scholarly journals Exceptional body sizes but typical trophic structure in a Pleistocene food web

2016 ◽  
Vol 12 (5) ◽  
pp. 20160228 ◽  
Author(s):  
Angel M. Segura ◽  
Richard A. Fariña ◽  
Matías Arim
Keyword(s):  
Body Size ◽  
Trophic Position ◽  
Negative Relationship ◽  
Additional Energy ◽  
Quaternary Period ◽  
Species Vulnerability ◽  
Body Sizes ◽  
Energetic Constraints ◽  
The Relationship

In this study, we focused on the exceptionally large mammals inhabiting the Americas during the Quaternary period and the paramount role of body size in species ecology. We evaluated two main features of Pleistocene food webs: the relationship between body size and (i) trophic position and (ii) vulnerability to predation. Despite the large range of species sizes, we found a hump-shaped relationship between trophic position and body size. We also found a negative trend in species vulnerability similar to that observed in modern faunas. The largest species lived near the boundary of energetic constraints, such that any shift in resource availability could drive these species to extinction. Our results reinforce several features of megafauna ecology: (i) the negative relationship between trophic position and body size implies that large-sized species were particularly vulnerable to changes in energetic support; (ii) living close to energetic imbalance could favour the incorporation of additional energy sources, for example, a transition from a herbivorous to a scavenging diet in the largest species (e.g. Megatherium ) and (iii) the interactions and structure of Quaternary megafauna communities were shaped by similar forces to those shaping modern fauna communities.

scholarly journals Rapid Anthropocene realignment of allometric scaling rules

2020 ◽  
Author(s):  
Luca Santini ◽  
Nick J.B. Isaac
Keyword(s):  
Global Change ◽  
Population Density ◽  
Allometric Scaling ◽  
Negative Relationship ◽  
Change Scenario ◽  
Anthropogenic Pressures ◽  
Size Dependent ◽  
Energetic Constraints ◽  
The Relationship

AbstractThe negative relationship between body size and population density (SDR) in mammals is often interpreted as resulting from energetic constraints. In a global change scenario, however, this relationship might be expected to change, given the size-dependent nature of anthropogenic pressures and vulnerability to extinction. Here we test whether the SDR in mammals has changed over the last 50 years. We show that the relationship has shifted down and became shallower, corresponding to a decline in population density of 32-72%, for the largest and smallest mammals, respectively. However, the SDRs become steeper in some groups (e.g. carnivores) and shallower in others (e.g. herbivores). The Anthropocene reorganization of biotic systems is apparent in macroecological relationships that were previously believed to be immutable, reinforcing the notion that biodiversity pattens are contingent upon conditions at the time of investigation. We call for an increased attention on the role of global change on macroecological inferences.

scholarly journals Bisexual stereotypes apply differently by body size: An assessment of bisexual prototypicality, trait application, and body size

2021 ◽  
Author(s):  
Flora Oswald ◽  
Amanda champion ◽  
Devinder Singh Khera ◽  
Cory Pedersen
Keyword(s):  
Body Size ◽  
Person Perception ◽  
Online Survey ◽  
Bisexual Men ◽  
Bisexual Women ◽  
Body Sizes ◽  
And Bisexual ◽  
Fat Bodies ◽  
The Relationship

We blend person perception work with queer appearance psychology to examine the relationship between body size and bisexuality. In an online survey (N= 472, Mage= 25.15, 63.8% women), we examined the specific traits associated with a range of computer-modelled bodies identified as bisexual. We found that average body sizes were perceived as most prototypical of both bisexual men and bisexual women, skinny and fat bodies were more associated with clusters of traits which contrast with common stereotypes about bisexuality. Additionally, we found that bisexual men were associated with increased masculinity and decreased femininity relative to bisexual women, and found a general, though nonsignificant trend such that bisexual men were perceived as having heightened androcentric desire relative to women. Finally, we found evidence for the role of typicality as a mediator of perceived prejudice; less prototypical bodies tended to be perceived as experiencing greater prejudice based on body size.

The Teacher Behavior Checklist: The Mediation Role of Teacher Behaviors in the Relationship Between the Students’ Importance of Teacher Behaviors and Students’ Effort

2020 ◽  
pp. 009862832097989
Author(s):  
Michael T. Geier
Keyword(s):  
Critical Thinking ◽  
Negative Relationship ◽  
Teacher Behavior ◽  
Teacher Behaviors ◽  
Stepwise Multiple Linear Regression ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
The Relationship ◽  
Teaching Implications

Background: Previous research suggests a relationship between teacher behaviors and students’ effort. However, it is not clear what role the students’ expectations (i.e., importance of teacher behaviors) play in this relationship. Objective: Utilizing the teacher behavior checklist, this study sought to investigate whether teacher behaviors mediate the relationship between the importance students set on teacher behaviors and students’ effort. Further, the study explored which specific behaviors influence students’ effort. Method: Cross-sectional survey data were analyzed ( N = 159) using mediation analysis and stepwise multiple linear regression. Results: There was evidence that teacher behaviors mediate the relationship between the importance students set on teacher behaviors and students’ effort. Four of the 28 teacher behaviors had a significant relationship to students’ effort: creative and interesting, enthusiastic about teaching, happy/positive/humorous, and promotes critical thinking. Conclusion: Knowing students’ expectations (i.e., the importance of teacher behaviors) is essential to increasing students’ effort. Teaching Implications: Happy/positive/humorous had a negative relationship with students’ effort, while creative and interesting, enthusiastic about teaching, and promotes critical thinking showed a positive relationship with students’ effort.

scholarly journals Leader–Follower Congruence in Work Engagement and Leader–Member Exchange: The Moderating Role of Conscientiousness of Followers

2021 ◽  
Vol 12 ◽  
Author(s):  
Yanhua Ye ◽  
Ziwen Wang ◽  
Xiaowei Lu
Keyword(s):  
Work Engagement ◽  
Negative Relationship ◽  
Leader Member Exchange ◽  
Future Directions ◽  
Lmx Theory ◽  
Person Environment Fit ◽  
Work Tasks ◽  
Member Exchange ◽  
The Relationship

Extant research has investigated the relationship between work engagement and various outcomes, such as job performance and organizational commitment, neglecting the effect of work engagement on social relationships at work. Drawing upon person-environment fit theory and LMX theory, the present study aims to examine the effect of (in)congruence between leader and follower work engagement on leader–member exchange (LMX) and the moderating effect of conscientiousness. About 273 employees and 72 leaders participated in this study and completed the measurements of work engagement, conscientiousness, and LMX at two time points. Using cross-level polynomial regressions, we found that, compared with incongruent work engagement, employees perceived high levels of LMX quality when their work engagement was aligned with that of their leaders. Regarding the congruence, the employees reported higher levels of LMX when congruence in work engagement was at higher rather than lower levels. Regarding the incongruence, when the employees engaged less in their work tasks than their leaders, they were more likely to experience lower LMX. Moreover, the negative relationship between incongruence in leader and follower work engagement and LMX was mitigated when followers were more conscientious. All our hypotheses were supported. Both theoretical and practical implications for work engagement as well as future directions are discussed.

Close social relationships and loneliness: the role of subjective age

2019 ◽  
pp. 1-5 ◽  
Author(s):  
Naama Spitzer ◽  
Dikla Segel-Karpas ◽  
Yuval Palgi
Keyword(s):  
Older Adults ◽  
Social Relationships ◽  
Negative Relationship ◽  
Community Dwelling ◽  
Subjective Age ◽  
Perceptions Of Aging ◽  
The Relationship ◽  
Moderating Role

Abstract Loneliness is considered a major issue, often negatively influencing the quality of life of individuals of all ages, and of older adults, in particular. The aims of this study are: (1) to assess the association between close social relationships and loneliness; and (2) to examine the moderating role of subjective age in this association. Married or cohabiting community-dwelling Israelis in the second half of life (N = 360) were interviewed and reported on their close social relationships, their level of loneliness, and their subjective age. The number of close social relationships was found to have a negative relationship with loneliness. Moreover, subjective age was found to moderate the relationship between close social relationships and loneliness, such that the association was weaker for those with older subjective age. Those with older subjective age are often not able to benefit from close social relationships to alleviate loneliness as much as their younger-subjective-age counterparts. Efforts to address older adults’ loneliness should consider focusing on older adults’ perceptions of aging.

scholarly journals In Pursuit of Work Performance: Testing the Contribution of Emotional Intelligence and Burnout

2020 ◽  
Vol 17 (15) ◽  
pp. 5373
Author(s):  
Martin Sanchez-Gomez ◽  
Edgar Breso
Keyword(s):  
Emotional Intelligence ◽  
Work Performance ◽  
Negative Relationship ◽  
Performance Testing ◽  
Maslach Burnout Inventory ◽  
Multiple Mediation ◽  
Mediation Analyses ◽  
The Individual ◽  
The Relationship

Previous research has highlighted the connection between emotional intelligence (EI) and work performance. However, the role of job burnout in this context remains relatively unexplored. This study aimed to examine the mediator role of burnout in the relationship between EI and work performance in a multioccupational sample of 1197 Spanish professionals (58.6% women). The participants completed the Wong and Law Emotional Intelligence Scale, the Maslach Burnout Inventory, and the Individual Work Performance Questionnaire. As expected, the results demonstrated a positive relationship between EI and performance, and a negative relationship with burnout, which has a mediator effect in the relationship between EI and work performance. Professionals with high levels of IE and low burnout reported the highest performance. Multiple mediation analyses showed that employees’ EI was indirectly connected to work performance via professional efficacy and exhaustion, even when controlling the effects of sociodemographic variables. The same pattern was found when multiple mediations were conducted for each EI dimension. These findings demonstrate the importance of burnout in understanding work performance and emphasize the role of EI as a protective variable which can prevent the development or chronic progression of workers’ burnout.

Experiencing workplace ostracism with loss of engagement

2020 ◽  
Vol 35 (7/8) ◽  
pp. 617-630
Author(s):  
Xiaofeng Xu ◽  
Ho Kwong Kwan ◽  
Miaomiao Li
Keyword(s):  
Social Exchange ◽  
Social Exchange Theory ◽  
Negative Relationship ◽  
Job Engagement ◽  
Cultural Perspective ◽  
Content Type ◽  
Mediating Role ◽  
Workplace Ostracism ◽  
The Relationship

PurposeDrawing on social exchange theory and a cultural perspective, this study examines the relationship between workplace ostracism and job engagement by focusing on the mediating role of felt obligation and the moderating role of collectivism.Design/methodology/approachA two-wave survey was conducted over four months in a private service business in China. The participants comprised 108 Chinese employees.FindingsThe results indicate that workplace ostracism has a negative relationship with job engagement through a reduced sense of felt obligation. Collectivism strengthens the main effect of workplace ostracism on felt obligation and its indirect effect on job engagement via felt obligation.Research limitations/implicationsThis study contributes to understanding of the internal mechanism of the workplace ostracism–job engagement model by identifying the mediating role of felt obligation. It also emphasizes that collectivist cultures can enhance the effects of workplace ostracism. However, the generalizability of our findings may be limited due to this cultural factor.Practical implicationsOur findings show that workplace ostracism plays a significant role in reducing job engagement. Therefore, it is essential to reduce the incidence of ostracism in the workplace.Originality/valueBy addressing the previously unexplored mechanism that mediates the relationship between workplace ostracism and job engagement, this study provides new directions for research on workplace ostracism and job engagement.

Moderating role of employee engagement on conflict–politics relationship

2019 ◽  
Vol 26 (6) ◽  
pp. 1781-1798 ◽  
Author(s):  
Poonam Mishra ◽  
Amitabh Deo Kodwani
Keyword(s):  
Employee Engagement ◽  
Negative Relationship ◽  
Intention To Leave ◽  
Self Report ◽  
Relationship Conflict ◽  
Content Type ◽  
The Relationship ◽  
Moderating Role ◽  
Openness To Diversity

Purpose The purpose of this paper is to explore the relationship between relationship conflict and the perception of organization politics (POP) and the moderating role of employee engagement. The study hypothesizes that the conflict results in the presence of POP only for those employees who are relatively less engaged with the organization. The paper further explores the mediating role of perceived politics between the relationship conflict and job-related outcome variables including openness to diversity, turnover intent and perception of justice. In sum, the authors contend that employee engagement will act as a moderator between relationship conflict and POP, and POP further will act as a mediator between relationship conflict and its job-related outcomes. Design/methodology/approach A descriptive study was carried on to conduct this research. Data were collected at two different points of time from the employees of two public sector undertakings (n=206). About 80 questionnaires were not returned by the respondents, reducing the sample size to be 126. Of these, 115 were usable, resulting in a 55.83 percent response rate. SEM was employed to test the hypotheses with the help of Smart PLS 3.0. A two-step process was followed to test the hypothesized model. Testing the significance of proposed relationships in the structural model was followed by the evaluation of the measurement model. Findings The results of the study highlighted a positive association between the relationship conflict and POP. A moderating effect of employee engagement on relationship conflict and perceived organizational politics (POP) was observed. Further, POP was found to have a positive relationship with the intention to leave and a negative relationship with openness to diversity and perception of justice was observed. POP mediated the relationship between relationship conflict with the intention to leave and the perception of justice. Research limitations/implications The very first limitation of the present study is its cross-sectional design. Since the data were gathered from the same respondents, the causal relationships between variables are subject to biases (Bobko and Stone-Romero, 1998). Further, the data were gathered with the help of self-report questionnaires, and the findings of this study might have been influenced by the social desirability response bias (Podsakoff et al., 2003). Hence, future work should focus on using a combination of sources for data collection. This study also proposes a possible role of emotional intelligence in employee engagement and their POP, which can be tested in future studies. Practical implications The study suggests that relationship conflict leads to POP, which eventually results in adverse job-related outcomes. In order to control the negative effects of politics perception, organizations should undertake conflict prevention and conflict management techniques. To further reduce the level of POP, organizations shall take steps to better engage their employees because even when the level of relationship conflict is high, people perceive less politics if they are highly engaged with the organization. Originality/value The study is an original work carried out to understand the relationship between relationship conflict and the POP, and the moderating role of employee engagement.

scholarly journals Body size is negatively correlated with trophic position among cyprinids

2016 ◽  
Vol 3 (5) ◽  
pp. 150652 ◽  
Author(s):  
Edward D. Burress ◽  
Jordan M. Holcomb ◽  
Karine Orlandi Bonato ◽  
Jonathan W. Armbruster
Keyword(s):  
Body Size ◽  
Trophic Position ◽  
Isotope Analysis ◽  
Negative Relationship ◽  
Species Traits ◽  
Food Web Structure ◽  
Mechanical Constraints ◽  
Web Structure ◽  
Significant Negative Relationship ◽  
Multiple Levels

Body size has many ecological and evolutionary implications that extend across multiple levels of organization. Body size is often positively correlated with species traits such as metabolism, prey size and trophic position (TP) due to physiological and mechanical constraints. We used stable isotope analysis to quantify TP among minnows across multiple assemblages that differed in their species composition, diversity and food web structure. Body size significantly predicted TP across different lineages and assemblages, and indicated a significant negative relationship. The observed negative relationship between body size and TP is contrary to conventional knowledge, and is likely to have arisen owing to highly clade-specific patterns, such that clades consist of either large benthic species or small pelagic species. Cyprinids probably subvert the physiological and mechanical constraints that generally produce a positive relationship between body size and TP using anatomical modifications and by consuming small-bodied prey, respectively. The need for herbivorous cyprinids to digest cellulose-rich foods probably selected for larger bodies to accommodate longer intestinal tracts and thereby to facilitate digestion of nutrient-poor resources, such as algae. Therefore, body size and TP are likely to have coevolved in cyprinids in association with specialization along the benthic to pelagic resource axis.

scholarly journals Ketidakamanan pekerjaan dan kinerja tugas: Peran burnout sebagai mediator

2021 ◽  
Vol 9 (2) ◽  
pp. 150-155
Author(s):  
Alice Salendu ◽  
Muhamad Fachri Maldini
Keyword(s):  
Task Performance ◽  
Work Experience ◽  
Job Insecurity ◽  
Negative Relationship ◽  
Maslach Burnout Inventory ◽  
Mediating Effect ◽  
Design Data ◽  
The Relationship ◽  
And Task

An increasingly dynamic and uncertain job demands provided new challenges for employees in task performance, had an impact on job insecurity, and triggered burnout for employees. This study investigated the predictor role of job insecurity on task performance through the mediation role of burnout. The researcher conducted correlational research with a non-experimental research design. Data were collected from 106 respondents who were private employees with a minimum of one year of work experience. The sampling technique used was convenience sampling. This study was conducted by using the Job Insecurity Scale, Task Performance Scale, and Maslach Burnout Inventory - General Scale which was adapted in Indonesia language. The data were processed using multiple regression analysis with mediating variables. The result of this research showed that job insecurity had a negative relationship with task performance (b = −0.35, t = −2.78; p = 0.00). In addition, it was also found that burnout partially mediated the relationship between job insecurity and task performance (β = -0.20, SE =0.07; 99% CI [-0.41,-0.05]). There was evidence that job insecurity had a negative relationship with task performance and burnout had a mediating effect on the relationship between job insecurity and task performance.

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