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Articles 31 - 60 of 84
Full-Text Articles in Behavior and Ethology
‘Neuroecologists’ Are Not Made Of Straw, Robert R. Hampton, Susan D. Healy, Sara J. Shettleworth, Alan Kamil
‘Neuroecologists’ Are Not Made Of Straw, Robert R. Hampton, Susan D. Healy, Sara J. Shettleworth, Alan Kamil
Papers in Behavior in Biological Sciences
In the October issue of Trends in Cognitive Sciences, Bolhuis and Macphail criticized the functional/evolutionary approach to the neural mechanisms of learning and memory, and concluded that the approach is ‘often misleading and might provide us with the wrong answers’ [1]. Their critique touches on a number of interesting issues, and provides a useful prompt to examine the role of an adaptationist approach to the study of cognition. In their effort to stimulate discussion, however, Bolhuis and Macphail have overstated positions they attribute to ‘neuroecologists’.
Spatial And Social Cognition In Corvids: An Evolutionary Approach, Russell P. Balda, Alan Kamil
Spatial And Social Cognition In Corvids: An Evolutionary Approach, Russell P. Balda, Alan Kamil
Papers in Behavior in Biological Sciences
The central research questions that have guided our studies since 1981 combine issues and techniques from both comparative psychology and avian ecology. Most of our questions originate from the cognitive implications of extensive field studies on the natural history, ecology, and behavior of seed-caching corvids. Because our questions have evolved as our studies progressed, we have chosen to give a historical perspective outlining the progression of our ideas and questions.
The Use Of Landmarks By Clark's Nutcrackers: First Tests Of A New Model, Alan Kamil, Aleida J. Goodyear, Ken Cheng
The Use Of Landmarks By Clark's Nutcrackers: First Tests Of A New Model, Alan Kamil, Aleida J. Goodyear, Ken Cheng
Papers in Behavior in Biological Sciences
Animals use many different mechanisms to navigate in space. The characteristics of the mechanism employed are usually well-suited to the demands of each particular navigational problem. For example, desert ants navigating in a relatively featureless environment use path integration, birds homing or migrating over long distances use compasses of various sorts, salmon returning to their natal stream home on olfactory cues. The study of navigation requires the study of many different taxa confronting different problems. One interesting case 1 involves scatter-hoarding species that use memory to relocate their hidden food. Such animals face the problem of remembering many locations simultaneously. …
Limited Attention: The Constraint Underlying Search Image, Reuven Dukas, Alan Kamil
Limited Attention: The Constraint Underlying Search Image, Reuven Dukas, Alan Kamil
Papers in Behavior in Biological Sciences
Recent models of predator search behavior integrate proximate neurobiological constraints with ultimate economic considerations. These models are based on two assumptions, which we have critically examined in experiments with blue jays searching for artificial prey images presented on a computer monitor. We found, first, that when jays had to switch between searching for two distinct prey types, they showed no reduction in detection rates compared to no-switching to no-switching conditions, and second, that when jays divided attention between searching for two prey types at the same time, they had lower detection rates than when they focused attention on one prey …
Tests For Cognitive Mapping In Clark’S Nutcrackers (Nucifraga Columbiana), Brett M. Gibson, Alan Kamil
Tests For Cognitive Mapping In Clark’S Nutcrackers (Nucifraga Columbiana), Brett M. Gibson, Alan Kamil
Papers in Behavior in Biological Sciences
In these experiments, the authors examined the nature of the spatial information that Clark’s nutcrackers (Nucifraga columbiana) use during navigation and whether this information is represented in the form of a cognitive map. In Experiment 1, nutcrackers were able to use distal cues to locate a small hidden goal. In Experiments 2 and 3, nutcrackers were given the opportunity to develop a map of a room by viewing local subsets of the landmarks in the room at a goal during training. During transfer tests, nutcrackers were presented with a landmark panorama that was not previously seen at the …
Search For A Hidden Goal By Clark's Nutcrackers (Nucifraga Columbiana) Is More Accurate Inside Than Outside A Landmark Array, Brett M. Gibson, Alan C. Kamil
Search For A Hidden Goal By Clark's Nutcrackers (Nucifraga Columbiana) Is More Accurate Inside Than Outside A Landmark Array, Brett M. Gibson, Alan C. Kamil
Papers in Behavior in Biological Sciences
In three experiments in which an open-room delayed response task was used, we explored how Clark's nutcrackers use landmarks to search for a hidden goal when multiple potential goal locations were present. In Experiment 1, nutcrackers presented with three spatial samples were able to use relative local cues from an array that changed positions throughout a session to return to a hidden goal during a test. In Experiment 2, the number of samples varied from one to three prior to the test. The nutcrackers performed as well with one sample as with two or three samples. In Experiment 3, we …
The Use Of Relative And Absolute Bearings By Clark's Nutcrackers, Nucifraga Columbiana, Juli E. Jones, Alan C. Kamil
The Use Of Relative And Absolute Bearings By Clark's Nutcrackers, Nucifraga Columbiana, Juli E. Jones, Alan C. Kamil
Papers in Behavior in Biological Sciences
Two groups of Clark's nutcrackers were trained to find buried seeds whose location was defined by a constant angle from two landmarks whose interlandmark distance and position in the room varied across trials. The first group had a landmark array that was always placed in the same orientation with respect to the walls, allowing the animals to use both relative and absolute bearings. The second group had a landmark array that rotated across trials so that only relative bearings could be used to locate the seeds. The birds in each group learned the task and transferred to new interlandmark distances …
Way-Finding And Landmarks: The Multiple Bearings Hypothesis, Alan C. Kamil, Ken Cheng
Way-Finding And Landmarks: The Multiple Bearings Hypothesis, Alan C. Kamil, Ken Cheng
Papers in Behavior in Biological Sciences
Clark’s nutcrackers (Nucifraga columbiana) are capable of very precise searching using the metric relationships between a goal and multiple landmarks to relocate the goal location. They can judge the direction more accurately than the distance to a landmark when the landmark is distant from the goal. On the basis of these findings, we propose that nutcrackers use a set of bearings, each a measure of the direction from the goal to a different landmark, when searching for that goal. The results of a simulation demonstrate that increasing the number of landmarks used results in increasingly precise searching. This …
Review Of Evolution And Cognition, Edited By Cecilia Heyes And Ludwig Huber., Alan Kamil
Review Of Evolution And Cognition, Edited By Cecilia Heyes And Ludwig Huber., Alan Kamil
Papers in Behavior in Biological Sciences
Heyes and Huber have edited a volume that surveys much of the current research into cognition in animals, reflecting the strengths and weaknesses of this field. The book is divided into five sections. In the first part, titled “Orientations,” four authors lay out their basic general views of the field. The first two chapters in this section are by the editors. First, Heyes makes the case for an approach to evolutionary psychology that she labels “in the round,” an approach that would encompass studies of human and nonhuman animals alike and include a broad range of contemporary evolutionary approaches. This …
Geometric Rule Learning By Clark’S Nutcrackers (Nucifraga Columbiana), Alan Kamil, Juli E. Jones
Geometric Rule Learning By Clark’S Nutcrackers (Nucifraga Columbiana), Alan Kamil, Juli E. Jones
Papers in Behavior in Biological Sciences
Clark’s nutcrackers (Nucifraga columbiana) were trained to search in a location defined by its geometric relationship to 2 landmarks. Two groups were trained to search at different points along the line connecting the landmarks, and 2 groups were trained to find the 3rd point of a triangle, on the basis of either direction or distance from the landmarks. All groups learned and transferred to new interlandmark distances. However, the constant-distance group learned more slowly, searched less accurately, and showed less transfer than the other 3 groups. When tested with new orientations of the landmarks, the birds tended to …
The Cost Of Limited Attention In Blue Jays, Reuven Dukas, Alan Kamil
The Cost Of Limited Attention In Blue Jays, Reuven Dukas, Alan Kamil
Papers in Behavior in Biological Sciences
Experiments with fish and birds suggest that animals are unable to simultaneously allocate sufficient attention to tasks such as the detection of an approaching predator while searching for cryptic prey. We quantified the effects of limited attention on performance in controlled laboratory settings and report here the first direct evidence that attending to a difficult central task simulating foraging deters a bird’s ability to detect a peripheral target, which could be a predator. Our results fill a gap between ecological and neurobiological studies by illustrating that, although attention is an efficient filtering mechanism, limited attention may be a major cause …
Searching Image In Blue Jays: Facilitation And Interference In Sequential Priming, Alan B. Bond, Alan C. Kamil
Searching Image In Blue Jays: Facilitation And Interference In Sequential Priming, Alan B. Bond, Alan C. Kamil
Papers in Behavior in Biological Sciences
Repeated exposure to a single target type (sequential priming) during visual search for multiple cryptic targets commonly improves performance on subsequent presentations of that target. It appears to be an attentional phenomenon, a component of the searching image effect. It has been argued, however, that if searching image is an attentional process, sequential priming should also interfere with performance on subsequent nonprimed targets, and such interference has never been unequivocally demonstrated. In blue jays (Cyanocitta cristata) searching in an operant apparatus for targets derived from images of cryptic moths, detection performance was strongly facilitated in the course of …
Sociality And Social Learning In Two Species Of Corvids: The Pinyon Jay (Gymnorhinus Cyanocephalus) And The Clark’S Nutcracker (Nucifraga Columbiana), Jennifer J. Templeton, Alan Kamil, Russell P. Balda
Sociality And Social Learning In Two Species Of Corvids: The Pinyon Jay (Gymnorhinus Cyanocephalus) And The Clark’S Nutcracker (Nucifraga Columbiana), Jennifer J. Templeton, Alan Kamil, Russell P. Balda
Papers in Behavior in Biological Sciences
The hypothesis that social learning is an adaptive specialization for social living predicts that social species should learn better socially than they do individually, but that nonsocial species should not exhibit a similar enhancement of performance under social learning conditions. The authors compared individual and social learning abilities in 2 corvid species: the highly social pinyon jay (Gymnorhinus cyanocephalus) and the less social Clark’s nutcracker (Nucifraga columbiana). The birds were tested on 2 different tasks under individual and social learning conditions. Half learned a motor task individually and a discrimination task socially; the other half learned …
A Method For Estimating Marine Habitat Values Based On Fish Guilds, With Comparisons Between Sites In The Southern California Bight, Alan B. Bond, John S. Stephens, Jr., Daniel J. Pondella, Ii, M. James Allen, Mark Helvey
A Method For Estimating Marine Habitat Values Based On Fish Guilds, With Comparisons Between Sites In The Southern California Bight, Alan B. Bond, John S. Stephens, Jr., Daniel J. Pondella, Ii, M. James Allen, Mark Helvey
Papers in Behavior in Biological Sciences
Habitat valuation is an essential tool for tracking changes in habitat quality and in adjudicating environmental mitigation. All current methods for estimating habitat values of coastal marine sites rely heavily on the opinion of experts or on data variables that can readily be manipulated to influence the outcome. As a result, unbiased, quantitative comparisons between the values of different marine habitats are generally unavailable. We report here on a robust, objective technique for the valuation of marine habitats that makes use of data that are commonly gathered in surveys of marine fish populations: density, fidelity, and mean size. To insure …
Apostatic Selection By Blue Jays Produces Balanced Polymorphism In Virtual Prey, Alan B. Bond, Alan Kamil
Apostatic Selection By Blue Jays Produces Balanced Polymorphism In Virtual Prey, Alan B. Bond, Alan Kamil
Papers in Behavior in Biological Sciences
Apostatic selection, in which predators overlook rare prey types while consuming an excess of abundant ones, has been assumed to contribute to the maintenance of prey polymorphisms. Such an effect requires predators to respond to changes in the relative abundance of prey, switching to alternatives when a focal prey type becomes less common. Apostatic selection has often been investigated using fixed relative proportions of prey, but its effects on predator–prey dynamics have been difficult to demonstrate. Here we report results from a new technique that incorporates computer-generated displays into an established experimental system, that of blue jays (Cyanocitta cristata …
The Ecology And Evolution Of Spatial Memory In Corvids Of The Southwestern Usa: The Perplexing Pinyon Jay, Russell P. Balda, Alan Kamil
The Ecology And Evolution Of Spatial Memory In Corvids Of The Southwestern Usa: The Perplexing Pinyon Jay, Russell P. Balda, Alan Kamil
Papers in Behavior in Biological Sciences
The corvids of the southwest possess many adaptations for the harvest, transport, caching and recovery of pine seeds. However, there is a large degree of between-species variation in the distribution of these traits. These corvids have a well-accepted phylogeny (Hope, 1989), live within close proximity to one another and have relatively well-known natural histories. They therefore present an excellent opportunity to apply the comparative method (Kamil, 1988) to the study of these species differences (Balda et al., 1997). The comparative method for the study of adaptation and evolution of behavioral traits begins with a careful study of the natural histories …
On The Proper Definition Of Cognitive Ethology, Alan Kamil
On The Proper Definition Of Cognitive Ethology, Alan Kamil
Papers in Behavior in Biological Sciences
The last 20-30 years have seen two “scientific revolutions” in the study of animal behavior: the cognitive revolution that originated in psychology, and the Darwinian, behavioral ecology revolution that originated in biology. Among psychologists, the cognitive revolution has had enormous impact. Similarly, among biologists, the Darwinian revolution has had enormous impact. The major theme of this chapter is that these two scientific research programs need to be combined into a single approach, simultaneously cognitive and Darwinian, and that this single approach is most appropriately called cognitive ethology.
Preface: Animal Cognition In Nature, Russell P. Balda, Irene M. Pepperberg, Alan Kamil
Preface: Animal Cognition In Nature, Russell P. Balda, Irene M. Pepperberg, Alan Kamil
Papers in Behavior in Biological Sciences
This volume, Animal Cognition in Nature, is the result of an ongoing synthesis of several ideas that were considered revolutionary, if not heretical, in the 1960s. At that time, animal behavior, whether studied in field or laboratory, by ethologists or psychologists, was generally interpreted as the result of simple processes relating specific stimuli to specific behaviors. Examples from that time include S–R models, sign stimuli, IRMs, etc. Theoretical constructs such as mental representations, memory or attention were avoided. Today, students of animal behavior work in an entirely different atmosphere. This is the result of several developments.
One of these developments …
Exercise Capacity Of House Wren Nestlings: Chicks Are Not Working As Hard As They Can, Mark A. Chappell, Gwendolyn C. Bachman
Exercise Capacity Of House Wren Nestlings: Chicks Are Not Working As Hard As They Can, Mark A. Chappell, Gwendolyn C. Bachman
Papers in Behavior in Biological Sciences
We measured the aerobic capacity for exercise in house wren (Troglodytes aedon) nestlings from 3 to 10 days of age. Exercise data were compared with previous measurements of the energy cost of begging (Ebeg) to determine if begging chicks are working at maximal exercise capacity. We also compared exercise with the peak metabolic rate during digestion and, in older chicks, with thermogenic heat production. Rates of oxygen consumption (VO2) during exercise increased rapidly with age, but the factorial aerobic scope for exercise (exercise VO2/resting VO2) averaged only 1.4 (at three …
The Effect Of Background Cuing On Prey Detection, Henry Kono, Pamela J. Reid, Alan Kamil
The Effect Of Background Cuing On Prey Detection, Henry Kono, Pamela J. Reid, Alan Kamil
Papers in Behavior in Biological Sciences
Studies of prey detection have typically focused on how search image affects the capture of cryptic items. This study also considers how background vegetation influences cryptic prey detection. Blue jays, Cyanocitta cristata, searched digitized images for two Catocala moths: C. ilia, which is cryptic on oak, and C. relicta, which is cryptic on birch. Some images contained moths while others did not. The ability of blue jays to detect prey during repeated presentations of one prey type within a session was compared with their performance during randomly alternating presentations of both prey types within a session to …
Visual Search For Natural Grains In Pigeons (Columba Livia) : Search Images And Selective Attention, Cynthia M. Langley, Donald A. Riley, Alan B. Bond, Namni Goel
Visual Search For Natural Grains In Pigeons (Columba Livia) : Search Images And Selective Attention, Cynthia M. Langley, Donald A. Riley, Alan B. Bond, Namni Goel
Papers in Behavior in Biological Sciences
The experiments reported here were designed to test the suggestion of many researchers that selective attention to visual features of a prey can account for search-image effects. In 3 experiments pigeons ate wheat and vetch grains presented on multicolored and gray gravel trays. In Experiment 1 search-image effects were evident when grains were cryptic but not when they were conspicuous. Experiment 2 demonstrated that search images can be activated when the grains encountered are either cryptic or conspicuous but that search images affect search performance only when the grains are cryptic. Experiment 3 demonstrated that search images are short-term in …
Predicting Cognitive Capacity From Natural History: Examples From Four Species Of Corvids, Russell P. Balda, Alan Kamil, Peter A. Bednekoff
Predicting Cognitive Capacity From Natural History: Examples From Four Species Of Corvids, Russell P. Balda, Alan Kamil, Peter A. Bednekoff
Papers in Behavior in Biological Sciences
Birds have been studied for centuries because they are numerous, conspicuous, and aesthetically pleasing to humans. Despite their overall regard for birds, historically, many ornithologists have considered birds as instinct-driven organisms of little intellectual capacity. For example, the ornithological textbook of choice from the 1960s states the following view of avian intelligence:
Flight has proven to be an enormously successful evolutionary venture, but one that has cost birds dearly in mental development. In effect, problems merely by flying away from them. … As a consequence, much [avian] behavior is, by mammalian standards, fragmentary, stereotyped, and at times amazingly stupid. (Welty, …
Performance Of Four Seed-Caching Corvid Species In Operant Tests Of Nonspatial And Spatial Memory, Deborah J. Olsen, Alan Kamil, Russell P. Balda, Pamela J. Nims
Performance Of Four Seed-Caching Corvid Species In Operant Tests Of Nonspatial And Spatial Memory, Deborah J. Olsen, Alan Kamil, Russell P. Balda, Pamela J. Nims
Papers in Behavior in Biological Sciences
The performance of 4 seed-caching corvid species was tested using 2 different operant nonmatching tasks. These species differ in their dependence on stored food, and differences in spatial memory tests have been correlated with better performance by the more cache-dependent species. Acquisition and retention of a color non-matching-to-sample task was tested in Experiment 1. Acquisition of the color task was not correlated with cache dependence, and no differences between species in performance during memory testing were found. Acquisition and retention of an operant spatial non-matching-to-sample task was tested in Experiment 2. Species differences in the spatial task were found for …
The Effects Of Requiring Different Response Strategies Following Caching In Clark’S Nutcrackers (Nucifraga Columbiana), Alan Kamil, Russell P. Balda, Deborah J. Olson
The Effects Of Requiring Different Response Strategies Following Caching In Clark’S Nutcrackers (Nucifraga Columbiana), Alan Kamil, Russell P. Balda, Deborah J. Olson
Papers in Behavior in Biological Sciences
Clark’s nutcrackers use spatial memory to recover stored food in the field and have performed very well in laboratory tests of spatial memory. During the present experiment, two groups of nutcrackers cached seeds every 4 days. Following each cache session, the stay group was tested with seeds in their caches; the shift group found seeds in novel sites. The stay group performed accurately throughout the experiment, but the shift group gave no indication of being able to learn to avoid sites where they had stored seeds. These results suggest that although nutcrackers can learn to shift away from remembered locations …
Performance Of Four Seed-Caching Corvid Species In The Radial-Arm Maze Analog, Alan Kamil, Russell P. Balda, Deborah J. Olson
Performance Of Four Seed-Caching Corvid Species In The Radial-Arm Maze Analog, Alan Kamil, Russell P. Balda, Deborah J. Olson
Papers in Behavior in Biological Sciences
Four seed-caching corvid species were tested in an open-room analog of the radial-arm maze. During Experiment 1, the species more dependent on stored food, Clark’s nutcrackers (Nucifraga columbiana) and pinyon jays (Gymnorhinus cyanocephalus), acquired the task more quickly and to higher accuracy levels than either scrub jays (Aphelocoma coerulescens) or Mexican jays (A. ultramarina). During Experiment 2, performance after retention intervals was tested. When intervals of 30-210 min were tested in ascending order, species differences observed during acquisition were again obtained. However, when intervals of 5-300 min were tested in random order, …
Effects Of Response Strategy And Retention Interval On Performance Of Clark’S Nutcrackers In A Radial Maze Analogue, Deborah J. Olson, Alan C. Kamil, Russell P. Balda
Effects Of Response Strategy And Retention Interval On Performance Of Clark’S Nutcrackers In A Radial Maze Analogue, Deborah J. Olson, Alan C. Kamil, Russell P. Balda
Papers in Behavior in Biological Sciences
Two groups of Clark’s nutcrackers (Nucifraga columbiana) were trained to use either a stay or shift response strategy in a radial maze analogue. Each trial had a preretention stage, a retention interval, and a postretention test. In Experiment 1, acquisition with a 5-min retention interval was studied. Response strategy did not affect the rate at which the task was learned. Performance following longer retention intervals was tested in Experiments 2-4. Changes in retention intervals were presented in trial blocks of increasing duration in Experiment 2 and were randomly presented between trials in Experiment 3. Experiment 4 extended the …
Population Estimates Of Kea In Arthur's Pass National Park, Alan B. Bond, Judy Diamond
Population Estimates Of Kea In Arthur's Pass National Park, Alan B. Bond, Judy Diamond
Papers in Behavior in Biological Sciences
The population dynamics of a local group of Kea (Nestor notabilis) was studied at a refuse dump in Arthur's Pass National Park over the course of three successive summers. The mean number of buds that foraged at the dump during the summer was estimated as 20 juveniles, 10 subadults, and 36 adults. An average of 11% of these birds were females. The number of adults was quite stable across years. The total population of Kea in this area was estimated to be between 88 and 119, or in the order of 0.018 to 0.040 buds per hectare. Mortality …
Aggressive Motivation In The Midas Cichlid: Evidence For Behavioral Efference, Alan B. Bond
Aggressive Motivation In The Midas Cichlid: Evidence For Behavioral Efference, Alan B. Bond
Papers in Behavior in Biological Sciences
Behavioral Efference is a hypothetical positive feedback from the performance of an aggressive display that augments the level of aggressive motivation. The hypothesis was proposed (Bond, 1989) to account for the occurrence of truthful communication during aggressive encounters, even in the face of a presumed selective pressure in favor of deceit (Maynard Smith, 1984). Evidence of Behavioral Efference was sought in an experimental study of adult Midas cichlids Cichlasoma citrinellum, in which subjects responded aggressively to varying sizes of dummy fish. Before and after each aggression trial, the level of aggressive motivation was estimated from the intensity of the subject’s …
Searching Image In The Pigeon: A Test Of Three Hypothetical Mechanisms, Alan B. Bond, Donald A. Riley
Searching Image In The Pigeon: A Test Of Three Hypothetical Mechanisms, Alan B. Bond, Donald A. Riley
Papers in Behavior in Biological Sciences
The searching image hypothesis was originally proposed to account for the observation that animals selecting among disparate foods often consume an excess of the more common types. The hypothesis states that animals searching for a particular cryptic food item focus on visual features that are characteristic of that item, thereby facilitating its discrimination from the background. A change in stimulus discriminability is not, however, the only feasible explanation for the effect. One alternative is a simple change in response bias, an increased predisposition to respond to food-related stimuli. Another possible hypothesis derives from the fact that the amount of time …
Sexual Dimorphism In The Kea Nestor Notabilis, Alan B. Bond, Kerry-Jayne Wilson, Judy Diamond
Sexual Dimorphism In The Kea Nestor Notabilis, Alan B. Bond, Kerry-Jayne Wilson, Judy Diamond
Papers in Behavior in Biological Sciences
Morphological differences between the sexes in Keas Nestor notabilis were quantified from a sample of 86 sexed museum specimens, nine sexed zoo captives and 129 live, wild-caught birds. The results demonstrate that Kea are sexually dimorphic. Males are about 5% larger than females in linear measurements of body size and their upper bills are on average 12-14% longer, with a slightly larger radius of curvature. The dimorphism in bill size was statistically independent of the difference in overall body size, suggesting the possibility of intersexual differences in niche utilisation. Culmen length appears to be a useful means for distinguishing sexes …