The International Journal of Comparative Psychology is sponsored by the International Society for Comparative Psychology. It is a peer-reviewed open-access digital journal that publishes studies on the evolution and development of behavior in all animal species. It accepts research articles and reviews, letters and audiovisual submissions.
Volume 19, Issue 3, 2006
Spatial Learning in Dragonflies
Spatial learning is evident in dragonflies on a variety of spatial scales. Mature dragonflies must be able to locate a variety of features in the habitat that are critical to survival and reproduction, including sites for breeding, foraging, roosting, and thermoregulating. In many species, these sites do not coincide in space. Because individuals may repeatedly use particular sites for different activities, they must learn both the locations of these sites and routes among them. Further evidence of spatial memory in dragonflies is provided by their site specificity on a finer scale. Breeding males, for example, often are faithful not only to a particular area, but to a specific territory site within that area. Males appear to become faithful to a territory site through localization, a process during which they explore the site and develop a spatial map of the location of the territory and its resources. Males also respond to their interactions with other individuals, adjusting both their choice of territories and their space use within their territories to reflect those interactions. In eastern amberwing dragonflies ( Perithemis tenera ), males are not faithful to territories on which they have lost a fight with another male; in contrast, males are more likely to be faithful to territories on which they successfully mated than to territories on which they obtained no matings. Similarly, while on territories, male amberwings adjust their position in response to negative and positive interactions. They move away from the side of the territory from which neighbors most frequently intruded, and they move toward locations from which they pursued a female. Territorial amberwings thus modify their space use at both the territory and within-territory spatial scale in response to their social environment. Their responses are consistent with the hypothesis that they learn from their positive and negative experiences and adjust their future space use accordingly. Further study of spatial learning in dragonflies would greatly enhance studies of dragonflies’ behavior and ecology, and help us understand learning in general.
Geographic Variation in a Spider’s Ability to Solve a Confinement Problem by Trial and Error
Portia is a genus of web-invading araneophagic (spider eating) jumping spiders known from earlier studies to derive aggressive-mimicry signals by using a generate-and-test (trial and error) algorithm. We studied individuals of Portia labiata from two populations (Los Baños and Sagada) in the Philippines that have previously been shown to differ in the level to which they rely on trial-and-error derivation of signals for prey capture (Los Baños relied on trial and error more strongly than Sagada P. labiata ). Here we investigated P. labiata’s use of trial and error in a novel situation (a confinement problem: how to escape from an island surrounded by water) that is unlikely to correspond closely to anything the spider would encounter in nature. During Experiment 1, spiders chose between two potential escape tactics (leap or swim), one of which was set at random to fail (brought spider no closer to edge of tray) and the other of which was set for partially succeeding (brought spider closer to edge of tray). By using trial and error, the Los Baños P. labiata solved the confinement problem significantly more often than the Sagada P. labiata in Experiment 1, both when the correct choices were positively reinforced (i.e., when the spider was moved closer to edge of tray) and when incorrect choices were punished (i.e., when the spider got no closer to edge of tray). In Experiment 2, the test individual’s first choice was always set to fail, and P. labiata was given repeated opportunities to respond to feedback, yet the Sagada P. labiata continued to place little reliance on trial and error for solving the confinement problem. That the Los Baños P. labiat a relied more strongly on trial-anderror problem solving than the Sagada P. labiata has now been demonstrated across two different tasks.
Learning in Stomatopod Crustaceans
The stomatopod crustaceans, or mantis shrimps, are marine predators that stalk or ambush prey and that have complex intraspecific communication behavior. Their active lifestyles, means of predation, and intricate displays all require unusual flexibility in interacting with the world around them, implying a well-developed ability to learn. Stomatopods have highly evolved sensory systems, including some of the most specialized visual systems known for any animal group. Some species have been demonstrated to learn how to recognize and use novel, artificial burrows, while others are known to learn how to identify novel prey species and handle them for effective predation. Stomatopods learn the identities of individual competitors and mates, using both chemical and visual cues. Furthermore, stomatopods can be trained for psychophysical examination of their sensory abilities, including demonstration of color and polarization vision. These flexible and intelligent invertebrates continue to be attractive subjects for basic research on learning in animals with relatively simple nervous systems.
Learning of Abstract Concepts and Rules by the Honeybee
Despite the tiny brain of the honeybee, some remarkable higher cognitive functions have emerged from this assembly of about one million neurons. Work on the honeybee over the past decade is beginning to suggest that insects may not be the simple, reflexive creatures that they were once believed to be. Bees display perceptual and “cognitive” capacities that are surprisingly rich, complex and flexible. This article reviews the recent progress on the honeybee’s ability to learn and use abstract rules and concepts, to categorize visual objects in various ways, and to memorize task-specific information while navigating through their environment. This review is not intended to be exhaustive. Rather, it highlights important advances in our understanding of the processes underlying the bee’s remarkable behaviors.
Visual Search and Decision Making in Bees: Time, Speed, and Accuracy
An insect searching a meadow for flowers may detect several flowers from different species per second, so the task of choosing the right flowers rapidly is not trivial. Here we apply concepts from the field of visual search in human experimental psychology to the task a bee faces in searching a meadow for familiar flowers, and avoiding ‘‘distraction’’ by unknown or unrewarding flowers. Our approach highlights the importance of visual information processing for understanding the behavioral ecology of foraging. Intensity of illuminating light, target contrast with background (both chromatic and achromatic), and number of distractors are all shown to have a direct influence on decision times in behavioral choice experiments. To a considerable extent, the observed search behavior can be explained by the temporal and spatial properties of neuronal circuits underlying visual object detection. Our results also emphasize the importance of the time dimension in decision making. During visual search in humans, improved accuracy in solving discrimination tasks comes at a cost in response time, but the vast majority of studies on decision making in animals have focused on choice accuracy, not speed. We show that in behavioral choice experiments in bees, there is a tight link between the two. We demonstrate both between-individual and within- individual speed-accuracy tradeoffs, whereby bees exhibit considerable behavioral flexibility in solving visual search tasks. Motivation is an important factor in selection of behavioral strategies for a search task, and sensory discrimination capabilities may be underestimated by studies that quantify accuracy of behavioral choice but neglect the temporal dimension.
Prospective and Retrospective Learning in Honeybees
We focus on non-elemental forms of learning in honeybees in order to answer the question of whether retrospective learning can be found in an insect. We analyze three different forms of learning: category learning, rule learning and backward blocking. We provide examples showing that honeybees demonstrate these three forms of learning and propose that causal retrospection underlies them to different extents. We argue that an elemental associative account explains category learning whereas rule learning may require retrospection. Backward blocking, on the other hand, admits interpretations based on prospective learning. Consequently, because animals, including honeybees, solve these three types of problems, distinguishing between species on the basis of these capacities is inappropriate.
Deleterious Effects of Low Temperature Exposure on Learning Expression in a Parasitoid
In this paper, we review the learning capacities of insect parasitoids. We present data on the learning capacity of the parasitoid wasp, Anaphes victus (Hymenoptera: Mymaridae), in the host (egg) discrimination process. In addition, we examine the effect of low temperature exposure on the wasp’s learning. Our results showed that A. victu s females learned rapidly to recognize their own chemical cues that they left on the host eggs, and retained this learning from patch to patch. Conspecific chemical cues left on the eggs took more time to be learned, but two learning trials induced a prolonged memory for the cues. Our results also showed that the use of learned, conspecific chemical cues was more affected by cold exposure than was the use of learned personal cues.