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11.
How does a foraging honeybee come to prefer a color or odor paired with the large of two amounts of sucrose solution to a color or odor paired with the smaller amount? One hypothesis is that the attractiveness of a color or odor is based on the strength of its association with the taste of sucrose, which increases with the duration of concurrent color-taste or odor-taste stimulation. Another hypothesis is that the attractiveness of a color or odor is based on association with the afferent consequences of feeding, which are different for the two amounts. Both hypotheses were tested in experiments on proboscis-extension conditioning, a technique that provides better control of stimulation than is possible in work with free-flying foragers. In Experiments 1–3, which were designed to test the first hypothesis, an odor that accompanied the ingestion of sucrose on training trials was found to elicit extension of the proboscis when subsequently it was presented alone, but the duration of concurrent stimulation had no significant effect on the probability or persistence of the response. In Experiments 4 and 5, which were designed to test the second hypothesis, an odor that immediately followed the ingestion of sucrose on training trials failed to elicit extension of the proboscis when subsequently it was presented alone. The results support neither hypothesis. 相似文献
12.
David B. Ritland 《Evolution; international journal of organic evolution》1991,45(4):918-934
Batesian and Müllerian mimicry relationships differ greatly in terms of selective pressures affecting the participants; hence, accurately characterizing a mimetic interaction is a crucial prerequisite to understanding the selective milieux of model, mimic, and predator. Florida viceroy butterflies (Limenitis archippus floridensis) are conventionally characterized as palatable Batesian mimics of distasteful Florida queens (Danaus gilippus berenice). However, recent experiments indicate that both butterflies are moderately distasteful, suggesting they may be Müllerian comimics. To directly test whether the butterflies exemplify Müllerian mimicry, I performed two reciprocal experiments using red-winged blackbird predators. In Experiment 1, each of eight birds was exposed to a series of eight queens as “models,” then offered four choice trials involving a viceroy (the putative “mimic”) versus a novel alternative butterfly. If mimicry was effective, viceroys should be attacked less than alternatives. I also compared the birds' reactions to solo viceroy “mimics” offered before and after queen models, hypothesizing that attack rate on the viceroy would decrease after birds had been exposed to queen models. In Experiment 2, 12 birds were tested with viceroys as models and queens as putative mimics. The experiments revealed that (1) viceroys and queens offered as models were both moderately unpalatable (only 16% entirely eaten), (2) some birds apparently developed conditioned aversions to viceroy or queen models after only eight exposures, (3) in the subsequent choice trials, viceroy and queen “mimics” were attacked significantly less than alternatives, and (4) solo postmodel mimics were attacked significantly less than solo premodel mimics. Therefore, under these experimental conditions, sampled Florida viceroys and queens are comimics and exemplify Müllerian, not Batesian, mimicry. This compels a reassessment of selective forces affecting the butterflies and their predators, and sets the stage for a broader empirical investigation of the ecological and evolutionary dynamics of mimicry. 相似文献
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14.
Classical Conditioning-Induced Changes in Low-Molecular-Weight GTP-Binding Proteins in Rabbit Hippocampus 总被引:1,自引:0,他引:1
T. J. Nelson J.-V. Sanchez-Andres B. G. Schreurs D. L. Alkon 《Journal of neurochemistry》1991,57(6):2065-2069
Classical conditioning of Hermissenda, involving paired light-rotation events, results in a 30-35% decrease in the levels of a 20-kDa G protein (cp20). To test whether a similar protein exists in vertebrates, rabbits were trained to associate a tone with periorbital electrical stimulation and G proteins were analyzed by photoaffinity labeling with [alpha-32P]GTP-azidoanilide. A 20-kDa G protein similar to cp20 decreased by 36% in the hippocampus of rabbits subjected to paired tone and electrical stimulation, but not in unpaired controls. Learning-specific decreases were also found in the amount of ras protein. 相似文献
15.
Interactions of two tubicolous, deposit-feeding polychaetes, Clymenella torquata (Leidy) and Polydora ligni Webster, with a filter-feeding bivalve, Gemma gemma (Totten), were examined to test the functional group hypothesis that small, filter-feeding bivalves with large young should attain high densities with tube-builders of any trophic mode because the large young escape predation by tube-builders. The prediction was not supported by Polydora and Gemma, since the two species have not been reported to coexist in high densities in nature. In laboratory experiments, Polydora reduced recruitment and adult survival of Gemma relative to a control. Polydora preyed on juvenile clams and reduced the time which adult clams had their siphons in the feeding position, relative to a control.For Clymenella and Gemma, the functional group hypothesis made the correct prediction (i.e. the two species are reported to coexist in high densities in nature), but for the wrong reason. The size of Gemma's offspring is not related to the intensity of Clymenella predation. Clymenella does not ingest Gemma since the worm does not usually feed from the zone occupied by the clam. In contrast to Polydora, Clymenella did not reduce the time which clams fully extend and open their siphons relative to a control. In laboratory experiments Clymenella increased adult bivalve growth, survival after one year, and recruit size after one month. Clam life history characteristics were similar in the Clymenella and Clymenella plus Polydora treatments because the number of surviving Polydora was reduced by a negative interaction with Clymenella.The tube-builders had different effects on the filter-feeder, Gemma, because these tube-building species differ in feeding position, diet and behavior. Thus, the functional group hypothesis was too general to predict and explain the species interactions and distributions. 相似文献
16.
Food rewards were given contingent upon the performance of one of three natural responses in adult male pigtail macaques:
scratching, yawning, and the facial expression “protruded lips.” Scratching rapidly increased in frequency when it was followed
by food, as did variability in form of scratching and one form in particular, using the feet. The facial expression was resistant
to the conditioning procedures. Yawning increased in frequency when followed by food, with extinction and reconditioning procedures
confirming the establishment of the conditioned response. This is the first report of the conditioning of yawning in primates.
Together, the results contribute to the literature on the differential conditionability of different classes of behavior,
and suggest the possibility that macaques can voluntarily display “reflexive” acts for social goals. 相似文献
17.
Albino rabbits were subjected to Pavlovian (classical) conditioning and extinction of concomitant heart rate and eyeblink responses. Sixty minutes before each of three extinction sessions animals were treated with 5 or 20 μg/kg of deamino-dicarba-arginine-8-vasopressin or saline. Vasopressin treatment delayed extinction of bradycardiac conditioned responses but did not affect concomitant eyeblink conditioned responses. It was concluded that classically conditioned autonomic responses may be useful tools for studying the effects of peptides on learning. 相似文献
18.
Hadj S. Aoued Soma Sannigrahi Sarah C. Hunter Nandini Doshi Zakia S. Sathi Anthony W. S. Chan Hasse Walum Brian G. Dias 《Genes, Brain & Behavior》2020,19(4)
Salient sensory environments experienced by a parental generation can exert intergenerational influences on offspring. While these data provide an exciting new perspective on biological inheritance, questions remain about causes and consequences of intergenerational influences of salient sensory experience. We previously showed that exposing male mice to a salient olfactory experience, like olfactory fear conditioning, resulted in offspring demonstrating a sensitivity to the odor used to condition the paternal generation and possessing enhanced neuroanatomical representation for that odor. In this study, we first injected RNA extracted from sperm of male mice that underwent olfactory fear conditioning into naïve single‐cell zygotes and found that adults that developed from these embryos had increased sensitivity and enhanced neuroanatomical representation for the odor (Odor A) with which the paternal male had been conditioned. Next, we found that female, but not male offspring sired by males conditioned with Odor A show enhanced consolidation of a weak single‐trial Odor A + shock fear conditioning protocol. Our data provide evidence that RNA found in the paternal germline after exposure to salient sensory experiences can contribute to intergenerational influences of such experiences, and that such intergenerational influences confer an element of adaptation to the offspring. In so doing, our study of intergenerational influences of parental sensory experience adds to existing literature on intergenerational influences of parental exposures to stress and dietary manipulations and suggests that some causes (sperm RNA) and consequences (behavioral flexibility) of intergenerational influences of parental experiences may be conserved across a variety of parental experiences. 相似文献
19.
20.
Saeed Bahrami Moqadam Ahamd Saleh Asheghabadi Farzaneh Norouzi Hamed Jafarzadeh Ali Khosroabadi Afshin Alagheband Ghazal Bangash Negar Morovatdar Jing Xu 《仿生工程学报(英文版)》2021,18(6):1344-1357
Lack of temperature sensation of myoelectric prosthetic hand limits the daily activities of amputees.To this end,a non-invasive temperature sensation method is proposed to train amputees to sense temperature with psychophysical sensory substitution.In this study,22 healthy participants took part besides 5 amputee participants.The duration time of the study was 31 days with five test steps according to the Leitner technique.An adjustable temperature mug and a Peltier were used to change the temperature of the water/phantom digits to induce temperature to participants.Also,to isolate the surround-ings and show colors,a Virtual Reality(VR)glass was employed.The statistical results conducted are based on the response of participants with questionnaire method.Using Chi-square tests,it is concluded that participants answer the experiment significantly correctly using the Leitner technique(P value<0.05).Also,by applying the"Repeated Measures ANOVA",it is noticed that the time of numbness felt by participants had significant(P value<0.001)difference.Participants could remember lowest and highest temperatures significantly better than other temperatures(P value<0.001);furthermore,the well-trained amputee participant practically using the prosthesis with 72.58%could identify object's temperature with only once time experimenting the color temperature. 相似文献