dear enemy effect
Recently Published Documents


TOTAL DOCUMENTS

25
(FIVE YEARS 9)

H-INDEX

8
(FIVE YEARS 1)

2022 ◽  
Vol 184 ◽  
pp. 19-26
Author(s):  
Jan Jedlikowski ◽  
Marcin Polak ◽  
Paweł Ręk

2021 ◽  
Author(s):  
Michael S. Reichert ◽  
Jodie M.S. Crane ◽  
Gabrielle L. Davidson ◽  
Eileen Dillane ◽  
Ipek G. Kulahci ◽  
...  

ABSTRACTTerritorial animals often exhibit the dear enemy effect, in which individuals respond less aggressively to neighbours than to other individuals. The dear enemy effect is hypothesized to be adaptive by reducing unnecessary aggressive interactions with individuals that are not a threat to territory ownership. A key prediction of this hypothesis, that individual fitness will be affected by variation in the speed and extent to which individuals reduce their aggression towards neighbours relative to strangers, has never been tested. We used a series of song playbacks to measure the change in response of male great tits on their breeding territories to a simulated establishment of a neighbour on an adjacent territory. Males reduced their approach to the speaker and sang fewer songs on later repetitions of the playback trials, consistent with a dear enemy effect through habituation learning. However, not all males discriminated between the neighbour and stranger playbacks at the end of the series of trials, and there was evidence that individuals consistently differed from one another in performing this discrimination. We monitored nests and analysed offspring paternity to determine male reproductive success. Unexpectedly, individuals that exhibited dear enemy behaviour towards the simulated neighbour did not have higher reproductive success, and in fact one measure, total offspring biomass, was lower for individuals that showed the dear enemy effect. Although the general capability to recognize neighbours is most likely adaptive, it seems that individuals who decrease their responsiveness to familiar neighbours too quickly may gain no advantage or even be at a disadvantage.


2021 ◽  
Author(s):  
James P Tumulty ◽  
Zachary K Lange ◽  
Mark A Bee

Animals recognize familiar individuals to perform a variety of important social behaviors. Social recognition is often mediated by communication between signalers who produce signals that contain identity information and receivers who categorize these signals based on previous experience. We tested two hypotheses about adaptations in signalers and receivers that enable the evolution of social recognition using two species of closely related territorial poison frogs. Male golden rocket frogs (Anomaloglossus beebei) recognize the advertisement calls of conspecific territory neighbors and display a "dear enemy effect" by responding less aggressively to neighbors than strangers, while male Kai rocket frogs (A. kaiei) do not. Our results did not support the identity signaling hypothesis: both species produced advertisement calls that contain similar amounts of identity information. Our results did support the identity reception hypothesis: both species exhibited habituation of aggression to playbacks simulating the arrival of a new neighbor, but only golden rocket frogs showed renewed aggression when they subsequently heard calls from a different male. These results suggest that an ancestral mechanism of plasticity in aggression common among frogs has been modified through natural selection to be specific to calls of individual males in golden rocket frogs, enabling a social recognition system.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Gabriela Zorzal ◽  
Flávio Camarota ◽  
Marcondes Dias ◽  
Diogo M. Vidal ◽  
Eraldo Lima ◽  
...  

AbstractTerritoriality is costly, and the accurate identification of intruders and the decision to perform aggressive responses are key behavioral traits in social animals. We studied aggression among individuals belonging to close and distant nests of the plant-ant Azteca muelleri, which lives in stems of the pioneer tree Cecropia glaziovii. More specifically, we aim to investigate if the DE (dear-enemy effect—less aggression towards neighbors than strangers) or NN (nasty-neighbor effect—less aggression to strangers than neighbors) effects or even none of them apply for this iconic Azteca-Cecropia system. We further checked if ant aggression towards conspecifics is related to cuticular hydrocarbon profiles (CHCs), which provide chemical cues for nestmate recognition. Therefore, we sampled 46 nests of A. muelleri in three Brazilian Atlantic forest fragments and performed behavioral trials within and between sites. Consistently with the DE effect, we found higher aggression levels in ‘between sites’ versus ‘within sites’ treatments as well as a positive effect of spatial distance on ant aggressiveness. We found no effect of the overall dissimilarities on CHC blend on ant aggressiveness, but of one CHC class, the methylated alkanes. Overall, we provide key insights on nest-mate recognition in obligatory ant-plant mutualisms.


2020 ◽  
Vol 181 ◽  
pp. 104251
Author(s):  
Jorge Vázquez ◽  
Juan A. Fargallo ◽  
Nallely Jiménez ◽  
Fernando Aguilar-Montiel ◽  
Luisa Rodríguez-Martínez

Author(s):  
James P Tumulty ◽  
Mark A Bee

Abstract Navigating social relationships frequently rests on the ability to recognize familiar individuals using phenotypic characteristics. Across diverse taxa, animals vary in their capacities for social recognition, but the ecological and social sources of selection for recognition are often unclear. In a comparative study of two closely related species of poison frogs, we identified a species difference in social recognition of territory neighbors and investigated potential sources of selection underlying this difference. In response to acoustic playbacks, male golden rocket frogs (Anomaloglossus beebei) recognized the calls of neighbors and displayed a “dear enemy effect” by responding less aggressively to neighbors’ calls than strangers’ calls. In contrast, male Kai rocket frogs (Anomaloglossus kaiei) were equally aggressive to the calls of neighbors and strangers. This species difference in behavior is associated with key differences in reproductive ecology and characteristics of territories. Golden rocket frogs defend reproductive resources in the form of bromeliads, which is expected to create a threat asymmetry between neighbors and strangers favoring decreased aggression to neighbors. In contrast, Kai rocket frogs do not defend reproductive resources. Further, compared with Kai rocket frog territories, golden rocket frog territories occur at higher densities and are defended for longer periods of time, creating a more complex social environment with more opportunities for repeated but unnecessary aggression between neighbors, which should favor the ability to recognize and exhibit less aggression toward neighbors. These results suggest that differences in reproductive ecology can drive changes in social structure that select for social recognition.


Author(s):  
Longru Jin ◽  
Jingnan Liang ◽  
Qianxi Fan ◽  
Jiangping Yu ◽  
Keping Sun ◽  
...  

Behaviour ◽  
2020 ◽  
Vol 157 (6) ◽  
pp. 559-573
Author(s):  
Kazunori Matsumoto ◽  
Yuki Okamoto ◽  
Yuka Tsurumi ◽  
Masanori Kohda

Abstract In many territorial animals, the level of aggression exhibited toward conspecifics depends on the magnitude of the threat they pose and/or their familiarity. We conducted aquarium experiments to investigate whether the territorial cichlid fish Julidochromis transcriptus has a context-dependent agonistic response to neighbouring conspecifics. The attacking rate of territory-holding males decreased against neighbour males in an adjacent aquarium over time but increased when stranger males replaced the neighbours in the same aquarium, indicating that males displayed the ‘dear enemy effect’ toward familiar neighbours. Females were not aggressive and the dear enemy effect was not apparent among them. Interestingly, territory-holding males also increased their attacking rate against neighbour males shifted to the opposite aquarium. Territory-holding males will modify their agonistic response to conspecific males according to the relative threat of their opponents in the context of the ‘correct-incorrect boundary paradigm’.


2020 ◽  
Author(s):  
James P. Tumulty ◽  
Mark A. Bee

ABSTRACTNavigating social relationships frequently rests on the ability to recognize familiar individuals using phenotypic characteristics. Across diverse taxa, animals vary in their capacities for social recognition but the ecological and social sources of selection for recognition are often unclear. In a comparative study of two closely related species of poison frogs, we identified a species difference in social recognition of territory neighbors and investigated potential sources of selection underlying this difference. In response to acoustic playbacks, male golden rocket frogs (Anomaloglossus beebei) recognized the calls of neighbors and displayed a “dear enemy effect” by responding less aggressively to neighbors’ calls than strangers’ calls. In contrast, male Kai rocket frogs (Anomaloglossus kaiei) were equally aggressive to the calls of neighbors and strangers. This species difference in behavior was associated with key differences in reproductive ecology and characteristics of territories. Golden rocket frogs defended reproductive resources in the form of bromeliads, which is expected to create a threat asymmetry between neighbors and strangers favoring decreased aggression to neighbors. In contrast, Kai rocket frogs did not defend reproductive resources. Further, compared with Kai rocket frog territories, golden rocket frog territories occurred at higher densities and were defended for longer periods of time, creating a more complex social environment with more opportunities for repeated but unnecessary aggression between neighbors, which should favor the ability to recognize and exhibit less aggression towards neighbors. These results suggest that differences in reproductive ecology can drive changes in social structure that select for social recognition.


2018 ◽  
Author(s):  
Timothy H. Parker ◽  
Marcelina Parra ◽  
Anthony Dalisio ◽  
William E. Jensen

In many songbird species, young males learn songs from neighbors and then settle nearby, thus creating neighborhoods of conformity to local vocal culture. In some species males appear to postpone song learning until after dispersal, possibly to facilitate conformity to local dialects. Despite decades of study, we still lack a consensus regarding the selective pressures driving this delayed song learning. Two common hypothetical benefits to conformity, and thus delayed song learning, are rooted in male territorial interactions; males preferentially produce local song either to avoid detection as new arrivals (deceptive mimicry) or to be more effectively recognized as conspecific territory holders. The dickcissel (Spiza americana) is an ideal species in which to study these hypotheses. Males of this species appear to delay song learning until they arrive at their first adult territory, each individual sings a single song type, and conformity to the local song culture is high. Using playback, we contradicted both of the territorial hypotheses described above; male dickcissels did not respond differentially to local vs foreign song playback treatment. We are confident in this lack of difference because dickcissels clearly responded less strongly to a third treatment, neighbor song, than to the other two treatments, demonstrating sufficient power in our experimental design (and providing the first evidence of the dear-enemy effect in dickcissels). Our results raise the question of why dickcissels respond equally aggressively to both local and foreign songs when other bird species often show reduced aggression towards foreign song. If reduced aggression to foreign song is not ubiquitous in species that achieve conformity through delayed learning then selection from among-male territorial interaction seems unlikely to be a general explanation for such delayed learning. Reduced aggression in response to foreign songs in other species may be due to reduced exposure to the stimulus of foreign song or to different cost-benefit trade-offs when responding to songs that deviate from the local average.


Sign in / Sign up

Export Citation Format

Share Document