When pigeons in motion lose sight of their food: behaviour on visible displacement tasks revisited

2007 ◽  
Vol 85 (5) ◽  
pp. 644-652 ◽  
Author(s):  
C. Krachun ◽  
C.M.S. Plowright
Keyword(s):  
Memory Load ◽  
Columba Livia ◽  
Food Dish ◽  
Object A ◽  
Subject Design ◽  
Shortest Route ◽  
Visual Access ◽  
Visible Displacement ◽  
Access To Food ◽  
Do So

In traditional visible displacement tasks, animals view an object as it is moved out of their sight, but either the object moves behind an occluder or an occluder moves in front of it. Here we present a more ecologically realistic visible displacement task for pigeons ( Columba livia (Gmelin, 1789)) in which it was the animal that occluded the object, a food dish in this case, by virtue of its own motion. In a branched maze, pigeons had visual access to food, which they would lose from view as they moved through the maze. A within-subject design was used whereby the task was presented first in descending order of difficulty (i.e., decreasing memory load owing to the opening of (i) gaps and (ii) windows in the walls of the maze), and followed 10 months later by an ascending order. When the food was visible at all times through windows and gaps, pigeons would make turns in the maze that would bring them closer to the food (i.e., they chose the shortest route above chance levels). In general, they failed to do so when the food was lost from view, but there was one exception at the end of the study (the second time that there were gaps but no windows): there was a significant tendency for the last two turns that brought the bird out of the maze to be the shortest route to the food. The pigeons may have learned to take advantage of opportunities to lighten their memory load.

Reading Your Mind While You Are Reading—Evidence for Spontaneous Visuospatial Perspective Taking During a Semantic Categorization Task

2018 ◽  
Vol 29 (4) ◽  
pp. 614-622 ◽  
Author(s):  
Martin Freundlieb ◽  
Ágnes M. Kovács ◽  
Natalie Sebanz
Keyword(s):  
Perspective Taking ◽  
Point Of View ◽  
Categorization Task ◽  
Semantic Categorization ◽  
Physical Context ◽  
Visual Access ◽  
Human Adults ◽  
Mental Space ◽  
The Right ◽  
Do So

Recent studies have demonstrated people’s propensity to adopt others’ visuospatial perspectives (VSPs) in a shared physical context. The present study investigated whether spontaneous VSP taking occurs in mental space where another person’s perspective matters for mental activities rather than physical actions. Participants sat at a 90° angle to a confederate and performed a semantic categorization task on written words. From the participants’ point of view, words were always displayed vertically, while for the confederate, these words appeared either the right way up or upside down, depending on the confederate’s sitting position. Participants took longer to categorize words that were upside down for the confederate, suggesting that they adopted the confederate’s VSP without being prompted to do so. Importantly, the effect disappeared if the other’s visual access was impeded by opaque goggles. This demonstrates that human adults show a spontaneous sensitivity to others’ VSP in the context of mental activities, such as joint reading.

scholarly journals Female bed bugs (Cimex lectularius L) anticipate the immunological consequences of traumatic insemination via feeding cues

2019 ◽  
Vol 116 (29) ◽  
pp. 14682-14687 ◽  
Author(s):  
Michael T. Siva-Jothy ◽  
Weihao Zhong ◽  
Richard Naylor ◽  
Louise Heaton ◽  
William Hentley ◽  
...  
Keyword(s):  
Temporal Correlation ◽  
Copulatory Organ ◽  
Lifetime Reproductive Success ◽  
Bed Bugs ◽  
Temporal Cues ◽  
Infection Cycles ◽  
Fitness Benefits ◽  
Access To Food ◽  
Induced Immunity ◽  
Do So

Not all encounters with pathogens are stochastic and insects can adjust their immune management in relation to cues associated with the likelihood of infection within a life cycle as well as across generations. In this study we show that female insects (bed bugs) up-regulate immune function in their copulatory organ in anticipation of mating by using feeding cues. Male bed bugs only mate with recently fed females and do so by traumatic insemination (TI). Consequently, there is a tight temporal correlation between female feeding and the likelihood of her being infected via TI. Females that received predictable access to food (and therefore predictable insemination and infection cycles) up-regulated induced immunity (generic antibacterial activity) in anticipation of feeding and mating. Females that received unpredictable (but the same mean periodicity) access to food did not. Females that anticipated mating-associated immune insult received measurable fitness benefits (survival and lifetime reproductive success) despite laying eggs at the same rate as females that were not able to predict these cycles. Given that mating is a time of increased likelihood of infection in many organisms, and is often associated with temporal cues such as courtship and/or feeding, we propose that anticipation of mating-associated infection in females may be more widespread than is currently evidenced.

scholarly journals Performance on a Means-End Task by Asian Elephants (Elephas maximus) in a Positive Reinforcement-Based Protected-Contact Setting

2016 ◽  
Vol 29 ◽  
Author(s):  
Lauren E. Highfill ◽  
Jessica M. Spencer ◽  
Otto Fad ◽  
Ann Marie Arnold
Keyword(s):  
Positive Reinforcement ◽  
Elephas Maximus ◽  
Original Research ◽  
Distant Object ◽  
Asian Elephants ◽  
Object A ◽  
Visual Access ◽  
Relevant Variables ◽  
Condition C ◽  
And Training

The current study tested six Asian elephants (Elephas maximus) on a means-end behavioral task of pulling a support to retrieve a distant object; a systematic replication of the Irie-Sugimoto et al. (2008) study. The paradigm was somewhat modified from the original research to accommodate a protected contact setting, reduce the total number of trials, and one condition was excluded. Each elephant was tested on three conditions of increasing difficulty. Specifically, subjects were asked to select from a choice of two trays where one intact tray was baited with a highly-valued produce item and the other was A) empty; B) baited adjacent to the tray; and C) baited on the far side of a break in the tray. Results indicated that the elephants met or exceeded the criteria established for conditions A and B, but performed at chance levels on condition C. These data are contrasted with those of the original study where one elephant met criteria for all three conditions. We discuss potentially relevant variables affecting performance including differences in visual access to the trays, motivation levels, and training style.

scholarly journals Do Tonkean macaques (Macaca tonkeana) perceive what conspecifics do and do not see?

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1693 ◽  
Author(s):  
Charlotte Canteloup ◽  
Emilie Piraux ◽  
Nicolas Poulin ◽  
Hélène Meunier
Keyword(s):  
Head Start ◽  
Perspective Taking ◽  
Great Apes ◽  
Food Competition ◽  
Movement Direction ◽  
Visual Perspective ◽  
Macaca Tonkeana ◽  
Visual Perspective Taking ◽  
Visual Access ◽  
Access To Food

The understanding of the visual perception of others, also named visual perspective taking, is a component of Theory of Mind. Although strong evidence of visual perspective taking has been reported in great apes, the issue is more open to discussion in monkeys. We investigated whether Tonkean macaques (Macaca tonkeana) know what conspecifics do and do not see, using a food competition paradigm originally developed in great apes. We tested individuals in pairs, after establishing the dominance relationship within each pair. Twenty-one pairs were tested in four different conditions. In one condition, the subordinate had the choice between two pieces of food, one that was visible only to it and another that was also visible to the dominant. It was predicted that if the subordinate understands that the dominant cannot see both pieces of food because one is hidden from its view, the subordinate should preferentially go for the food visible only to itself. In the three other conditions, we varied the temporal and visual access to food for both individuals, to control for alternative explanations based on dominance. We recorded the first movement direction chosen by subjects, i.e. towards a) visible food b) hidden food or c) elsewhere; and the outcome of the test, i.e. the quantity of food obtained. Results showed that subordinates moved preferentially for the hidden food when released simultaneously with the dominant and also with a head start on the dominant. By contrast, dominants’ choices of the two pieces of food were random. We also describe and discuss some of the strategies used by subordinates in these tests. According to the whole of our results, Tonkean macaques seem capable of visual perspective taking despite the fact that a low-level explanation as behavior reading has not been totally excluded.

Across the Chattahoochee, July 17–18

2017 ◽  
Author(s):  
Earl J. Hess
Keyword(s):  
Peach Tree ◽  
The South ◽  
South Side ◽  
Shortest Route ◽  
Army Of Tennessee ◽  
The City ◽  
Do So ◽  
Chattahoochee River

On July 17, Sherman moved all of his troops to the south side of the Chattahoochee River and marched on Atlanta, with James B. McPherson's Army of the Tennessee moving the longest distance to reach Decatur east of Atlanta and tear up the Georgia Railroad as it advanced toward the city. This cut one of the three railroads Johnston relied on to feed his army in Atlanta. George H. Thomas' Army of the Cumberland had the shortest route to march, crossing the Chattahoochee near its junction with Peach Tree Creek, moving to Buck Head, and then marching south toward Atlanta. John M. Schofield's Army of the Ohio tried to fill in the distance between those two forces. As the Federals advanced with minor skirmishing against a screen of Confederate cavalry, Davis decided to relieve Johnston of command and elevate John Bell Hood to replace him. Hood, taken by surprise, tried to convince Davis to change his mind or at least postpone the change in commanders but the Confederate president refused to do so. Hood finally assumed his new command on July 18 and tried to prepare the Army of Tennessee to meet Sherman's advance.

scholarly journals Pembuatan Direktori Lokasi Bermain Skateboarding di Sumatera Barat

2019 ◽  
Vol 8 (1) ◽  
pp. 82
Author(s):  
Dian Mega Putra ◽  
Desriyeni Desriyeni
Keyword(s):  
Data Analysis ◽  
Data Collection ◽  
Literature Study ◽  
Precise Information ◽  
Object A ◽  
Descriptive Research ◽  
West Sumatra ◽  
The Right ◽  
Clear Information ◽  
Do So

AbstractWriting this paper aims to create a directory of locations for skateboarding in West Sumatra. The method used in this paper is descriptive research, which examines a group of people, an object, a condition, a thought, or a class of events in the present. Data collection is done by observation, interview, and literature study. Based on data analysis, it can be concluded as follows. First, the obstacles in making a skateboarding directory location in West Sumatra can be described as follows. (a) the writer has difficulty finding a clear place about the location of skateboarding. These constraints are due to the absence of a clear pointer or direction to a skateboarding location. (b) the distance from the downtown or downtown. These constraints are due to inadequate access to locations. The author must ask and explain to the surrounding community in detail in a location in order to get to the point where to skateboard. (c), the authors find it difficult to find the right sources for more detailed information on a skateboarding location. The existence of these obstacles is due to ignorance of the community and skateboarding community about the place. The author only gets some clear information when making observations. Second, the author's attempt to do so is as follows. (a) the author does his best to make clear road and road directions to a skateboarding location with the help of the surrounding community and the communities in the place. With the help of the community and community in making instructions at a predetermined point or better known by the community. (b) the author tries to minimize the distance to the location of skateboarding by asking the informant or the right informant at a skateboarding location. (c) the author tries his best to do interviews with several people to get clear and precise information about a skateboarding location. The resource person can come from the community itself or the community around the location.Keywords: directory, skateboarding, West Sumatera

Effects of pineal indoles and parachlorophenylalanine on seasonal reproduction in the pigeon

1996 ◽  
Vol 199 (4) ◽  
pp. 793-800
Author(s):  
A Ramachandran ◽  
M Patel ◽  
C Patel
Keyword(s):  
Columba Livia ◽  
Follicular Epithelium ◽  
Seasonal Reproduction ◽  
Pineal Indoles ◽  
Testicular Regression ◽  
Thyroid Glands ◽  
Colloid Retention ◽  
Serum Thyroid Hormone ◽  
Thyroid Hormone Levels ◽  
Do So

The effect of melatonin, methoxytryptophol (ML), methoxytryptamine (MT) and parachlorophenylalanine (p-CPA) on the mass and histology of the testes and the adrenal and thyroid glands and on serum thyroid hormone levels have been studied in the recrudescent phase of the feral pigeon Columba livia. All the pineal indoles showed a common anti-gonadal effect, resulting in the arrest of spermatogenesis and the degeneration of germ cells. Treatment with melatonin resulted in adreno-cortical enlargement and medullary hypertrophy, whereas ML, MT and p-CPA induced medullary enlargement and hypertrophy without having much influence on the cortex. Treatment with melatonin and ML brought about colloid retention in the thyroid follicles, while MT and p-CPA induced colloid depletion and hypertrophy of the follicular epithelium. From the present study, it can be concluded that both pineal indoles and p-CPA induce testicular regression in the breeding phase but do so by different mechanisms.

Dominance affects resource partitioning in pigeons, but pair bonds do not

1996 ◽  
Vol 74 (5) ◽  
pp. 833-840 ◽  
Author(s):  
David Robichaud ◽  
Louis Lefebvre ◽  
Lucie Robidoux
Keyword(s):  
Resource Partitioning ◽  
Dominance Rank ◽  
Columba Livia ◽  
Pair Bonds ◽  
In Captivity ◽  
Lower Ranking ◽  
Opposite Sex ◽  
Feeding Trials ◽  
Access To Food ◽  
Diet Shifts

Pigeons (Columba livia) show individual feeding specializations both in the field and in captivity. In competitive feeding conditions, these specializations change in a way that decreases dietary overlap between birds. We examine two potential status determinants of feeding competition, dominance and pair bonds. In pigeons, pair bonds are used in aggressive feeding coalitions at defendable patches, while dominance affects both feeding rate and priority of access to food. We compared the seed choices of pigeons feeding alone and in competitive conditions with those of a conspecific. In experiment 1, the competitor was either the mate or a familiar nonmate of the opposite sex; in experiment 2, the dominance rank of the competitors was known from a round-robin series of dyadic encounters in the presence of a defendable feeder. Pair bonds had no effect on competitive diet shifts, but dominance did: in competition, lower ranking pigeons ate less of the seed type they specialized on when feeding alone, while higher ranking pigeons ate more. Confirming previous results on resource partitioning, food choice showed less overlap between individuals in competition than in solitary feeding trials, but the magnitude of the change was not proportional to initial overlap.

scholarly journals EXPRESS: Do cognitive load and ADHD traits affect the tendency to prioritise social information in scenes?

2021 ◽  
pp. 174702182110664
Author(s):  
Astrid Priscilla Martinez-Cedillo ◽  
Kevin Dent ◽  
Tom Foulsham
Keyword(s):  
Memory Load ◽  
Flanker Task ◽  
Load Condition ◽  
Object A ◽  
Social Object ◽  
Complex Stimuli ◽  
The Social ◽  
Complex Scenes ◽  
Low Load ◽  
Social Area

We report two experiments investigating the effect of working memory (WM) load on selective attention. Experiment 1 was a modified version of Lavie et al. (2004) and confirmed that increasing memory load disrupted performance in the classic flanker task. Experiment 2 used the same manipulation of WM load to probe attention during the viewing of complex scenes, while also investigating individual differences in ADHD traits. In the image viewing task, we measured the degree to which fixations targeted each of two crucial objects: (1) a social object (a person in the scene) and (2) a non-social object of higher or lower physical salience. We compared the extent to which increasing WM load would change the pattern of viewing of the physically salient and socially salient objects. If attending to the social item requires greater default voluntary top-down resources, then the viewing of social objects should show stronger modulation by WM load compared to viewing of physically salient objects. The results showed that the social object was fixated to a greater degree than the other object (regardless of physical saliency). Increased saliency drew fixations away from the background leading to slightly increased fixations on the non-social object, without changing fixations on the social object. Increased levels of ADHD-like traits were associated with fewer fixations on the social object, but only in the high salient, low load condition. Importantly, WM load did not affect number of fixations on the social object. Such findings suggest rather surprisingly that attending to a social area in complex stimuli is not dependent on the availability of voluntary topdown resources.

scholarly journals Disability, Access to Food and the UN CRPD: Navigating Discourses of Human Rights in the Netherlands

2018 ◽  
Vol 6 (1) ◽  
pp. 51-60 ◽  
Author(s):  
Mitzi Waltz ◽  
Tanja Mol ◽  
Elinor Gittins ◽  
Alice Schippers
Keyword(s):  
The Netherlands ◽  
Social Economic ◽  
Policy Research ◽  
Equal Access ◽  
Persons With Disabilities ◽  
Physical Barriers ◽  
Eu Policies ◽  
Access To Food ◽  
Developed Nations ◽  
Do So

In 2016, the Netherlands ratified the UN Convention on the Rights of Persons with Disabilities (UN CRPD), one of the last developed nations to do so. In this article, we explore how equal access to food provides a lens through which barriers to implementing a rights-based approach to disability equality can be examined in countries that are historically resistant to such discourses. Through a literature review, policy research, and interviews with disabled people, representatives of disabled people’s organisations, Dutch legal scholars, food researchers, and foodbanks, we have explored barriers to equal food access in the Netherlands, and current approaches to overcoming social, economic and physical barriers. Our analysis indicates that implementation of the UN CRPD and other relevant international and EU policies continues to be limited in the Netherlands due to narrow interpretations, leading to policies and practices that do not foster equal access to resources and environments. Dutch understandings of disability equality are evolving, but encounter opposition from an entrenched system of separation and resistance to mandating change, including a reluctance to even collect data about inequality. From this basis, we identify knowledge gaps and make recommendations for steps the Netherlands could take to ensure equal access to food.

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