scholarly journals Social consequences of energetically costly nest construction in a facultatively social bee

2021 ◽  
Vol 288 (1949) ◽  
Author(s):  
Madeleine M. Ostwald ◽  
Trevor P. Fox ◽  
Jon F. Harrison ◽  
Jennifer H. Fewell
Keyword(s):  
Social Groups ◽  
Group Living ◽  
Social Consequences ◽  
Nest Construction ◽  
Construction Costs ◽  
Carpenter Bee ◽  
Nest Founding ◽  
Prohibitive Cost ◽  
Nest Quality ◽  
Social Bee

Social groups form when the costs of breeding independently exceed fitness costs imposed by group living. The costs of independent breeding can often be energetic, especially for animals performing expensive behaviours, such as nest construction. To test the hypothesis that nesting costs can drive sociality by disincentivizing independent nest founding, we measured the energetics of nest construction and inheritance in a facultatively social carpenter bee ( Xylocopa sonorina Smith), which bores tunnel nests in wood. We measured metabolic rates of bees excavating wood and used computerized tomography images of nesting logs to measure excavation volumes. From these data, we demonstrate costly energetic investments in nest excavation of a minimum 4.3 kJ per offspring provisioned, an expense equivalent to nearly 7 h of flight. This high, potentially prohibitive cost of nest founding may explain why females compete for existing nests rather than constructing new ones, often leading to the formation of social groups. Further, we found that nest inheritors varied considerably in their investment in nest renovation, with costs ranging more than 12-fold (from 7.08 to 89.1 kJ energy), probably reflecting differences in inherited nest quality. On average, renovation costs were lower than estimated new nest construction costs, with some nests providing major savings. These results suggest that females may join social groups to avoid steep energetic costs, but that the benefits of this strategy are not experienced equally.

scholarly journals Fluid Nest Membership Drives Variable Relatedness in Groups of a Facultatively Social Bee

2021 ◽  
Vol 9 ◽  
Author(s):  
Madeleine M. Ostwald ◽  
Romain A. Dahan ◽  
Zachary Shaffer ◽  
Jennifer H. Fewell
Keyword(s):  
Group Composition ◽  
Group Formation ◽  
Group Living ◽  
Migration Behavior ◽  
Ecological Constraints ◽  
Carpenter Bee ◽  
Indirect Fitness ◽  
Fitness Benefits ◽  
Nesting Aggregation ◽  
Social Bee

Kin selection theory has dominated our understanding of the evolution of group living. However, many animal groups form among non-relatives, which gain no indirect fitness benefits from cooperating with nestmates. In this study, we characterized the relatedness and inter-nest migration behavior of the facultatively social carpenter bee, Xylocopa sonorina. Nesting constraints due to costly nest construction in this species give rise to intense intraspecific competition over access to existing nests. We used mark-recapture techniques to characterize patterns of dispersal and nest relocation within a nesting aggregation of spatially clustered nests. Two-thirds of bees relocated at least once during the reproductive season, likely to seek reproductive opportunities in another nest. This fluid nest membership creates opportunities for association among non-relatives. To assess the effects of this dynamic nesting behavior on group relatedness, we used microsatellite analysis to estimate relative relatedness within and between nests in the aggregation. We found that relatedness was variable across sampling years, but that in many cases nestmates were no more related to one another than they were to non-nestmate bees in the population. Together, these results suggest that group composition in X. sonorina may result from strategies to maximize direct fitness. This study supports the hypothesis that factors beyond kinship, such as ecological constraints, are likely to drive group formation in this species.

Peak occurrence of female sexual initiation predicts day of conception in rhesus monkeys (Macaca mulatta)

2000 ◽  
Vol 12 (8) ◽  
pp. 397 ◽  
Author(s):  
Julia L. Zehr ◽  
Pamela L. Tannenbaum ◽  
Benjamin Jones ◽  
Kim Wallen
Keyword(s):  
Rhesus Monkeys ◽  
Social Groups ◽  
Group Living ◽  
Sexual Initiation ◽  
Adult Males ◽  
Non Invasive ◽  
Sexual Solicitation ◽  
Delivery Date ◽  
Conception Date ◽  
Highly Correlated

The present study investigated whether peaks in female sexual initiation could accurately predict conception in group-living female rhesus monkeys. Behavioral observations, 4 or 5 days per week in large, stable, social groups of monkeys, provided frequencies of female initiation of proximity, sexual solicitation, mounts, and ejaculations. Since a preovulatory peak in female sexual initiation is likely linked to the preovulatory oestradiol surge, we used the third day after a peak in behavior as the behavioral estimate of conception date. For each pregnancy, an independent estimate of conception date was derived from ultrasound determination of fetal length. Estimates of conception based on female initiation of proximity with adult males were accurate for more than 90% of pregnancies, whereas observation of ejaculations by males predicted conception in fewer than 60% of pregnancies. Behavioral and ultrasound estimates of conception date were highly correlated and differed by less than 1 day on average. Accordingly, predictions of delivery date based on behavioral estimates of conception date were as accurate as those based on ultrasound-derived estimates. These data suggest that female-initiated sexual behavior can be used in rhesus monkeys as a practical, non-invasive tool for producing timed matings in social groups of monkeys, providing accurate estimates of conception date, gestational age, and predicted date of birth.

scholarly journals The Development and Consequences of Moral Essentialism

2020 ◽  
Author(s):  
Larisa Heiphetz
Keyword(s):  
Natural Kinds ◽  
Social Groups ◽  
Social Consequences ◽  
The Body ◽  
Moral Judgments ◽  
Psychological Characteristics ◽  
Legal Domain ◽  
Pro Social Behavior ◽  
Weakened Form ◽  
Over Time

Children report that many natural kinds, social groups, and psychological characteristics arise from an innate, internal “essence” that is rooted in biology and remains stable over time. These perceptions persist into adulthood, albeit often in weakened form. This paper argues that in addition to the domains previously examined in the essentialism literature, children—and to some extent adults—also view moral characteristics in essentialist terms. This form of essentialism has important social consequences, including in the area of pro-social behavior and in the legal domain. The body of evidence reviewed here suggests that children’s and adults’ moral judgments depend not just on what people do but also on perceptions of who those people are, i.e., whether they are people of good or bad moral character.

scholarly journals Social consequences of COVID-19 conspiracy beliefs: Evidence from two studies in Slovakia

2021 ◽  
Author(s):  
Jakub Šrol ◽  
Vladimira Cavojova ◽  
Eva Ballová Mikušková
Keyword(s):  
Social Groups ◽  
Distinct Pattern ◽  
Social Consequences ◽  
Wide Spread ◽  
Government Regulations ◽  
Conspiracy Theories ◽  
Lack Of Control ◽  
Conspiracy Beliefs ◽  
Prejudice And Discrimination ◽  
Negative Feelings

One of the appeals of conspiracy theories in times of crises, such as the COVID-19 pandemic, is that they provide a scapegoat – someone to blame for what has happened. By doing this, they increase distrust, negative feelings, and even hostility toward implicated actors, whether those are powerful social outgroups or one’s own government representatives. We report two studies to examine such social consequences of COVID-19 conspiracy theories. In Study 1 (N = 501), we showed the distinct pattern of relationships between China-specific and generic COVID-19 conspiracy beliefs and prejudice and discrimination toward three social groups associated with the pandemic. In Study 2 (N = 1024), lowered trust in government regulations and increased hostility associated with the COVID-19 and generic conspiracy beliefs predicted justification of and willingness to engage in non-compliance with government regulations, violent attacks on 5G masts, and anti-government protests. Also, across both studies, increased exposure to information about COVID-19 was associated with endorsing fewer conspiracy theories, but it also brought about stronger feelings of anxiety and lack of control, which in turn contributed to higher conspiracy belief. We highlight the potential social problems associated with the wide-spread COVID-19 conspiracy theories as well as potential solutions to counteract them.

scholarly journals The Infertility Trap: The Fertility Costs of Group-Living in Mammalian Social Evolution

2021 ◽  
Vol 9 ◽  
Author(s):  
Robin I. M. Dunbar ◽  
Susanne Shultz
Keyword(s):  
Group Size ◽  
Social Evolution ◽  
Low Cost ◽  
Social Groups ◽  
Group Living ◽  
The Other ◽  
Risk Averse ◽  
Limit Group ◽  
Grouping Patterns ◽  
Environmental Demands

Mammal social groups vary considerably in size from single individuals to very large herds. In some taxa, these groups are extremely stable, with at least some individuals being members of the same group throughout their lives; in other taxa, groups are unstable, with membership changing by the day. We argue that this variability in grouping patterns reflects a tradeoff between group size as a solution to environmental demands and the costs created by stress-induced infertility (creating an infertility trap). These costs are so steep that, all else equal, they will limit group size in mammals to ∼15 individuals. A species will only be able to live in larger groups if it evolves strategies that mitigate these costs. We suggest that mammals have opted for one of two solutions. One option (fission-fusion herding) is low cost but high risk; the other (bonded social groups) is risk-averse, but costly in terms of cognitive requirements.

scholarly journals An intraspecific appraisal of the social intelligence hypothesis

2018 ◽  
Vol 373 (1756) ◽  
pp. 20170288 ◽  
Author(s):  
Benjamin J. Ashton ◽  
Alex Thornton ◽  
Amanda R. Ridley
Keyword(s):  
Cognitive Abilities ◽  
Social Intelligence ◽  
Social Groups ◽  
Group Living ◽  
Cognitive Evolution ◽  
Theme Issue ◽  
Social Intelligence Hypothesis ◽  
Developmental Factors ◽  
Cognitive Research ◽  
The Social

The prevailing hypotheses for the evolution of cognition focus on either the demands associated with group living (the social intelligence hypothesis (SIH)) or ecological challenges such as finding food. Comparative studies testing these hypotheses have generated highly conflicting results; consequently, our understanding of the drivers of cognitive evolution remains limited. To understand how selection shapes cognition, research must incorporate an intraspecific approach, focusing on the causes and consequences of individual variation in cognition. Here, we review the findings of recent intraspecific cognitive research to investigate the predictions of the SIH. Extensive evidence from our own research on Australian magpies ( Cracticus tibicen dorsalis ), and a number of other taxa, suggests that individuals in larger social groups exhibit elevated cognitive performance and, in some cases, elevated reproductive fitness. Not only do these findings demonstrate how the social environment has the potential to shape cognitive evolution, but crucially, they demonstrate the importance of considering both genetic and developmental factors when attempting to explain the causes of cognitive variation. This article is part of the theme issue ‘Causes and consequences of individual differences in cognitive abilities’.

scholarly journals Unreciprocated allogrooming hierarchies in a population of wild group-living mammals

2021 ◽  
Author(s):  
Catherine E Nadin ◽  
David W. Macdonald ◽  
Sandra Baker ◽  
Christina D. Buesching ◽  
Stephen Ellwood ◽  
...  
Keyword(s):  
Social Structure ◽  
Social Status ◽  
Dominance Rank ◽  
Social Groups ◽  
Group Living ◽  
Meles Meles ◽  
Social Species ◽  
Novel Approach ◽  
European Badgers ◽  
Wild Group

Allogrooming can relate to social status in mammalian societies, and thus, be used to infer social structure. This relationship has previously been investigated by examining an individual’s dominance rank and their total amount of allogrooming. This, however, does not account for the identity of allogrooming partners. We applied a novel approach, calculating the linearity and steepness of unreciprocated allogrooming hierarchies using actor–receiver matrices in European badgers (Meles meles) groups. Badgers have relatively unstructured social groups compared to most group-living carnivores and allogrooming in badgers is currently hypothesized to have a hygiene function. We examine whether allogrooming is linked to social status by investigating: 1) the presence, linearity, and steepness of unreciprocated allogrooming hierarchies; 2) the trading of unreciprocated allogrooming for the potential benefit of receiving reduced aggression from dominant individuals; and, 3) whether unreciprocated allogrooming is associated with relatedness. We found weak unreciprocated allogrooming hierarchies, with marginal linearity, steepness overall, and variation between social-group-years. Unreciprocated allogrooming was positively correlated with directed aggression, potentially providing evidence for the trading of allogrooming for reduced aggression. Allogrooming was not correlated with relatedness, possibly due to high relatedness within social groups. Our findings reaffirm that European badgers have a relatively unstructured social system; likely reflecting a relatively simple state of sociality in Carnivores, with little need for hierarchical order. Using actor–receiver unreciprocated allogrooming matrices to test for linearity and steepness of unreciprocated allogrooming hierarchies in other social species will improve knowledge of group social structure.

scholarly journals Role of sociality in the response of killer whales to an additive mortality event

2019 ◽  
pp. 201817174 ◽  
Author(s):  
Marine Busson ◽  
Matthieu Authier ◽  
Christophe Barbraud ◽  
Paul Tixier ◽  
Ryan R. Reisinger ◽  
...  
Keyword(s):  
Social Structure ◽  
Social Groups ◽  
Group Living ◽  
Foraging Success ◽  
Killer Whales ◽  
Negative Effects ◽  
Mortality Event ◽  
Individual Fitness ◽  
Fishing Vessels ◽  
Additive Mortality

In highly social top predators, group living is an ecological strategy that enhances individual fitness, primarily through increased foraging success. Additive mortality events across multiple social groups in populations may affect the social structure, and therefore the fitness, of surviving individuals. This hypothesis was examined in a killer whale (Orcinus orca) population that experienced a 7-y period of severe additive mortality due to lethal interactions with illegal fishing vessels. Using both social and demographic analyses conducted on a unique long-term dataset encompassing periods before, during, and after this event, results indicated a decrease in both the number and the mean strength of associations of surviving individuals during the additive mortality period. A positive significant correlation between association strength and apparent survival suggested that the fitness of surviving individuals was impacted by the additive mortality event. After this event, individuals responded to the loss of relatives in their social groups by associating with a greater number of other social groups, likely to maintain a functional group size that maximized their foraging success. However, these associations were loose; individuals did not reassociate in highly stable social groups, and their survival remained low years after the mortality event. These findings demonstrate how the disruption of social structure in killer whales may lead to prolonged negative effects of demographic stress beyond an additive mortality event. More importantly, this study shows that sociality has a key role in the resilience of populations to human-induced mortality; this has major implications for the conservation of highly social and long-lived species.

scholarly journals Choice or opportunity: are post-release social groupings influenced by familiarity or reintroduction protocols?

Oryx ◽  
2018 ◽  
Vol 54 (2) ◽  
pp. 215-221 ◽  
Author(s):  
K. E. Moseby ◽  
D. T. Blumstein ◽  
M. Letnic ◽  
R. West
Keyword(s):  
Health Outcomes ◽  
Social Cohesion ◽  
Social Groups ◽  
Group Living ◽  
Release Area ◽  
Reintroduction Success

AbstractThe conservation benefits of maintaining social groupings during and after animal translocations are unclear. Although some studies report improved post-release survival, others found no discernible influence on reintroduction success. Understanding the effects of social groupings is difficult because release methods can influence the animals’ ability to maintain social groups. We explored this relationship by first studying whether release protocols influenced post-release cohesion in the communal burrowing bettong Bettongia lesueur, and then investigating whether maintenance of social cohesion conferred any post-release advantage. We released bettongs into a small (8 ha) and large (2,600 ha) area and compared the proportion that maintained social groupings in the different settings. The proportion of bettongs sharing with previous warren co-occupants was higher than expected by chance in both areas, however, a significantly higher proportion of bettongs maintained social groupings in the small (75%) compared to the large release area (13%). This suggests bettongs prefer to maintain social groupings but are unable to locate members of their group in large release areas. Bettongs that did maintain social groupings showed no difference in reproductive or health outcomes compared to those that formed new social groupings, suggesting no benefit to reintroduction success. We conclude that release protocols can influence post-release cohesion, but that greater cohesion does not necessarily confer advantages to group-living animals. To test the importance of social cohesion, further research on reintroductions should compare post-release parameters for animals released using protocols that do and do not facilitate maintenance of social groupings.

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