Social Interactions in Two Sympatric Salamanders: Effectiveness of a Highly Aggressive Strategy

Behaviour ◽  
1997 ◽  
Vol 134 (1-2) ◽  
pp. 71-88 ◽  
Author(s):  
Carl D. Anthony ◽  
Robert G. Jaeger ◽  
Jill A. Wicknick

AbstractIn terrestrial plethodontid salamanders, aggressive behaviour is thought to function in the spacing of territorial residents among contested cover objects on the forest floor. Such behaviour, when exhibited toward heterospecifics, plays an important role in the competitive interactions between species. We compared levels of aggressive behaviour in intra- and interspecific contexts in two species of sympatric salamanders (Plethodon ouachitae and P. albagula) that have similar ecological requirements but differ in adult size. We also tested the effectiveness of such behaviour in holding cover objects (territorial foci) in the laboratory and on the forest floor. We predicted that if one species were more aggressive than the other, then that species would have greater success in obtaining and holding cover objects. In laboratory trials, residents of P. ouachitae (the smaller species) were extremely aggressive in both intra- and interspecific contexts. Individuals of P ouachitae delivered bites at a rate 14 times that of previously studied species of Plethodon and were significantly more likely to escalate to biting when tested as territorial residents (in intra- and interspecific trials) and as intruders (in interspecific trials). Plethodon albagula exhibited a lower level of aggression, similar to other species of Plethodon. In laboratory trials, in which salamanders competed for cover objects of differing quality, residents of P. ouachitae were effective in expelling conspecific intruders, and they were marginally effective at expelling intruding P. albagula. Residents of P. albagula were less effective in expelling conspecific intruders and did not expel intruding P. ouachitae. We conclude that the extreme aggression exhibited by P. ouachitae enabled it to expel intruders from artificial cover objects and to invade cover objects held by larger heterospecific residents. Field data supported intraspecific defence of cover objects by P. ouachitae, but results for P. albagula were inconclusive. These results are consistent with the geographic distributions of these species (P. ouachitae typically outnumbers P. albagula in the Ouachita Mountains) and provide an example of a behavioural mechanism overcoming a size-related disadvantage.

2014 ◽  
Vol 14 (2) ◽  
pp. 365-375 ◽  
Author(s):  
Marcin T. Górecki ◽  
Natalia Dziwińska

Abstract The aim of this study was to recognize features determining social hierarchy in Wrzosówka Polska ewes kept indoors as well as to investigate their resting place and companionship preferences. Observations (156 hours in total) were carried out in a group of 22 ewes. The social rank of sheep was determined by their age, body weight and length of horns. Social position was positively correlated with aggressive behaviour performed and negatively with aggressive behaviour received. Use of space while resting was influenced by ewe social behaviour; aggressive individuals lied more often in attractive places, namely against walls and fodder troughs compared to other animals. In general, the ewes rested by having physical contact with animals of similar rank and aggressiveness. Kinship appeared not to be important in neighbour preference. As can be concluded, social interactions influenced the use of space and neighbourhood in ewes


2020 ◽  
Author(s):  
Svenja Taubner ◽  
Sophie Hauschild ◽  
Lea Korhas ◽  
Michael Kaess ◽  
Esther Sobanski ◽  
...  

Abstract Background: Conduct disorder (CD) is a complex mental disorder characterized by severe rule breaking and aggressive behaviour. While studies have shown that several therapeutic interventions are effective in treating CD symptoms, researchers call for treatments based on etiological knowledge and potential patho-mechanisms. Mentalization-based treatment (MBT) may represent such a treatment approach: Studies have shown that individuals with CD show mentalizing deficits and that mentalizing might represent a protective factor against the development of the disorder. As MBT focuses on the understanding of social behaviour in terms of mental states, fostering mentalizing might help CD individuals to (re)gain an adaptive way of coping with negative emotions especially in social interactions and thus reduce aggressive behaviour. For this purpose, MBT was adapted for adolescents with CD (MBT-CD). This is a protocol of a feasibility and pilot study primarily investigating the acceptability of the intervention and the scientific assessments by CD individuals and their families based on quantitative and qualitative data as well as necessary organizational resources. Secondary aim is to investigate the course of symptom severity and mentalizing skills.Methods: The bi-centre study is carried out in two outpatient settings associated with University Hospitals (Heidelberg and Mainz) in Germany. Adolescents aged between 11 and 18 years with a CD or oppositional defiant disorder (ODD) diagnosis are included. Participants receive MBT-CD for 6 to 12 months. Primary outcome of the feasibility study (e.g. recruitment and adherence rates) will be descriptively analysed. Multilevel modelling will be used to investigate secondary outcome data.Discussion: Fostering the capacity to mentalize social interactions triggering non-mentalized, aggressive behaviour might help CD individuals to behave more adaptively. The feasibility trial is essential for gathering information on how to properly conduct MBT-CD including appropriate scientific assessments in this patient group, in order to subsequently investigate the effectiveness of MBT-CD in an RCT.


1987 ◽  
Vol 63 (5) ◽  
pp. 340-346 ◽  
Author(s):  
M. G. Weber ◽  
C. E. Van Wagner ◽  
Monte Hummel

Fire behavior variables were quantified in eastern Ontario jack pine (Pinus banksiana Lamb.) ecosystems and used to interpret observed fire impacts and effects. A series of seven fires, ranging in frontal fire intensity from 70 to 17 000 W/m, were documented. Forest floor moisture content prior to burning was negatively correlated with weight of forest floor consumed per unit area (r2 = 0.97) and per cent mineral soil bared (r2 = 0.95). Frontal fire intensity was positively correlated with per cent tree mortality (r2 = 0.98) and mean height of char (r2 = 0.76). Frontal fire intensities of 17 000 kW/m resulted in seedling numbers of 30 000 to over 50 000 ha−1 considered to be more than adequate for establishing the next generation of crop trees. Jack pine mean seedling height, 13 to 16 years after fire, was also positively correlated with frontal fire intensity (r2 = 0.82), ranging from 0.5 to 3.8 m on lowest and highest intensity burns, respectively. Similar relationships were found when seedling height was regressed against per cent tree mortality (r2 = 0.62) and forest floor consumption (r2 = 0.79).Results are discussed in terms of ecological requirements of the species, particularly during the regeneration phase, and it is concluded that quantification of fire behavior observations is mandatory if burning conditions are to be understood and/or duplicated by the land manager for the attainment of a given forest management objective.


1974 ◽  
Vol 82 (1) ◽  
pp. 147-163 ◽  
Author(s):  
D. Fraser

SUMMARYThree experiments studied the behaviour of pigs which were brought together for brief periods of observation on successive days. Two distinct patterns of aggressive behaviour were observed, one involving biting and the other involving butting. Biting was common when the pigs first met, and butting seemed to replace biting in some cases. Pairs of pigs which had no previous contact frequently showed a straight forward type of dominance with one pig performing almost all the biting and butting; among well-acquainted pairs, however, the relationships were frequently more complex.Of all the experimental manipulations, familiarity between two animals had the most profound effect on the behaviour. Biting, but not butting, was reduced if the pigs were housed in neighbouring pens, or if they had previously shared the same pen. Biting was almost eliminated, and butting was reduced, if the pigs lived together throughout the time of the observations. There were no differences between females and castrated males, or between individually-housed and group-housed animals in either type of behaviour.Pigs which were subjected to repeated biting generally became less active, refraining from some social and non-social activities. Butting did not appear to have similar effects on the recipient animals.The experiments illustrated some complex social interactions involving a large number of distinct social activities. In this light, the usefulness of such broad terms as ‘aggression’ and ‘dominance’ is discussed.


1990 ◽  
Vol 35 (4) ◽  
pp. 468 ◽  
Author(s):  
Cindy L. Taylor ◽  
Robert F. Wilkinson ◽  
Chris L. Peterson

2015 ◽  
Vol 24 (4) ◽  
pp. 544 ◽  
Author(s):  
Roger W. Perry ◽  
Virginia L. McDaniel

Some bat species, including eastern red bats (Lasiurus borealis), roost for short periods beneath leaf litter on the forest floor during winter in the south-eastern USA, a region subjected to frequent fire. The variability in fuel consumption, the heterogeneous nature of burns, and the effects of litter and duff moisture on forest-floor temperatures during winter burning could influence potential survival for bats beneath the leaf litter if they are unable to escape on-coming flames. We measured temperatures below leaf litter in 64 south-slope plots during nine controlled burns in the Ouachita Mountains of Arkansas to determine the probability of survival. Maximum temperature recorded under leaf litter at each plot averaged 292°C (±20 s.e.) and ranged from 10 to 717°C. Only three (5%) of the plots experienced temperatures that were deemed survivable (<60°C sustained for 60 s) during burns on warmer winter days (air temperatures 15.0–26.1°C). Temperatures below the leaf litter measured just before the arrival of fire (average = 19.6°C) suggested that if bats were roosting in plots they would have been in shallow torpor, which would have enabled faster escape from approaching flames. Burning during the warmer periods of winter (e.g. ≥15°C) and during afternoons could potentially improve survival by bats roosting under leaf litter by reducing arousal and escape times.


Author(s):  
Connie K. Porcaro ◽  
Clare Singer ◽  
Boris Djokic ◽  
Ali A. Danesh ◽  
Ruth Tappen ◽  
...  

Purpose Many aging individuals, even those who are healthy, report voice changes that can impact their ability to communicate as they once did. While this is commonly reported, most do not seek evaluation or management for this issue. The purpose of this study was to investigate the prevalence and differences in voice disorders in older adults, along with the effect of fatigue on their social interactions. Method This is a cross-sectional investigation of a community-dwelling sample of individuals aged 60 years or older. Participants completed the Questionnaire on Vocal Performance, the Social Engagement Index subset “Engagement in Social or Leisure Activities,” and the Fatigue Severity Scale. Results Results indicated 32.5% of the 332 participants reported symptoms of voice problems with no difference found between male and female respondents. A slight increase in report of voice problems was noted with each year of age. Participants who self-reported voice problems indicated less interaction in social activities involving communication than those who did not. Finally, as severity of self-reported voice problems increased, an increase was reported by the same individuals for signs of fatigue. Conclusions Voice problems and resulting decreased social interaction are commonly experienced by older individuals. Voice symptoms in older adults have been found to benefit from evidence-based treatment strategies. It is critical to provide education to encourage older individuals to seek appropriate evaluation and management for voice issues through a speech-language pathologist or medical professional.


2010 ◽  
Vol 19 (4) ◽  
pp. 108-114 ◽  
Author(s):  
Lisa M. Mellman ◽  
Laura S. DeThorne ◽  
Julie A. Hengst

Abstract The present qualitative study was designed to examine augmentative and alternative communication (AAC) practices, particularly surrounding speech-generating devices (SGDs), in the classroom setting. We focused on three key child participants, their classroom teachers, and associated speech-language pathologists across three different schools. In addition to semi-structured interviews of all participants, six classroom observations per child were completed. Data were coded according to both pre-established and emergent themes. Four broad themes emerged: message-focused AAC use, social interactions within the classroom community, barriers to successful AAC-SGD use, and missed opportunities. Findings revealed a lack of SGD use in the classroom for two children as well as limited social interaction across all cases. We conclude by highlighting the pervasive sense of missed opportunities across these classroom observations and yet, at the same time, the striking resiliency of communicative effort in these cases.


Sign in / Sign up

Export Citation Format

Share Document