No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Stable individual differences on developmental tasks in young yellow-crowned parakeets, Cyanoramphus auriceps
Abstract
We report on stable individual differences in young yellow-crowned parakeets across 38 tasks of cognitive development on three scales involving object permanence, means-end relations, and spatial relations. Stable performance ranks on blocks of tasks emerged after 13 weeks in two groups of sibling parakeets, one hand-reared and the other parent-reared. Examination of subject characteristics, such as hatch order, sex, general activity level, avoidances, latencies, social status, and errors, showed no significant correlations with these performance ranks. Characteristic individual approaches to unstructured play activities (from a fourth scale) were consistent with individual behavioral differences seen on the structured cognitive tasks.
... Existing work demonstrates that there is variability both within and between parrot species in their performance on cognitive tasks (e.g., Funk and Matteson 2004;Liedtke et al. 2011;Pepperberg 2004;Gajdon et al. 2006). One potential factor that could explain within-species variation is cerebral lateralization or the degree to which cognitive processes are localized to one side of the brain (Rogers 1996). ...
... Almost all (92 %) of the parrots acquired the task, though individuals varied in their performance. Similar to other studies of psittacine cognition (e.g., Funk and Matteson 2004), there was no evidence of sex differences in performance. The strength of individuals' foot preferences had a significant influence on learning set acquisition, but did not influence cognitive flexibility. ...
Psittacines are generally considered to possess cognitive abilities comparable to those of primates. Most psittacine research has evaluated performance on standardized complex cognition tasks, but studies of basic cognitive processes are limited. We tested orange-winged Amazon parrots (Amazona amazonica) on a spatial foraging assessment, the Hamilton search task. This task is a standardized test used in human and non-human primate studies. It has multiple phases, which require trial and error learning, learning set breaking, and spatial memory. We investigated search strategies used to complete the task, cognitive flexibility, and long-term memory for the task. We also assessed the effects of individual strength of motor lateralization (foot preference) and sex on task performance. Almost all (92 %) of the parrots acquired the task. All had significant foot preferences, with 69 % preferring their left foot, and showed side preferences contralateral to their preferred limb during location selection. The parrots were able to alter their search strategies when reward contingencies changed, demonstrating cognitive flexibility. They were also able to remember the task over a 6-month period. Lateralization had a significant influence on learning set acquisition but no effect on cognitive flexibility. There were no sex differences. To our knowledge, this is the first cognitive study using this particular species and one of the few studies of cognitive abilities in any Neotropical parrot species.
... This does not mean, however, that more distantly related species are unsuitable -only that the tests must be adapted to enable comparison. For example, Funk (1996aFunk ( , 1996bFunk ( , 2002Funk & Matteson, 2004) investigated the development of yellow-crowned parakeets (Cyanoramphus auriceps) in several Piagetian domains and found consistent individual performance and a development pattern similar to that of human infants. Although the parakeets developed much faster, the precise timing of their development, resulting from various performance factors, is relatively unimportant. ...
Evolution involves developmental change. Species comparisons play an important role in comparative cognition because they can uncover common patterns and shared principles in cognitive evolution. Developmental studies reveal foundational elements of cognitive abilities and how they are constructed and integrated. Sensorimotor cognition is such a key element that forms the foundation for later-developing cognitive skills, yet little is known about its development in animals. This study uses 37 behaviors and tasks to investigate the development of Piagetian sensorimotor abilities in five young ravens (Corvus corax) from ages two to eleven weeks. Their developmental pattern largely mirrored that of twelve other bird and mammal species, albeit at a markedly accelerated rate. They reached the final sensorimotor stage, which to date has been shown only in great apes. The onset and sequence of sensorimotor development was identical for all species. Absolute number of neurons in the pallium and rest of brain was associated with achieving a higher stage across these species. This was not the case for absolute or relative brain mass, or number of neurons in the cerebellum or whole brain. We discuss the independent evolution of sensorimotor cognition and the importance of developmental pace and pattern therein. These findings show that the study of sensorimotor development is a useful tool for comparative cognition research.
... In this case, rearing history may have influenced the level of novel object apprehension in this highly neophobic species. It has, for example, been shown that handreared juvenile orange winged amazons and New Zealand parakeets approach novel objects faster than parent-reared birds (Fox & Millam, 2004;Funk, 2002;Funk & Matteson, 2004). Nevertheless, it is curious that the remaining subjects did not even leave their perches throughout most of the entire experiment (15 sessions of 30 minutes). ...
In primates, complex object combinations during play are often regarded as precursors of functional behavior. Here we investigate combinatory behaviors during unrewarded object manipulation in seven parrot species, including kea, African grey parrots and Goffin cockatoos, three species previously used as model species for technical problem solving. We further examine a habitually tool using species, the black palm cockatoo. Moreover, we incorporate three neotropical species, the yellow- and the black-billed Amazon and the burrowing parakeet. Paralleling previous studies on primates and corvids, free object-object combinations and complex object-substrate combinations such as inserting objects into tubes/holes or stacking rings onto poles prevailed in the species previously linked to advanced physical cognition and tool use. In addition, free object-object combinations were intrinsically structured in Goffin cockatoos and in kea.
... In birds, comparative studies have shown that innovation rate, measured for a large number of species (Lefebvre et al. 1997; Lefebvre 2011), is positively correlated with species introduction success (Sol et al. 2002), habitat generalism (Overington et al. 2011b), urbanization (Liker & Bokony 2009; Sol et al. 2011) and species richness (Nicolakakis et al. 2003; Sol et al. 2005b). At the within-species level, differences among individuals in innovativeness, measured using problem-solving performance, have been well documented in a variety of avian taxa, such as Psittacidae (Funk & Matteson 2004), Falconidae (Biondi et al. 2008), Corvidae (Bluff et al. 2010) and Paridae (Cole et al. 2011), both in captivity (Boogert et al. 2008b; Overington et al. 2011a) and in the field (Gajdon et al. 2006; Keagy et al. 2009; Morand-Ferron et al. * Correspondence: L. Cauchard, Département de Sciences Biologiques, Université de Montréal, Pavillon Marie-Victorin, bureau D-221, C.P. 6128, succ. Centre-ville, Montréal, QC H3C 3J7, Canada. ...
Although interindividual variation in problem-solving ability is well documented, its relation to variation in fitness in the wild remains unclear. We investigated the relationship between performance on a problem-solving task and measures of reproductive success in a wild population of great tits, Parus major. We presented breeding pairs during the nestling provisioning period with a novel string-pulling task requiring the parents to remove an obstacle with their leg that temporarily blocked access to their nestbox. We found that nests where at least one parent solved the task had higher nestling survival until fledging than nests where both parents were nonsolvers. Furthermore, clutch size, hatching success and fledgling number were positively correlated with speed in solving the task. Our study suggests that natural selection may directly act on interindividual variation in problem-solving performance. In light of these results, the mechanisms maintaining between-individual variation in problem-solving performance in natural populations need further investigation. Crown Copyright
... Moreover, the comparative study of infant development and animal cognition might be very useful in gaining information on the nature and evolution of cognition (Gomez 2005), while it is undoubtedly important to keep in mind the possibility that similar abilities in different species may be based on different mechanisms. The presence of object permanence capacity has been extensively studied in many species, including several avian species (Dumas and Wilkie 1995;Etienne 1973;Funk 1996;Funk and Matteson 2004;Pepperberg et al. 1997). Some of these studies (Gomez 2004;Doré and Goulet 1998) have revealed that many species develop object permanence skills in the same sequence as children, only at different speeds. ...
The aim of the present study was to investigate the ontogeny of object permanence in a non-caching corvid species, the jackdaw (Corvus monedula). Jackdaws are often presented as typical examples of non-storing corvids, as they cache either very little or not at all. We used Uzgiris and Hunt's Scale 1 tasks to determine the age at which the certain stages set in and the final stage of this capacity that is reached. Our results show that the lack of food-storing behaviour is not associated with inferior object permanence abilities in the jackdaw, as our subjects (N = 19) have reached stage 5 competence (to follow successive visible displacements) at the average age of 61 days post-hatch and showed some evidence of stage 6 competence (to follow advanced invisible displacements) at 81 days post-hatch and thereafter. As we appreciate that object permanence abilities have a very wide ecological significance, our positive results are probably the consequence of other, more fundamental ecological pressures, such as nest-hole reproduction or prey-predator interactions.
Both the number and breadth of avian cognition studies have expanded in the past three decades. Parrots have a long history as subjects in avian cognition research. This paper summarizes results from a number of parrot species tested on basic learning, and physical & social cognitive processes, with an emphasis on individual differences. Early psittacine studies were aimed at demonstrating a particular cognitive ability existed in a given species. Because of this proof of capacity focus, early studies typically included only a single individual or a dyad of parrots. Existing reviews of parrot cognition tend to focus on a particular cognitive component in a single species, or even a single individual. Despite the narrow focus, results from increasing sample sizes show intraspecific variation across a variety of cognitive assessments and parrot species. Intraspecific variability in performance on cognitive tasks highlights the need for establishing a cognitive normal range for a given species and process. To accomplish this, large numbers of individuals need to be tested and non-cognitive sources of variability need to be controlled. Once species typical cognitive normal ranges are established, cognitive comparisons can be made between parrot species and between parrots and other taxa.
The authors evaluated the ontogenetic performance of a grey parrot (Psittacus erithacus) on object permanence tasks designed for human infants. Testing began when the bird was 8 weeks old, prior to fledging and weaning. Because adult grey parrots understand complex invisible displacements (I. M. Pepperberg & F. A. Kozak, 1986), the authors continued weekly testing until the current subject completed all of I. C. Uzgiris and J. Hunt's (1975) Scale 1 tasks. Stage 6 object permanence with respect to these tasks emerged at 22 weeks, after the bird had fledged but before it was completely weaned. Although the parrot progressed more rapidly overall than other species that have been tested ontogenetically, the subject similarly exhibited a behavioral plateau part way through the study. Additional tests, administered at 8 and 12 months as well as to an adult grey parrot, demonstrated, respectively, that these birds have some representation of a hidden object and understand advanced invisible displacements.
Studied Piagetian causality in a 2.6-yr-old male and a 1.1-yr-old female chimpanzee. Tasks were administered every 6 mo, 3 times for the female and 2 times for the male. Data show that tests of causality are adaptable to chimpanzees. Responses similar to those of human infants were observed. In the female, it was possible to observe a developmental sequence from Stage IV to VI of sensorimotor development of causality. Both Ss reached Stage VI. Attainment of mental representation is discussed. (French abstract) (22 ref)
Psychometric findings are reported from two studies concerning the construct validity, temporal stability, and interrater reliability of the latent common factors underlying subjective assessments by human raters of personality traits in two nonhuman animal species: (a) the Stumptail macaque (Maraca arctoides), a cercopithecine monkey; and (b) the Zebra finch (Poephila guttata), an estrildid songbird. Because most theories of animal personality have historically implied that certain personality constructs should be relatively universal across taxa, parallel analyses of similar data are reported for two phylogenetically distant species of subject using the same psychometric methods. Each of the samples was drawn from a socially-housed colony of the same species: that of macaques consisted of 5 mature adult fem ales and 8 of their adult offspring and that of finches consisted of 5 adult individuals. A modified version of the 1978 Stevenson-Hinde and Zunz (SHZ) list of personality items was applied to the macaques at various times during the eight years from 1980-1988 and to the finches during 1992. This study also used the three SHZ scales - Confident, Excitable, and Sociable - originally derived from principal components. Generalizability analyses were used to assess the construct validity, temporal stability, and interrater reliability of the hypothesized factors. Both Stumptail macaques and Zebra finches manifest measurable personality factors that are highly valid across multiple items, stable across multiple years, and reliable across multiple raters. The same model fits both species, as predicted by theory. The construct validity of the factors is slightly higher for the finches than for the macaques, although the interrater reliability is somewhat lower. This study illustrates how generalizability analysis can be used to test prespecified confirmatory factor models when the number of individual subjects is quite small.
Thirty-six 2-, 4-, and 6-month-old infants were videotaped while interacting with a female adult stranger engaging in either organized or disorganized 1-min peekaboo games. Two-month-old infants gazed and smiled equally at the stranger, regardless of the relative organization of the peekaboo game. In contrast, 4- and 6-month-old infants smiled significantly more and gazed significantly less in the organized peekaboo condition than in the disorganized peekaboo condition. These results suggest that from a diffuse sensitivity to the presence of a social partner, infants by 4 months develop a new sensitivity to the narrative envelope of protoconversation, in particular the timing and the structure of social exchanges scaffolded by adults. These observations are interpreted as evidence of developing social expectations in the first 6 months of life. This early development is viewed as announcing and preparing the communicative competence that blossoms by the end of the 1st year.
During the last 15 years, Piaget's theory and methods have been used to investigate the cognitive capacities and development of nonhuman primates as well as of a few avian and mammalian species. Most studies have focused on formal testing of object permanence, but data are also available on sensory-motor intelligence, on the concepts of space and causality, and on imitation. Some primate studies have tested concrete-operational prerequisites and skills (conservation, classification, and seriation). Methodological flaws and conceptual ambiguities prevent any firm conclusion on the cognitive capacities of some species studied. Reliable data are available on such mammalian carnivores as cats, dogs, and wolves, and various studies confirm the close similarity between ape and human sensory-motor development. There are also indications that great-ape intelligence develops beyond this point, and chimpanzees display basic elements of symbolic representation. The heuristic value and the limits of the Piagetian approach are assessed in terms of its contribution to the analysis of animal cognitive development and to comparative psychology. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Examined the occurrence of individual behavioral differences in wolf cubs and the stability of the differences over the 1st 6 mo of life despite variations in the social environment. A litter of 5 male wolves was tested for reaction to unfamiliar people and unfamiliar objects and in a bone competition situation. The social environment was varied by housing the Ss alternately as a group, in pairs, and in isolation. Although there was a general tendency for less stability to be shown prior to 6 wks of age than after, the behaviors showed high stability over the course of the experiment. Results from the tests with unfamiliar objects indicate less stability when Ss were tested individually than when tested as a group, an effect suggesting that social structure may be a factor that increases the stability of responses to unfamiliar objects. (22 ref) (PsycINFO Database Record (c) 2012 APA, all rights reserved)
The existence of individual differences in behavior is a well-documented but poorly understood phenomenon.....In this chapter, we explicitly pursue the possibility of adaptive and functional individuality. ...We try to develop a framework which relates the appearance and controls on individuality to the life history of an organism and the dynamics of its foraging and social environments. (from the abstract)
Short-term physiological requirements strongly constrain some foragers. During the limited time available for foraging, they must consume sufficient food to meet all energetic expenditures for 24 h. Models for risk-sensitive, decision-making predict that such a forager should be risk-averse toward reward variance when the animal expects to meet its requirement, and should be risk-prone toward reward variance when expecting an energetic deficit. Some previous demonstrations of this shift from risk-averse to risk-prone behaviour relied on differences in both pre-experimental deprivation and inter-trial delays within an experiment to vary the subjects' energy budgets, and these differences have allowed an alternate interpretation of observed preferences. Therefore, earlier work on risk-sensitive foraging in small birds was complemented by manipulating ambient temperature to induce positive and negative expected energy budgets. For a given mean reward, the inter-trial delay was the same, constant length at both temperatures. When subjects experienced a positive energy budget (warm temperature), risk-aversion exceeded preference for risk strikingly; the opposite occurred when the subjects could anticipate a negative energy budget (cold temperature). Variation in inter-trial delays could not have influenced the change in preference reported here.
Behaviour under conditions of mild stress shows consistent patterns in all vertebrates: exploratory behaviour, boldness, aggressiveness covary in the same way. The existence of highly consistent individual variation in these behavioural strategies, also referred to as personalities or coping styles, allows us to measure the behaviour under standardized conditions on birds bred in captivity, link the standardized measurements to the behaviour under natural conditions and measure natural selection in the field. We have bred the great tit (Parus major), a classical model species for the study of behaviour under natural conditions, in captivity. Here, we report a realized heritability of 54 +/- 5% for early exploratory behaviour, based on four generations of bi-directional artificial selection. In addition to this, we measured hand-reared juveniles and their wild-caught parents in the laboratory. The heritability found in the mid-offspring-mid-parent regression was significantly different from zero. We have thus established the presence of considerable amounts of genetic variation for personality types in a wild bird.
This article explores reasons for individual differences in animal behavior and points to various ways in which they deserve closer study. Differences in feeding, mating, or fighting behavior may occur because selection favors the adoption of different strategies by different individuals. Variations in signals may arise through selection for animals to be identifiable as individuals or for their relatedness to others to be assessed. The variability of behavior itself varies between different patterns in which it has been measured. Variation may arise because the exact form of the behavior being measured makes little difference from the point of view of selection. It is also suggested that variability in other cases may come about because, in an unpredictable environment, the best course of action cannot be forecast.
I tested American Robins (Turdus migratorius) for individual differences in fruit consumption and preference when offered six trials of a three-way choice of white mulberry (red variety; Morus alba L.), Bella honeysuckle (Lonicera × bella), and red-osier dogwood (Cornus stolonifera Michx.) fruits. Fruit choice was examined secondarily in relation to indices of fruit quality (fruit mass, percent water, refractive index, trial date, source plant) and in relation to age, sex, and individual morphometric variation of the birds. Pooling all trials and all birds, mulberry was eaten significantly more than either honeysuckle or dogwood. Although adults differed from juveniles in body mass at capture and in relative bill dimensions, fruit choice did not vary in relation to age or sex. Also, juveniles were not more variable than adults in fruit choice. However, individual birds differed significantly in fruit choice (15 preferred mulberry, 2 preferred dogwood, 0 preferred honeysuckle), and 15 individuals were consistent in fruit choice from trial-to-trial. Indices of fruit quality changed over the course of the study. For each of the three fruit species, some variables were significantly different among individual plants, over time, or both. Some fruit-quality variables explained small but significant amounts of variation in fruit consumption (numbers of fruits eaten) and preference (number of fruit A eaten/[(number of fruit B eaten) + (number of fruit C eaten)]. Robins preferred fruits from mulberry trees that had fruits of relatively lower mass and higher refractive index. After I controlled for effects of fruit quality, trial date, and source plant in multiple regression analyses, residual consumption and preference scores still differed significantly among individuals. Residuals for mulberry and dogwood were negatively correlated, which implies a trade-off in consumption of these two fruits. Individual differences in body mass, but not in bill or wing dimensions, explained significant amounts of the variation in residual mulberry consumption and in mulberry and dogwood preference. Heavier robins tended to prefer and eat more mulberries, the largest fruit, whereas lighter robins preferred dogwood fruits, which were the smallest. Dietary diversity correlated positively with wing length.
Does human cognitive development advance through a series of broad and general stages? If so, the child's mind at any point in its development should seem quite consistent and similar across situations in its maturity level and general style. That is, it should be relatively "homogeneous" rather than "heterogeneous" at any given age. There appear to be factors and considerations that make for both heterogeneity and homogeneity in the child's cognitive life. As to heterogeneity, many cognitive items (concepts, skills, etc.) may develop independently; they may not assist each other's development and there may be no common mediator to assist their codevelopment. Likewise, mental heterogeneity may occur because human beings have evolved to cope with certain cognitive tasks earlier or more easily than others. Intraindividual differences in aptitudes and experiences could also produce considerable heterogeneity. As to homogeneity, the child's information-processing capacity may impose an upper limit on how heterogeneous her mental level could be. There may also be more cognitive homogeneity (1) in the child's initial reaction to inputs than in her subsequent management of them; (2) at the beginning and end of an acquisitional sequence than in the middle of it; (3) in spontaneous, everyday cognition than in formal task or test situations; (4) in some cognitive domains than in others; (5) in some children than in others. It was concluded that cognitive development might appear more general-stage-like than many of us believed, if only we knew how and where to look.
Developmental and child psychology remains a vital area in modern psychology. This comprehensive set covers a broad spectrum of developmenal issues, from the psychology of the infant, the family, abilities and disabilities, children's art, imagination, play, speech, mental development, perception, intelligence, mental health and education. In looking at areas which continue to be very important today, these volumes provide a fascinating look at how approaches and attitudes to children have changed over the years. The set includes nine volumes by key development psychologist Jean Piaget, as well as titles by Charlotte Buhler and Susan Isaacs.
Individual recognition of nestling distress screams by European starlings (Sturnus vulgaris) was assessed by comparing the responses of free-living parents to playbacks of screams recorded from their own young or from neighbouring chicks. Individual variation in the acoustic structure of distress screams was analysed to assess whether they were likely to afford an acoustic basis for individual recognition. Parents hearing screams of their own young were significantly more likely to make diving attacks on the speaker than parents hearing the screams of neighbouring chicks. Thus nestling screams appear to function as individually indentifiable calls for aid. Multivariate analysis of variance employing 9 acoustic parameters of nestling screams revealed significant differences among groups of screams recorded from different chicks, suggesting that screams could afford a suitable basis for individual recognition. Post-hoc F-tests suggest that the period and extent of rapid frequently modulations would provide the best cues to the identity of the caller.
Dove coos are known to be important for intra-specific communication in various contexts. Earlier research showed the occurrence of systematic frequency modulations for the perch- coo of the collared dove and suggested that presence or absence of these modulations might be important in communication. The present study examined the occurrence of frequency modulations and frequency use for perch-, bow- and nest-coo, as well as variation in these features between and within individuals, to assess the acoustic ‘signal space’ for this species. The occurrence of frequency modulations was high for perch- and bow-coo, but low for the nest-coo. The relative distribution of modulations over the three elements of a coo differed for the various coo types. Coo types differed also in their ‘frequency profiles’. Frequency use is correlated with the occurrence of modulations. Differences between coo- types as well as variation within a coo-type and within individuals can be described by a limited set of parameters, which may be linked to basic properties of the coo producing mechanism. As a consequence of the occurrence of modulations and their distribution over the coo-types, the acoustic differences between the coo-types are amplified. As the different coo-types serve different functions, presence of modulations increases the signal space and decreases the ambiguity of the coo types. Differences between individuals exceeded those within individuals and were largest for perch- and bow-coo, which both serve in territorial defence and mate attraction.
Individual differences in response to a number of animate and inanimate moving and non-moving stimuli were studied in 18 wolf cubs from four litters. Social rank was closely correlated with reactivity, exploratory behavior and prey-killing ability. A wide range of variability in test scores was found in all litters. It is proposed that pack integration and coordination of activities is enhanced by intra-specific socialization, social facilitation, and leader-follower relationships between subordinates and the more exploratory alpha individual. The evolutionary advantages of selection for individual differences or behavioral polymorphism within litters are discussed and inferences drawn for significance in pack formation. This hypothesis is supported by contrasting evidence of greater behavioral homogeneity in less social canids, where intra-specific aggression and mutual proximity intolerance prevents pack formation and leads to dispersal of the litter.
Assessment of the similarity of sound spectrograms of the loud advertising vocalizations of bitterns (booms) by observers using subjective, qualitative criteria shows that the booms of bitterns are individually distinctive. Multivariate quantitative measures also showed booms to be individually distinctive. Both qualitative and quantitative assessments showed that booms from the same individual are consistent within and between years. The usefulness of individual distinctiveness in vocalizations for collecting data on within and between year survival is discussed, as are the factors limiting the technique.
The response of six groups of captive, handreared jackdaws, Corvus monedula L. (Aves), to a novel space was tested. Birds were tested in groups and were free to make contact with the novelty or remain in a familiar area. The individual manner of response was related to the social position of the individual. i) Exploratory behaviour occurred in bouts. Familiarization with the novelty was mostly gradual, but in some groups after an initial delay, the entire group began to explore and then to enter the novel space very rapidly (
Eleven young golden-crowned parakeets (Cyanoramphus auriceps) were assessed on 11 Piagetian activities that have been used to examine sensory and motor spatial development in human infants and nonhuman primates. Examples of these early abilities are: grasping, localizing sounds, following trajectories of objects, investigating objects, repeatedly dropping them, filling and emptying containers, and making detours. Human infants perform these activities spontaneously in their first 2 years. The tasks were presented to the young birds to investigate their natural abilities; there was no attempt to teach them to do those tasks that they did not spontaneously perform. The birds completed 9.5 of the 11 tasks, failing in general to combine objects. Their ordinality on the tasks differed from that of human infants. The two groups of birds tested performed the middle level tasks in a mixed order, possibly because these altricial birds need many of these basic abilities soon after fledging and so these particular skills may not emerge in any set order for the birds.
Studied the relation of strength of stimulus, to rapidity of learning in 18 kittens. The kittens had to discriminate between the light-dark boxes. The experiment box was divided into a nest box, an entrance chamber and 2 electric boxes. The electric boxes were placed in the circuit of a constant electric current. The kittens received electric shock in these boxes. The results indicate that: (1) it took less number of trials to perfect a correct habit with a strong stimulus than with a medium stimulus, under conditions of learning of varying difficulty (2) the relation of the painfulness of the electric stimulus to the rapidity of habit formation depended upon the difficulty of the visual discrimination, and (3) the discrimination was difficult to make when the difference between the unpleasant and the very unpleasant stimuli was not marked. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Describes the theoretical background, development, and use of a novel approach to the assessment of psychological development in infancy. 7 scales developed for assessing separately an infant's progress in various areas of intellectual functioning (e.g., visual pursuit and permanence of objects, gestural imitation, and vocal imitation) are outlined, and the value of viewing an infant's achievements as a coherent sequence of ordered levels is examined. (8 p ref) (PsycINFO Database Record (c) 2012 APA, all rights reserved)
This volume brings together two kinds of material: a discussion of theoretical issues that arise in relation to assessment of early development from a Piagetian perspective and a presentation of experience resulting from attempts to foster psychological development founded on such assessments.
The Introduction to this volume presents the background leading up to the construction of these ordinal Scales as well as an overview in greater detail of the individual chapters. The volume as a whole provides a summary and an evaluation of research that has been done using the Scales. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
The target authors make a strong case for parallels between human and nonhuman metacognition. The case may be bolstered by an appeal to the literatures on commitment and self-control and to that on observing behavior.
Oystercatchers have two methods of opening mussels, both neatly adapted to the structure of the prey. To open mussels exposed by the tide, the bird hammers a hole along the ventral margin of the shell, whereas to open mussels under water, the bird drives its bill into the gape of the valves to cut through the posterior adductor muscle. Large and strong-shelled mussels can be opened by stabbing but not by hammering.
Feeding methods of Oystercatchers vary from mussel-bed to mussel-bed. These variations in behaviour are attributable to differences in the strength of the shells of the prey and to the firmness of their attachment to the substrate.
Diversity of ecological conditions on the mussel-beds causes an apparent size selection of prey by Oystercatchera.
This study investigated the role of dominance and level of activity and exploration on leadership in zebra nches (Taenopygia guttata) searching for food. In pairs of zebra nches fairly matched in size and that experienced the same level of food deprivation, the same bird consistently reached rst one foraging patch over several trials. The same pattern of arrival to food occurred when resources were provided in two distant patches available concurrently, a situation that would potentially allow subordinates a greater access to resources. In further testing, the formation of new pairs with the same birds led to several changes in leadership, indicating that leadership is not an absolute feature. The member of a pair that proved to be the most active and exploratory during independent, solitary trials became the leader in nearly all pairs tested. The same pattern held true in newly rearranged pairs where individuals often experienced changes in dominance status. Dominance failed to be associated with leadership in all tests. The results suggest that in a relatively egalitarian species, level of activity and exploration may be a stronger predictor of leadership than dominance.
Eleven young kakarikis (Cyanoramphus auriceps) were tested on 15 object-permanence tasks in a standardized scale that has been used to assess the development of human
infants, some nonhuman primates, and other mammals. The birds successfully completed all tasks in this scale, and many aspects
of their testing were similar to human results, such as evidencing the A-not-B error. However, the birds differed slightly
but significantly from human subjects in that some of the “invisible displacements” of the later tasks were performed before
the earlier visible displacement tasks. These results may relate to common ecological activities of this species. Six of the
birds were parent-raised; 5 were hand-raised. The hand-raised birds achieved criteria more quickly than did the parent-raised
birds possibly because the former were more accustomed to the investigator and less distractible in the test situation.
Four psittacids—an African Grey parrot, an Illiger macaw, a cockatiel, and a parakeet—were tested on object-permanence tasks
that are commonly used to assess levels of understanding in human infants during their first 2 years. These birds showed Stage
6 competence, demonstrating that object permanence is not limited to mammals. The results for these birds were comparable
to those of an African Grey parrot that had been trained in interspecies communication prior to object-permanence testing.
Our findings thus suggest that although language-like behavior provides a communication channel that facilitates testing,
such language training is unlikely to affect the outcome of the tests.
Individual differences in early exploratory behaviour were investigated in hand-reared juvenile male great tits, Parus major, during the first 18 weeks of their life. The juveniles differed consistently in their reaction to a novel object in a familiar environment, either when tested with different objects or when tested again after 9 weeks. Birds that approached a novel object more quickly were also quicker to visit all artificial trees present in a novel environment than birds that approached a novel object more slowly. These behavioural differences extended to the strength of foraging habits, built up during a training period in which food was always offered at the same place. After a change in the location of food, the quicker birds would keep going to the place where the food used to be. The slower birds tended to change their behaviour and stop going to the former place. The results show that juvenile male great tits differ consistently in various aspects of their exploratory behaviour at least during the first 18 weeks of life. The variation in behaviour was not likely to arise from differences in general activity or physical condition, but seems to refer to differences in the way in which information concerning the environment is collected and dealt with.
Primate Cognition What can we learn from ape behaviour experiments about consciousness? Are apes a model for humans - are they conscious at our level at all? Not finally answered here but a good overview.
The authors evaluated the ontogenetic performance of a grey parrot (Psittacus erithacus) on object permanence tasks designed for human infants. Testing began when the bird was 8 weeks old, prior to fledging and weaning. Because adult grey parrots understand complex invisible displacements (I. M. Pepperberg & F. A. Kozak, 1986), the authors continued weekly testing until the current subject completed all of I. C. Uzgiris and J. Hunt's (1975) Scale 1 tasks. Stage 6 object permanence with respect to these tasks emerged at 22 weeks, after the bird had fledged but before it was completely weaned. Although the parrot progressed more rapidly overall than other species that have been tested ontogenetically, the subject similarly exhibited a behavioral plateau part way through the study. Additional tests, administered at 8 and 12 months as well as to an adult grey parrot, demonstrated, respectively, that these birds have some representation of a hidden object and understand advanced invisible displacements.
Despite the long divergent evolutionary history of birds and mammals, early avian and primate cognitive development have many convergent features. Some of these features were investigated with a series of tasks designed to assess human infant development. The tasks were presented to young parakeets to assess their means-end problem solving abilities. Examples of these early skills are: attaining and playing with objects, retrieving rewards through use of a stick or rake, or by pulling in rewards on supports or on the ends of strings. Twelve such tasks were presented to 11 young yellow-crowned parakeets ( Cyanoramphus auriceps) to investigate their natural abilities; there was no attempt to train them to do those tasks that they did not spontaneously perform. Six of the birds were parent-raised and five were hand-raised. The birds completed 9 of the 12 tasks, demonstrating all the Piagetian sensorimotor circular reactions, but they failed to hand-watch ("claw-watch"), to stack objects, or to fill a container. Their ordinality on the tasks differed from that of human infants in that locomotion to obtain objects occurred earlier in the avian sequence of development and the mid-level tasks were performed by the two groups of avian subjects in a mixed order perhaps indicating that these abilities may not emerge in any particular order for these birds as they supposedly do for human infants. The hand-raised group needed fewer sessions to complete these means-end tasks.
Behavioural ecology of the red-crowned parakeet and yellow-crowned parakeet on Little Barrier Island. Unpublished master’s thesis
- T Greene
- T. Greene
Greene, T. (1988). Behavioural ecology of the red-crowned parakeet
and yellow-crowned parakeet on Little Barrier Island. Unpublished
master's thesis, University of Auckland, New Zealand.
Status, habits and conservation of Cyanoramphus parakeets in the New Zealand regionConservation of island birds: Case studies for the management of threatened island species
- R Taylor