns of social interactions and responses to conspecific and heterospecific
odors undergo seasonal changes in their life cycle. Probably the avoidance response to heterospecific odors could serve as
a spacing mechanism to avoid aggressive encounters between A. agrarius and A. flavicollis in syntopic habitats during the breeding period. 相似文献
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145.
We investigated reproductive regulation in male Rufous-winged Sparrows, Aimophila carpalis, a Sonoran Desert passerine that breeds after irregular summer rains. Field and captive data demonstrate that increased photoperiod stimulates testicular development in March and maintains it until early September. Free-living birds caught in July and placed on captive long days (16L: 8D) maintained developed testes for up to 7 months, and free-living birds caught in September, during testicular regression, redeveloped testes when placed on captive long days, indicating that these birds were still photosensitive. Captive birds on long days maintained testicular development when exposed to temperatures mimicking those occurring during regression in free-living birds. In free-living birds, testicular development was observed during spring and summer, but unless this was associated with rainfall, breeding (indicated by juveniles) did not occur. Large increases in plasma luteinizing hormone (LH) in free-living males were correlated with heavy rainfall in July/August, when the birds bred, and in November, when they did not breed. In captive birds, plasma LH concentrations were unresponsive to photoperiodic changes, but may have responded to social cues. Plasma prolactin concentrations were directly correlated with photoperiod in free-living birds, but an effect of photoperiod on prolactin secretion was not seen in captive birds. It is concluded that male Rufous-winged Sparrows use long photoperiods to stimulate and maintain testicular development, but exposure to long photoperiods does not terminate breeding by inducing absolute photorefractoriness. The specific timing of reproductive behaviors is apparently determined by elevated plasma LH coinciding with long day stimulated gonad development. 相似文献
146.
Baldauf SA Thünken T Frommen JG Bakker TC Heupel O Kullmann H 《International journal for parasitology》2007,37(1):61-65
Many parasites with complex life cycles increase the chances of reaching a final host by adapting strategies to manipulate their intermediate host's appearance, condition or behaviour. The acanthocephalan parasite Pomphorhynchus laevis uses freshwater amphipods as intermediate hosts before reaching sexual maturity in predatory fish. We performed a series of choice experiments with infected and uninfected Gammarus pulex in order to distinguish between the effects of visual and olfactory predator cues on parasite-induced changes in host behaviour. When both visual and olfactory cues, as well as only olfactory cues were offered, infected and uninfected G. pulex showed significantly different preferences for the predator or the non-predator side. Uninfected individuals significantly avoided predator odours while infected individuals significantly preferred the side with predator odours. When only visual contact with a predator was allowed, infected and uninfected gammarids behaved similarly and had no significant preference. Thus, we believe we show for the first time that P. laevis increases its chance to reach a final host by olfactory-triggered manipulation of the anti-predator behaviour of its intermediate host. 相似文献
147.
Myrmarachne assimilis, an ant-like (myrmecomorphic) jumping spider (Araneae, Salticidae) from the Philippines, is a Batesian mimic of Oecophylla smaragdina, the Asian weaver ant. Salticids are well known for their acute eyesight and the elaborate vision-based display behaviour
they adopt during encounters with conspecific individuals, but most salticids are not myrmecomorphic. Despite its unusual
morphology, M. assimilis adopts display behaviour during intraspecific interactions that is similar to the display behaviour of more typical salticids.
The specificity with which M. assimilis deploys display behaviour is investigated and provides insights into this mimic’s ability to differentiate, by sight alone,
between models, conspecific individuals and prey. During each standardized test, an adult M. assimilis female was in a large cage along with a small transparent glass vial, a stimulus animal being enclosed in the vial such that
potential optical cues, but not potential chemical cues, were available to the tested M. assimilis individual. Depending on the test, the stimulus animal was another adult M. assimilis female, a house fly (prey) or an ant (Camponotus sp. or O. smaragdina). Only the conspecific female consistently elicited display from M. assimilis, implying that M. assimilis is a Batesian mimic that can, when relying on vision alone, discriminate between conspecific individuals, models and prey.
Received 12 June 2006; revised 22 September 2006; accepted 26 September 2006. 相似文献
148.
Konstantinos Kostarakos Jürgen Rheinlaender Heiner Römer 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2007,193(11):1115-1123
We examined peripheral and central nervous cues underlying the ability of the bushcricket Leptophyes punctatissima to orient to elevated and depressed sound sources broadcasting the female acoustic reply. The peripheral spatial directionality
of the ear was measured physiologically using monaural preparations of an auditory interneuron (T-fibre). In the azimuth,
maximal interaural intensity differences of 18 dB occur between ipsi- and contralateral stimulation. With increasing elevation
or depression of the sound sources, IIDs decrease systematically and reach zero with the source exactly above or below the
preparation. Bilateral, simultaneous recordings of the activity of the pair of interneurons allowed determining the binaural
discharge differences which occur in response to the extremely short (1 ms) female reply. These discharge differences are
large (four action potentials/stimulus) and reliable in the azimuth with lateral stimulation, and decrease gradually with
more frontal stimulation. With elevation and depression of sound sources these differences again decrease to one action potential/stimulus
at 60° or 75° elevation, and lateral stimulus angles of about 60°. We also calculated the reliability with which a receiver
could correctly determine the location of the sound source. We discuss these quantitative measures in relation to the spatial
phonotactic behaviour of male L. punctatissima. 相似文献
149.
Foraging behaviour of Lysiphlebus testaceipes was studied in a Y-tube olfactometer. Naïve females responded to the Aphis gossypii/eggplant complex on which they had been reared, but did not show a preference for this aphid/plant complex over an uninfested eggplant, an eggplant that had been damaged by the aphid or an A. gossypii/okra complex. Females that had been allowed to forage on the A. gossypii/eggplant complex before being tested in the olfactometer showed a strong preference for an uninfested eggplant over an uninfested okra plant and for the A. gossypii/eggplant complex over an A. gossypii/okra complex, indicating that they had learned to associate eggplant-derived volatiles with host availability. When females that had been reared on the A. gossypii/eggplant complex were tested after foraging experience on the A. gossypii/okra complex, they did not show a preference for either complex, suggesting that they still retained a memory of the cues associated with the complex on which they had been reared. The efficiency of L. testaceipes as a biological control agent in peri-urban vegetable production, such as the Cuban organoponics system, potentially could be improved by producing and releasing females behaviourally primed to prefer specific host/plant complexes. 相似文献
150.
Female mating preferences are often based on more than one cue.In empirical studies, however, different mate choice cues aretypically treated separately ignoring their possible interactions.In the current work, we studied how male body size and sizeof the male's nest jointly affect mate preferences of femalesand gobies, Pomatoschistus minutus. The females were givena binary choice between males that differed either in body sizeor size of their nest or both. We found that neither body sizenor size of the nest alone affected male attractiveness, buttogether these 2 cues had a significant effect. Specifically,large males were more popular among females when they had alarge nest than when they occupied a small nest. The resultssuggest that if interaction effects between multiple mate choicecues are not considered, there is a danger of ignoring or underestimatingthe importance of these cues in sexual selection by female choice. 相似文献