LIVIVO - Search results -

Search results

Result 1 - 10 of total 57

Search options

Article ; Online: A robotic falcon induces similar collective escape responses in different bird species.

Storms, Rolf F / Carere, Claudio / Musters, Robert / Hulst, Ronja / Verhulst, Simon / Hemelrijk, Charlotte K

2024 Volume 21, Issue 214, Page(s) 20230737

Abstract: Patterns of collective escape of a bird flock from a predator are fascinating, but difficult to study under natural conditions because neither prey nor predator is under experimental control. We resolved this problem by using an artificial predator ( ... ...

Abstract	Patterns of collective escape of a bird flock from a predator are fascinating, but difficult to study under natural conditions because neither prey nor predator is under experimental control. We resolved this problem by using an artificial predator (RobotFalcon) resembling a peregrine falcon in morphology and behaviour. We imitated hunts by chasing flocks of corvids, gulls, starlings and lapwings with the RobotFalcon, and compared their patterns of collective escape to those when chased by a conventional drone and, in case of starlings, hunted by wild peregrine falcons. Active pursuit of flocks, rather than only flying nearby by either the RobotFalcon or the drone, made flocks collectively escape more often. The RobotFalcon elicited patterns of collective escape in flocks of all species more often than the drone. Attack altitude did not affect the frequency of collective escape. Starlings escaped collectively equally often when chased by the RobotFalcon or a wild peregrine falcon. Flocks of all species reacted most often by collective turns, second most often by compacting and third by splitting into subflocks. This study demonstrates the potential of an artificial aerial predator for studying the collective escape behaviour of free-living birds, opening exciting avenues in the empirical study of prey-predator interactions.
MeSH term(s)	Animals ; Escape Reaction/physiology ; Falconiformes/physiology ; Robotics ; Predatory Behavior/physiology ; Birds/physiology ; Species Specificity
Language	English
Publishing date	2024-05-01
Publishing country	England
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	2156283-0
ISSN	1742-5662 ; 1742-5689
ISSN (online)	1742-5662
ISSN	1742-5689
DOI	10.1098/rsif.2023.0737
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

Article ; Online: Gossip promotes cooperation only when it is pro-socially motivated.

Testori, Martina / Hemelrijk, Charlotte K / Beersma, Bianca

Scientific reports

2022 Volume 12, Issue 1, Page(s) 4790

Abstract: Humans are often shown to cooperate with one another. Most of the mechanisms that foster cooperation among humans rely on reputation, which itself relies on the acquisition of information about other people's behaviors. Gossip has been proposed as a ... ...

Abstract	Humans are often shown to cooperate with one another. Most of the mechanisms that foster cooperation among humans rely on reputation, which itself relies on the acquisition of information about other people's behaviors. Gossip has been proposed as a cheap yet efficient tool to acquire information, and it has largely been proved to be an effective means to foster and maintain cooperation. However, empirical studies supporting this claim have ignored two aspects: (1) they often compared gossip to treatments in which no reputation was available, impeding a direct assessment of whether it is gossip that promotes cooperation or rather the introduction of a reputation system; and (2) they focused on pro-social gossip (e.g., gossip aimed at helping the receiver), neglecting the impact of other types of gossip. We show here that, in contrast with the widespread notion that gossip promotes cooperation, gossip mostly depletes cooperation compared to first-hand information. If lying is fruitful for individuals or if a group's behavior is largely uncooperative, gossip leads to negative reputational information and decreased cooperation.
MeSH term(s)	Communication ; Cooperative Behavior ; Humans
Language	English
Publishing date	2022-03-21
Publishing country	England
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	2615211-3
ISSN	2045-2322 ; 2045-2322
ISSN (online)	2045-2322
ISSN	2045-2322
DOI	10.1038/s41598-022-08670-7
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Article ; Online: Interrelationship among spatial cohesion, aggression rate, counter-aggression and female dominance in three lemur species

Seex, Lauren / Fichtel, Claudia / Kappeler, Peter M. / Hemelrijk, Charlotte K.

Behav Ecol Sociobiol. 2022 Oct., v. 76, no. 10 p.133-133

2022

Abstract: How social and ecological factors are associated with variation in dominance style across species of animals has been studied frequently, but the underlying processes are often not addressed. Theoretical research indicates that stronger spatial cohesion ... ...

Abstract	How social and ecological factors are associated with variation in dominance style across species of animals has been studied frequently, but the underlying processes are often not addressed. Theoretical research indicates that stronger spatial cohesion among individuals in a group causes a higher frequency of fighting and, thus, through the self-reinforcing effects of winning and losing fights, a stronger differentiation of the dominance hierarchy and dominance of females over more males. Our aim in the present paper is to study whether the same interrelationship among processes may underlie differences in dominance style among three species of lemur that differ in their degree of despotism: Lemur catta, Propithecus verreauxi and Eulemur rufifrons. We investigated their agonistic interactions and spatial cohesion based on 2752 h of observational data of 20 wild groups of these three species. We determined dominance style using the proportion of counter-aggression, with a lower proportion indicating a more despotic dominance style. We found that stronger spatial cohesion among individuals is associated with a higher rate of aggression, stronger despotism and dominance of females over more males. The results of our study emphasise the general importance of spatial cohesion in determining dominance style. SIGNIFICANCE STATEMENT: Theoretical studies have shown that the spatial configuration of individuals in a group influences the dominance style. In an agent-based model, DomWorld, individuals are guided by simple rules of grouping and fighting and emergent patterns of behaviour switch between resembling those of despotic or egalitarian primates depending on the degree of cohesion in groups. Yet this link has seldom been studied empirically. We, therefore, examine the relevance of spatial cohesion on patterns of behaviour of individuals in groups of three species of lemur. We confirm the predictions from the model and show that stronger spatial cohesion results in more frequent aggression, a more despotic dominance style and stronger female dominance over males. In light of this, we urge future research of animal dominance to include measures of cohesion.
Keywords	Eulemur ; Lemur catta ; aggression ; animals ; cohesion ; females ; models ; observational studies
Language	English
Dates of publication	2022-10
Size	p. 133.
Publishing place	Springer Berlin Heidelberg
Document type	Article ; Online
ZDB-ID	194510-5
ISSN	1432-0762 ; 0340-5443
ISSN (online)	1432-0762
ISSN	0340-5443
DOI	10.1007/s00265-022-03241-2
Database	NAL-Catalogue (AGRICOLA)

In stock of ZB MED Bonn / Germany

Z 78/731: Show issues

Order via subito

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Details ▾
- See ZB MED holdings
- Order with fees

Article: Reducing the bias due to unknown relationships in measuring the steepness of a dominance hierarchy

Saccà, Tommaso / Gort, Gerrit / van de Waal, Erica / Hemelrijk, Charlotte K.

Animal behaviour. 2022 July 04,

2022

Abstract: Measuring the steepness of a dominance hierarchy is important for classifying a social system in a continuum between egalitarian and despotic. For this, often the steepness-slope from de Vries et al. (Animal Behaviour, 2006, 71, 585–592) is often used. ... ...

Abstract	Measuring the steepness of a dominance hierarchy is important for classifying a social system in a continuum between egalitarian and despotic. For this, often the steepness-slope from de Vries et al. (Animal Behaviour, 2006, 71, 585–592) is often used. It compares the cardinal and ordinal dominance rank of each individual using the slope of the linear regression. The disadvantage of this measure is that the slope becomes lower the higher the proportion of unknown relationships (dyads without interactions). In the present paper, we investigate what causes this bias, and propose a solution. (1) We show that the bias is due to the treatment of unknown relationships by the dominance index currently used in this methodology, the David's score (namely by assuming, among other things, an equal number of wins and losses for both members of the pair). (2) Instead, using the Average Dominance Index (the average proportion of wins by each individual from all its opponents) reduces the bias due to unknown relationships, because it excludes these relationships, and (3) the standard error of the steepness-slope based on the Average Dominance Index is smaller. (4) The two indices (David's score and Average Dominance Index) result in similar steepness-slopes when all relationships are known. To compare the two indices we use empirical data (from four group-years of wild vervet monkeys, Chlorocebus pygerythrus) and data from a computational model on dominance interactions in a group (DomWorld). We conclude that the Average Dominance Index (compared to the David's score) is preferable for measuring the steepness-slope.
Keywords	Chlorocebus pygerythrus ; animal behavior ; bioinformatics ; regression analysis
Language	English
Dates of publication	2022-0704
Publishing place	Elsevier Ltd
Document type	Article
Note	Pre-press version
ZDB-ID	281-1
ISSN	0003-3472
ISSN	0003-3472
DOI	10.1016/j.anbehav.2022.09.002
Database	NAL-Catalogue (AGRICOLA)

In stock of ZB MED Bonn / Germany

Z 71/741: Show issues

Order via subito

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Details ▾
- See ZB MED holdings
- Order with fees

Article: Emergence of splits and collective turns in pigeon flocks under predation.

Papadopoulou, Marina / Hildenbrandt, Hanno / Sankey, Daniel W E / Portugal, Steven J / Hemelrijk, Charlotte K

Royal Society open science

2022 Volume 9, Issue 2, Page(s) 211898

Abstract: Complex patterns of collective behaviour may emerge through self-organization, from local interactions among individuals in a group. To understand what behavioural rules underlie these patterns, computational models are often necessary. These rules have ... ...

Abstract	Complex patterns of collective behaviour may emerge through self-organization, from local interactions among individuals in a group. To understand what behavioural rules underlie these patterns, computational models are often necessary. These rules have not yet been systematically studied for bird flocks under predation. Here, we study airborne flocks of homing pigeons attacked by a robotic falcon, combining empirical data with a species-specific computational model of collective escape. By analysing GPS trajectories of flocking individuals, we identify two new patterns of collective escape: early splits and collective turns, occurring even at large distances from the predator. To examine their formation, we extend an agent-based model of pigeons with a 'discrete' escape manoeuvre by a single initiator, namely a sudden turn interrupting the continuous coordinated motion of the group. Both splits and collective turns emerge from this rule. Their relative frequency depends on the angular velocity and position of the initiator in the flock: sharp turns by individuals at the periphery lead to more splits than collective turns. We confirm this association in the empirical data. Our study highlights the importance of discrete and uncoordinated manoeuvres in the collective escape of bird flocks and advocates the systematic study of their patterns across species.
Language	English
Publishing date	2022-02-23
Publishing country	England
Document type	Journal Article
ZDB-ID	2787755-3
ISSN	2054-5703
ISSN	2054-5703
DOI	10.1098/rsos.211898
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Article ; Online: Self-organization of collective escape in pigeon flocks.

Papadopoulou, Marina / Hildenbrandt, Hanno / Sankey, Daniel W E / Portugal, Steven J / Hemelrijk, Charlotte K

PLoS computational biology

2022 Volume 18, Issue 1, Page(s) e1009772

Abstract: Bird flocks under predation demonstrate complex patterns of collective escape. These patterns may emerge by self-organization from local interactions among group-members. Computational models have been shown to be valuable for identifying what behavioral ...

Abstract	Bird flocks under predation demonstrate complex patterns of collective escape. These patterns may emerge by self-organization from local interactions among group-members. Computational models have been shown to be valuable for identifying what behavioral rules may govern such interactions among individuals during collective motion. However, our knowledge of such rules for collective escape is limited by the lack of quantitative data on bird flocks under predation in the field. In the present study, we analyze the first GPS trajectories of pigeons in airborne flocks attacked by a robotic falcon in order to build a species-specific model of collective escape. We use our model to examine a recently identified distance-dependent pattern of collective behavior: the closer the prey is to the predator, the higher the frequency with which flock members turn away from it. We first extract from the empirical data of pigeon flocks the characteristics of their shape and internal structure (bearing angle and distance to nearest neighbors). Combining these with information on their coordination from the literature, we build an agent-based model adjusted to pigeons' collective escape. We show that the pattern of turning away from the predator with increased frequency when the predator is closer arises without prey prioritizing escape when the predator is near. Instead, it emerges through self-organization from a behavioral rule to avoid the predator independently of their distance to it. During this self-organization process, we show how flock members increase their consensus over which direction to escape and turn collectively as the predator gets closer. Our results suggest that coordination among flock members, combined with simple escape rules, reduces the cognitive costs of tracking the predator while flocking. Such escape rules that are independent of the distance to the predator can now be investigated in other species. Our study showcases the important role of computational models in the interpretation of empirical findings of collective behavior.
MeSH term(s)	Animals ; Columbidae/physiology ; Computational Biology ; Computer Simulation ; Escape Reaction/physiology ; Mass Behavior ; Species Specificity
Language	English
Publishing date	2022-01-10
Publishing country	United States
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	2193340-6
ISSN	1553-7358 ; 1553-734X
ISSN (online)	1553-7358
ISSN	1553-734X
DOI	10.1371/journal.pcbi.1009772
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Article ; Online: Deterrence of birds with an artificial predator, the RobotFalcon.

Storms, Rolf F / Carere, Claudio / Musters, Robert / van Gasteren, Hans / Verhulst, Simon / Hemelrijk, Charlotte K

Journal of the Royal Society, Interface

2022 Volume 19, Issue 195, Page(s) 20220497

Abstract: Collisions between birds and airplanes can damage aircrafts, resulting in delays and cancellation of flights, costing the international civil aviation industry more than 1.4 billion US dollars annually. Driving away birds is therefore crucial, but the ... ...

Abstract	Collisions between birds and airplanes can damage aircrafts, resulting in delays and cancellation of flights, costing the international civil aviation industry more than 1.4 billion US dollars annually. Driving away birds is therefore crucial, but the effectiveness of current deterrence methods is limited. Live avian predators can be an effective deterrent, because potential prey will not habituate to them, but live predators cannot be controlled entirely. Thus, there is an urgent need for new deterrence methods. We developed the RobotFalcon, a device modelled after the peregrine falcon, and tested its effectiveness to deter flocks of corvids, gulls, starlings and lapwings. We compared its effectiveness with that of a drone, and of conventional methods routinely applied at a military airbase. The RobotFalcon scared away bird flocks from fields immediately, and these fields subsequently remained free of bird flocks for hours. The RobotFalcon outperformed the drone and the best conventional method at the airbase (distress calls). Importantly, there was no evidence that bird flocks habituated to the RobotFalcon over the course of the fieldwork. We conclude that the RobotFalcon is a practical and ethical solution to drive away bird flocks with all advantages of live predators but without their limitations.
MeSH term(s)	Animals ; Predatory Behavior ; Birds ; Charadriiformes ; Fear
Language	English
Publishing date	2022-10-26
Publishing country	England
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	2156283-0
ISSN	1742-5662 ; 1742-5689
ISSN (online)	1742-5662
ISSN	1742-5689
DOI	10.1098/rsif.2022.0497
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Article: Sexual size dimorphism, prey morphology and catch success in relation to flight mechanics in the peregrine falcon: a simulation study.

Mills, Robin / Taylor, Graham K / Hemelrijk, Charlotte K

Journal of avian biology

2019 Volume 50, Issue 3

Abstract: In common with many other raptors, female peregrine ... ...

Abstract	In common with many other raptors, female peregrine falcons
Language	English
Publishing date	2019-03-20
Publishing country	Denmark
Document type	Journal Article
ZDB-ID	2028018-X
ISSN	1600-048X ; 0908-8857
ISSN (online)	1600-048X
ISSN	0908-8857
DOI	10.1111/jav.01979
Database	MEDical Literature Analysis and Retrieval System OnLINE

Full text online

Accessible to users with ZB MED library card

Order via subito

Details ▾
- Full text online
- Order with fees

Article ; Online: Diffusion and topological neighbours in flocks of starlings: relating a model to empirical data.

Hemelrijk, Charlotte K / Hildenbrandt, Hanno

PloS one

2015 Volume 10, Issue 5, Page(s) e0126913

Abstract: Moving in a group while avoiding collisions with group members causes internal dynamics in the group. Although these dynamics have recently been measured quantitatively in starling flocks (Sturnus vulgaris), it is unknown what causes them. Computational ... ...

Abstract	Moving in a group while avoiding collisions with group members causes internal dynamics in the group. Although these dynamics have recently been measured quantitatively in starling flocks (Sturnus vulgaris), it is unknown what causes them. Computational models have shown that collective motion in groups is likely due to attraction, avoidance and, possibly, alignment among group members. Empirical studies show that starlings adjust their movement to a fixed number of closest neighbours or topological range, namely 6 or 7 and assume that each of the three activities is done with the same number of neighbours (topological range). Here, we start from the hypothesis that escape behavior is more effective at preventing collisions in a flock when avoiding the single closest neighbor than compromising by avoiding 6 or 7 of them. For alignment and attraction, we keep to the empirical topological range. We investigate how avoiding one or several neighbours affects the internal dynamics of flocks of starlings in our computational model StarDisplay. By comparing to empirical data, we confirm that internal dynamics resemble empirical data more closely if flock members avoid merely their single, closest neighbor. Our model shows that considering a different number of interaction partners per activity represents a useful perspective and that changing a single parameter, namely the number of interaction partners that are avoided, has several effects through selforganisation.
MeSH term(s)	Models, Theoretical
Language	English
Publishing date	2015-05-18
Publishing country	United States
Document type	Journal Article
ZDB-ID	2267670-3
ISSN	1932-6203 ; 1932-6203
ISSN (online)	1932-6203
ISSN	1932-6203
DOI	10.1371/journal.pone.0126913
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Article: Modelling non-attentional visual information transmission in groups under predation

van Weerden, J. Fransje / Verbrugge, Rineke / Hemelrijk, Charlotte K

Ecological modelling. 2020 Sept. 01, v. 431

2020

Abstract: Group living is of benefit to foraging individuals by improving their survival, through passive risk dilution by sheer numbers and through increasingly more active processes, ranging from cue transmission to alarm calling. Cue transmission of information ...

Abstract	Group living is of benefit to foraging individuals by improving their survival, through passive risk dilution by sheer numbers and through increasingly more active processes, ranging from cue transmission to alarm calling. Cue transmission of information within a group cannot easily be tracked in the field, but can be studied by modelling. An unintentional visual cue can be given by a fleeing action, and when it occurs in the visual field of an individual, can by contagion incite it to flee as well, making such a cue functional in anti-predator warning. The visual field is limited not only by morphology, causing a blind angle at the back, but also by behaviour. For instance, foraging with the head down can cause an extra “blind” angle in front for cues from other individuals, changing an unobstructed frontal visual field to a split lateral shape.The questions of the present study are: how do visual fields, in terms of their size and blind angles, influence survival of individuals in a group through their effect on non-attentional reception of cues to danger among group members after attentional detection of a predator, and how can we quantify this?We use an agent-based spatially explicit model to investigate the effect of contagious fleeing after detection of predators on survival rate. This model is a bottom-up model of foraging agents in a simple environment, where only assumptions about basic competences are made. We vary the size and the shape of the visual field (lateral, with the additional frontal “blind” angle, versus a frontal continuous view), the group size, the movement probability, and the style of movement (regular movement or start-stop movement) in residential groups. We devise a measure for the transmission rate and we measure the length of the transmission chains.We find that, as expected, in a residential group, a larger visual field enhances survival rate. Moreover, a lateral field is more effective than a frontal field of the same total size because it increases the field of vision and therefore the non-attentional reception of visual cues about danger during, for instance, foraging, for all but the largest visual fields. This is demonstrated by the higher transmission rates and longer chains of transmission for lateral fields. Better transmission for lateral visual fields results in more synchronized fleeing behaviour. As long as the visual field is large enough, having a blind angle in front does not detract from sufficiently effective transmission. These findings should be taken into account in empirical studies of vigilance in groups of foraging animals.
Keywords	animals ; empirical research ; foraging ; group size ; head ; models ; predation ; predators ; risk ; survival rate ; vision
Language	English
Dates of publication	2020-0901
Publishing place	Elsevier B.V.
Document type	Article
ZDB-ID	191971-4
ISSN	0304-3800
ISSN	0304-3800
DOI	10.1016/j.ecolmodel.2020.109073
Database	NAL-Catalogue (AGRICOLA)

In stock of ZB MED Bonn / Germany

Z 77/705: Show issues

Order via subito

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Details ▾
- See ZB MED holdings
- Order with fees

To top

More links

Kategorien

Order via subito

More links

Kategorien

Order via subito

More links

Kategorien

In stock of ZB MED Bonn / Germany

Order via subito

Inter-library loan at ZB MED

More links

Kategorien

In stock of ZB MED Bonn / Germany

Order via subito

Inter-library loan at ZB MED

More links

Kategorien

Order via subito

More links

Kategorien

Order via subito

More links

Kategorien

Order via subito

Full text online

More links

Kategorien

Order via subito

More links

Kategorien

Order via subito

More links

Kategorien

In stock of ZB MED Bonn / Germany

Order via subito

Inter-library loan at ZB MED