Showing papers in "Journal of Comparative Psychology in 1987"
TL;DR: The biparental care system of Peromyscus californicus affords an opportunity to develop a broader, more complete view of parent-offspring relations.
Abstract: Most knowledge of parent-offspring relations in mammals is derived from studies of mother-infant interactions. Male parental care has been less well studied. We explored maternal and paternal behavior of the California mouse, Peromyscus californicus. Six pairs of parents and their young were videotaped continuously for 12 hours/day, on alternate days from Days 1 to 31 postpartum. Males exhibit all parental activities and to the same extent as displayed by mothers, except lactation. Male parental behavior begins on the day of birth. Mothers and fathers spend substantial and equivalent amounts of time in the nest and in physical contact with pups throughout lactation. Males devote more time than females to licking pups, although females engage in more pup anogenital licking. Mothers nurse for at least 4 weeks, and fathers and mothers both build nests and carry young. The biparental care system of Peromyscus californicus affords an opportunity to develop a broader, more complete view of parent-offspring relations.
214 citations
TL;DR: Effects of lesions to the medial preoptic area, castration, and testosterone replacement on instrumental and unconditioned sexual behavior in male rats are studied and motivational and performance effects of these neuroendocrine manipulations are discussed.
Abstract: We studied effects of lesions to the medial preoptic area (POA), castration, and testosterone replacement on instrumental and unconditioned sexual behavior in male rats. We achieved instrumental measures of sexual motivation by training males to work for an estrous female, presented in an operant chamber under a second-order schedule of reinforcement. POA lesions abolished mounts, intromissions, and ejaculation but did not disrupt instrumental responses, investigation of the female, or abortive mounting attempts. Castration abolished attempts to copulate and also caused a marked decrease in instrumental responses. Testosterone resulted in the prompt reinstatement of instrumental responses and more gradual recovery of unconditioned sexual behavior. We discuss these results in terms of the motivational and performance effects of these neuroendocrine manipulations.
209 citations
TL;DR: The manufacture and use of tools in captive groups of tufted capuchin monkeys (Cebus apella) are described, providing further evidence that capuchins possess extensive manipulative propensities and emphasize the significance of the normal social environment in the full expression of these propensity.
Abstract: In this report we describe the manufacture and use of tools in captive groups of tufted capuchin monkeys (Cebus apella). Apparatus designed to accommodate probing and sponging behaviors were introduced into the monkeys' home cage with materials provided for fashioning tools. In one group of 9 capuchins, 6 were successful in manufacturing and using probes, and in a second group, 4 of 5 capuchins were successful in using probes, and 3 in manufacturing them. In a follow-up study with the larger group of capuchins, 8 monkeys were successful in manufacturing sponging tools from paper towels. Our studies provide the first report of spontaneous manufacture of tools in any group of monkeys. The tool-using and manufacturing behaviors observed in the capuchins were similar in form, function, and ontogeny to those that have previously been reported for chimpanzees. Our results provide further evidence that capuchins possess extensive manipulative propensities and emphasize the significance of the normal social environment in the full expression of these propensities. Finally, we spell out some directions future research could take in developing an understanding of the psychological characteristics underlying toolrelated behaviorc in diverse species.
189 citations
TL;DR: The present research demonstrates that the critical ratio function for the budgerigar is not only different from other vertebrates but alsoDifferent from other birds.
Abstract: Operant conditioning and a psychophysical tracking procedure were used to measure auditory thresholds for pure tones in quiet and in noise for seven species of small birds--the budgerigar, canary, cockatiel, European starling, song sparrow, swamp sparrow, and the zebra finch. Audibility curves are roughly similar among the seven birds, with the maximum sensitivity between 2 and 5 kHz and poorer sensitivity outside this narrow region. Critical ratios (signal-to-noise ratio at masked threshold) were calculated from pure-tone thresholds in noise. Except for the budgerigar, the critical ratio functions of all birds increase at the rate of 3 dB/octave. This pattern is typical of that observed in most vertebrates. Critical ratios in the budgerigar, on the other hand, decrease gradually from 0.5 kHz to 2.8 kHz and increase dramatically above 2.8 kHz. The present research demonstrates that the critical ratio function for the budgerigar is not only different from other vertebrates but also different from other birds.
177 citations
137 citations
120 citations
TL;DR: It is concluded that the second-order paradigm provides a means of distinguishing between the effects of neuroendocrine manipulations on incentive motivational and performance variables underlying the expression of sexual behavior.
Abstract: We describe a novel procedure for measuring instrumental sexual behavior in the male rat by using a second-order schedule of presentation of sexual reinforcement, an estrous female. Experimental assessment and validation of the paradigm have been achieved by examining (a) the importance of the conditioned stimulus in maintaining instrumental responding by measuring the effects of its omission during a test session, (b) the effects and motivational specificity on instrumental behavior of the postejaculatory refractory period (a period of sexual unarousability) and of satiety for food by measuring the impact of each manipulation on animals working for food and for a female, (c) the effects of replacing an estrous female with an anestrous one as the earned reward, and (d) the correlations between conditioned and unconditioned measures of sexual behavior. We conclude that the second-order paradigm provides a means of distinguishing between the effects of neuroendocrine manipulations on incentive motivational and performance variables underlying the expression of sexual behavior.
111 citations
TL;DR: It is found that rat fetuses discriminate between intraoral infusions of milk and lemon, exhibiting different levels and patterns of overall activity after infusion.
Abstract: We investigated sensory and behavioral responsiveness of the rat fetus. On Days 19, 20, or 21 of gestation, rat fetuses received intraoral infusions of a biologically important stimulus, milk, or a novel chemical stimulus, lemon. Using a technique to directly observe behavior in utero, we found that rat fetuses discriminate between intraoral infusions of milk and lemon, exhibiting different levels and patterns of overall activity after infusion. Milk was found to evoke a low magnitude, delayed increase in overall fetal activity from Day 19 through Day 21, whereas lemon evoked a high-magnitude, spiked pattern of activity that diminished from Day 19 to Day 21. Late in gestation these two stimuli elicited species-typical action patterns. Milk infusions elicited a stretch response much like the one shown by pups at the nipple; lemon infusions elicited face wiping typical of older pups and adults exposed to aversive gustatory stimuli.
100 citations
82 citations
TL;DR: Operant conditioning and multidimensional scaling procedures were used to study auditory perception of complex sounds in the budgerigar and showed that budgerIGars group vocal stimuli according to functional and acoustical categories.
Abstract: Operant conditioning and multidimensional scaling procedures were used to study auditory perception of complex sounds in the budgerigar. In a same-different discrimination task, budgerigars learned to discriminate among natural vocal signals. Multidimensional scaling procedures were used to arrange these complex acoustic stimuli in a two-dimensional space reflecting perceptual organization. Results show that budgerigars group vocal stimuli according to functional and acoustical categories. Studies with only contact calls show that birds also make within-category discriminations. The acoustic cues in contact calls most salient to budgerigars appear to be quite complex. There is a suggestion that the sex of the signaler may also be encoded in these calls. The results from budgerigars were compared with the results from humans tested on some of the same sets of complex sounds.
76 citations
TL;DR: The startle threshold of the albino Sprague-Dawley rat runs parallel to the curve of the hearing threshold, and only the head movement component of the startle response is elicited at threshold.
Abstract: The startle threshold of the albino Sprague-Dawley rat runs parallel to the curve of the hearing threshold. The difference between the startle and hearing threshold is 87 dB (SPL) at a background noise level of 75 dB (SPL). At 110 dB (SPL), the threshold has a range from 2 kHz to 50 kHz with a minimum at 10 kHz and a second minimum at 40 kHz. Amplitude and latency of the startle response are not only dependent on the sensation level of the acoustic stimulus but also on the frequency. At threshold, only the head movement component of the startle response is elicited.
TL;DR: The present results agree with earlier findings that chimpanzees will engage in drawing activities without training or reinforcement, and this behavior may reflect their intrinsic interest in exploratory and manipulative play.
Abstract: Three chimpanzees (Pan troglodytes) were provided with 18 different stimulus pages for drawing. The resulting 618 drawings were coded for drawn marks, and results were compared with early reports on ape drawing (Morris, 1962; Schiller, 1951) and with more recent systematic studies (Smith, 1973). The findings of the present study confirm Smith's observations of a tendency for the animals to draw closer to the center and toward the bottom of the page. No evidence for perceptual balancing was observed in drawings produced on pages with lateral figures, nor was any evidence for closure apparent with complex figures. The present results agree with earlier findings that chimpanzees will engage in drawing activities without training or reinforcement, and this behavior may reflect their intrinsic interest in exploratory and manipulative play.
TL;DR: A pigeon was trained to peck a small facsimile of a banana placed within its reach, to climb onto a box, to open a door, and to push a box toward targets to produce a humanlike solution to the problem.
Abstract: A pigeon was trained to peck a small facsimile of a banana placed within its reach, to climb onto a box, to open a door, and to push a box toward targets. When confronted with a new situation-the banana was placed out of reach, and the box was placed behind the door-the four repertoires came together rapidly to produce a humanlike solution to the problem. A tentative account of the performance is offered in terms of empirically validated principles.
TL;DR: As predicted, men avoided the treated stalls during the androstenol week only, and neither odor affected female stall selection, demonstrating a sex differential influence of the experimental odor.
Abstract: A natural secretion, 5 alpha-androst-16-en-3 alpha-ol (androstenol) is speculated to function as a spacing pheromone. The effect of the odor of androstenol on restroom-stall choices was investigated over a 5-week period. The first, third, and fifth weeks served as baselines against which the effect of androstenol or a control odor, 3 alpha-hydroxy-5 alpha-androstan-17-one (androsterone) could be evaluated. During the second and fourth weeks, half of the stalls in each restroom were treated with androstenol or androsterone, respectively. As predicted, men avoided the treated stalls during the androstenol week only, and neither odor affected female stall selection, demonstrating a sex differential influence of the experimental odor.
TL;DR: A new combination of operant conditioning and psychophysical scaling procedures was used to study auditory perception in a small bird, and budgerigars were much less responsive to pitch contour than were humans.
Abstract: A new combination of operant conditioning and psychophysical scaling procedures was used to study auditory perception in a small bird. In a same-different discrimination task, budgerigars learned to discriminate among pure tones that varied along one or more acoustic dimensions. Response latencies were used to generate a matrix of interstimulus similarities. Multidimensional scaling procedures were used to arrange these acoustic stimuli in a multidimensional space that supposedly reflects the bird's perceptual organization. For tones that varied in intensity, duration, and frequency simultaneously, budgerigars were much more sensitive to frequency changes. From a set of tones that varied only in intensity, it was possible to calculate the growth of loudness with intensity for the budgerigar. For tones that varied only in frequency, budgerigars showed evidence of an "acoustic fovea" for frequency change in the spectral region of 2-4 kHz. Budgerigars and humans also differed in their perceptual grouping of tone sequences that rise, fall, or remain constant in pitch. Surprisingly, budgerigars were much less responsive to pitch contour than were humans.
TL;DR: It was observed that the female darted more if communication were disrupted (i.e., female devocalized or male deafened).
Abstract: Both male and female rats vocalize ultrasonically during mating. Whereas male calls are known to facilitate female proceptive behavior, the female mating call has not been studied beyond spectrographic analysis. In this article, a series of experiments were done to examine the effects of the female's mating call on rat mating behavior. In the first experiment, females copulated with intact males before and after surgical devocalization. In the second experiment, intact females copulated twice with a male: once when they were able to hear and once when they were temporarily deafened with a medical ear mold. In the third experiment, tape recorded ultrasounds were placed in the presence of devocalized females while they were copulating with intact males. In the control condition, tape hiss was presented. In each experiment, it was observed that the female darted more if communication were disrupted (i.e., female devocalized or male deafened). Playback partially reduced darting to control levels. No other behavior was affected consistently across all experiments. Female calls might facilitate self-regulation of mating behavior, or they might focus the male's attention on her proceptive behaviors. It is also possible that the female calls could alter the stimulus properties of the male's behavior, indirectly affecting her own behavior.
TL;DR: The effect of having eaten a large meal (50% of body weight) on the defensive behavior of juvenile garter snakes (Thamnophis sirtalis) was investigated.
Abstract: The effect of having eaten a large meal (50% of body weight) on the defensive behavior of juvenile garter snakes (Thamnophis sirtalis)was investigated Twenty-five 10-wk-old snakes were tested for antipredator responses (strikes) directed toward a threatening stimulus (moving and nonmoving human hand) before and after having eaten a large worm segment Snakes directed significantly (p < 001) more strikes at both moving and nonmoving stimuli when tested 4 hr after feeding, but the number of snakes fleeing from the stimuli was not affected
TL;DR: It is suggested that the eye region may provide a primate with an important source of information, possibly information about intent, as well as other regions or combinations of regions of the dominant male in the group.
Abstract: Preferences for regions of the face were examined in four members of a hamadryas baboon (Papio hamadryas) group. Subjects were presented a series of photographic slides displaying various facial regions and combinations of regions of the dominant male in the group with the use of the method of paired comparison. An apparatus consisting of a two-slide screen/two-push-button arrangement permitted the baboons to control slide selection and viewing duration. Both duration and frequency of slide activation were recorded. Correlations of viewing durations among all subjects were significant (p less than or equal to .05). The eye region alone and in combination with other regions received significantly more attention than did all other regions or combinations. Frequency measures were not significant. The results support findings obtained with rhesus monkeys (Macaca mulatta) and suggest that the eye region may provide a primate with an important source of information, possibly information about intent.
TL;DR: The Belgian waterslager canary, selectively bred for loud, low-pitched song, has also developed poor high-frequency hearing.
Abstract: Canaries (Serinus canarius) of the Belgian waterslager strain from two different colonies were trained with operant techniques for audiometric testing. For both young and old birds, absolute thresholds in the middle- to high-frequency region of the audiogram were between 30 and 40 dB (SPL) higher than those of other song birds, including canaries of other strains. Thus the Belgian waterslager canary, selectively bred for loud, low-pitched song, has also developed poor high-frequency hearing.
TL;DR: Although the presence of the nonagouti allele cannot fully account for the behavioral differences between wild and domestic Norway rats, it may have facilitated the domestication of this species by improving ease of handling.
Abstract: The objective of the present study was to determine the extent to which the nonagouti pelage-color allele influences selected behaviors (including docility) of the wild Norway rat. Agouti and nonagouti (black) littermates were compared in tests for handling, open-field behavior, platform jumping, and response to a novel food item, all of which clearly differentiate wild and domestic rats. Nonagouti rats were significantly easier to approach, capture, and handle than their agouti sibs. However, differences between agouti and nonagouti rats for the other variables studied were not significant. Although the presence of the nonagouti allele cannot fully account for the behavioral differences between wild and domestic Norway rats, it may have facilitated the domestication of this species by improving ease of handling.
TL;DR: Results indicate that language experience and/or testing context affect feature salience for sign recognition and support the notion that there exists a higher order (general purpose) temporal pattern processor in dolphins in which visual as well as acoustic input is processed.
Abstract: Responses of Atlantic bottle-nosed dolphins (Tursiops Iruncatus) and of humans were collected and analyzed in order to determine the features required for recognition and discrimination of signs (hand signals) in an artificial gestural communication system. Subjects responded to systematically modified signs in which sign components were contrasted for competitive feature salience. One dolphin, with 6 years of training in the language, was shown these modified signs intermixed with normal signs in a linguistic, sentence-comprehension context. A second dolphin, familiar with action signs only and with no sentence-comprehension training, served as a nonlingual control. Human subjects were tested in two parallel tasks. The dolphin with signlanguage experience attended to (in order of importance) location, completed temporal pattern, gross motor motion, and direction of motion, as salient features. Fine motor motion, hand shape, and hand orientation were less salient. The non-sign-language dolphin attended to all sign features equally and was unaffected by temporal pattern changes. Humans tested in a linguistic context attended to (in order) gross motor motion, location, and an interaction of fine motor motion, hand shape, and hand orientation. Direction of motion and temporal pattern were not salient. Nonlinguistic-context humans attended to all sign features equally and were unaffected by temporal pattern changes. Results indicate that language experience and/or testing context affect feature salience for sign recognition. Results also support the notion that there exists a higher order (general purpose) temporal pattern processor in dolphins in which visual as well as acoustic input is processed. Two Atlantic bottle-nosed dolphins at the Kewalo Basin Marine Mammal Laboratory have been the subjects of ongoing research in cognition and sentence comprehension in two arbitrary and artificial languages (Herman, Richards, & Wolz, 1984). These two dolphins came from the west coast of Florida (were caught within one mile of each other), were approximately the same age when caught (aged 2 years, as judged from weight and length), and were subjected to the same procedures and treatments in the 8 years that they have been at the research laboratory. The most distinguishing difference in treatment between the two animals has been the nature of artificial language in which each has been trained. One language is acoustic and is based on computer-generated sounds. The second language is visual and is based on hand
TL;DR: Examination of the behavior of male-female dyads of both species interacting during 1-hr tests in large, familiar habitats containing defensible nest boxes, food, and water finds levels of aggression within pairs were low, compared with those seen during brief intrasexual encounters, whereas affiliative behaviors were high.
Abstract: Recent studies in our laboratory have suggested that monogamy may be the preferred mating system in the Djungarian hamster (Phodopus campbelli), whereas the available evidence for the closely related Siberian hamster (P. sungorus) does not show the same pattern. Here we examine the behavior of male-female dyads of both species interacting during 1-hr tests in large, familiar habitats containing defensible nest boxes, food, and water. Levels of aggression within pairs were low, compared with those seen during brief intrasexual encounters, whereas affiliative behaviors, such as sniffs, were high. P. campbelli scent marked more than twice as frequently as P. sungorus. Females of both species scent marked at a constant rate irrespective of their location in the habitat, whereas males scent marked at a higher rate in the female's home area. Two major features of the copulatory pattern differed between the two species: (a) The duration of the ejaculatory lock was five times longer in P. sungorus than in P. campbelli. (b) Both species had approximately the same number of mounts in each ejaculatory series, but the intromission/mount ratio was significantly higher in P. sungorus.
TL;DR: The development of head orientation to auditory stimulation was examined in rat pups at Postnatal Days 8, 11, 14, 17, and 20 and results indicate an earlier onset for orientation to high frequency sounds in the rat.
Abstract: The development of head orientation to auditory stimulation was examined in rat pups at Postnatal Days 8, 11, 14, 17, and 20. The animals were tested in a quiet environment with single bursts of 65 dB (SPL) broad-band noise. A reflexive head turn toward the sound was first seen on Postnatal Day 14 and subsequently on Days 17 and 20. This result demonstrates that the onset of directional auditory responses occurred between Day 11 and Day 14. The role of binaural cues in early sound orientation was examined in 17-day-old pups with monaural ligation of the external meatus. These animals were unable to localize a sound source and consistently turned toward the side of the unligated ear regardless of the position of the stimulus. Thus binaural cues were shown to be important for head orientation to sound in early development. In a separate study, head orientation to high and low frequency tone pips was examined. Directional responses were first seen on Day 12 for a 16-kHz tone and Day 14 for a 2-kHz tone. These results indicate an earlier onset for orientation to high frequency sounds in the rat.
TL;DR: The amount of water transfer from pups to mothers and fathers in the biparental California mouse, Peromyscus californicus, is determined by injecting 5, 10, 20, and 30-day-old pups with tritiated water and measuring the radioactive label in maternal and paternal plasma after 24 hr of interaction with their litter.
Abstract: Mammalian mothers provide water to their young via milk. Rodent mothers reclaim much of this water by licking the anogenital areas of their pups, stimulating reflexive urination, and consuming the pups' urine. Male rodents do not provide milk (hence water) to the young, but in some species male parents may nevertheless lick their pups. We determined the amount of water transfer from pups to mothers and fathers in the biparental California mouse, Peromyscus californicus, by injecting 5-, 10-, 20-, and 30-day-old pups with tritiated water and measuring the radioactive label in maternal and paternal plasma after 24 hr of interaction with their litter. On Days 5 and 10 mothers obtained more pup urine than did fathers. Parents consumed equivalent amounts of pup urine on Days 20 and 30. Mothers engaged in more pup anogenital licking than did fathers, which accounted for the difference in pup urine consumption. Salt appetite controls in part, pup anogenital licking in lactating rats (Gubernick & Alberts, 1983). Salt appetite was not implicated in the modulation of anogenital licking in the California mouse because the mice failed to display a salt appetite. Licking of young and urine consumption are not dependent solely on the bidirectional exchange of water between the dam and her offspring.