Search results for "Labour"
showing 10 items of 655 documents
Ecology and Evolution of Communication in Social Insects
2016
Insect life strategies comprise all levels of sociality from solitary to eusocial, in which individuals form persistent groups and divide labor. With increasing social complexity, the need to communicate a greater diversity of messages arose to coordinate division of labor, group cohesion, and concerted actions. Here we summarize the knowledge on prominent messages in social insects that inform about reproduction, group membership, resource locations, and threats and discuss potential evolutionary trajectories of each message in the context of social complexity.
Life history evolution in social insects: a female perspective
2016
Social insects are known for their unusual life histories with fecund, long-lived queens and sterile, short-lived workers. We review ultimate factors underlying variation in life history strategies in female social insects, whose social life reshapes common trade-offs, such as the one between fecundity and longevity. Interspecific life history variation is associated with colony size, mediated by changes in division of labour and extrinsic mortality. In addition to the ratio of juvenile to adult mortality, social factors such as queen number influence life history trajectories. We discuss two hypotheses explaining why queen fecundity and lifespan is higher in single-queen societies and sugg…
Fitness costs of worker specialization for ant societies
2016
Division of labour is of fundamental importance for the success of societies, yet little is known about how individual specialization affects the fitness of the group as a whole. While specialized workers may be more efficient in the tasks they perform than generalists, they may also lack the flexibility to respond to rapid shifts in task needs. Such rigidity could impose fitness costs when societies face dynamic and unpredictable events, such as an attack by socially parasitic slavemakers. Here, we experimentally assess the colony-level fitness consequences of behavioural specialization in Temnothorax longispinosus ants that are attacked by the slavemaker ant T. americanus . We manipulate…
Gene expression is more strongly associated with behavioural specialization than with age or fertility in ant workers.
2018
The ecological success of social insects is based on division of labour, not only between queens and workers, but also among workers. Whether a worker tends the brood or forages is influenced by age, fertility and nutritional status, with brood carers being younger, more fecund and more corpulent. Here, we experimentally disentangle behavioural specialization from age and fertility in Temnothorax longispinosus ant workers and analyse how these parameters are linked to whole-body gene expression. A total of 3,644 genes were associated with behavioural specialization which is ten times more than associated with age and 50 times more than associated with fertility. Brood carers were characteri…
Changing of the guard: mixed specialization and flexibility in nest defense (Tetragonisca angustula)
2019
Abstract Task allocation is a central challenge of collective behavior in a variety of group-living species, and this is particularly the case for the allocation of social insect workers for group defense. In social insects, both benefits and considerable costs are associated with the production of specialized soldiers. We asked whether colonies mitigate costs of production of specialized soldiers by simultaneously employing behavioral flexibility in nonspecialist workers that can augment defense capabilities at short time scales. We studied colonies of the stingless bee Tetragonisca angustula, a species that has 2 discrete nest-guarding tasks typically performed by majors: hovering guardin…
Time course analysis of the brain transcriptome during transitions between brood care and reproduction in the clonal raider ant
2017
AbstractDivision of labor between reproductive queens and non-reproductive workers that perform brood care is the hallmark of insect societies. However, the molecular basis of this fundamental dichotomy remains poorly understood, in part because the caste of an individual cannot typically be experimentally manipulated at the adult stage. Here we take advantage of the unique biology of the clonal raider ant,Ooceraea biroi, where reproduction and brood care behavior can be experimentally manipulated in adults. To study the molecular regulation of reproduction and brood care, we induced transitions between both states, and monitored brain gene expression at multiple time points. We found that …
Vitellogenin-like A–associated shifts in social cue responsiveness regulate behavioral task specialization in an ant
2018
Division of labor and task specialization explain the success of human and insect societies. Social insect colonies are characterized by division of labor, with workers specializing in brood care early and foraging later in life. Theory posits that this task switching requires shifts in responsiveness to task-related cues, yet experimental evidence is weak. Here, we show that a Vitellogenin (Vg) ortholog identified in an RNAseq study on the ant T. longispinosus is involved in this process: using phylogenetic analyses of Vg and Vg-like genes, we firstly show that this candidate gene does not cluster with the intensively studied honey bee Vg but falls into a separate Vg-like A cluster. Second…
Heritability of Lifetime Income
2013
Using 15 years of data on Finnish twins, we find that 24% (54%) of the variance of women’s (men’s) lifetime income is due to genetic factors and that the contribution of the shared environment is negligible. We link these figures to policy by showing that controlling for education reduces the variance share of genetics by 5-8 percentage points; by demonstrating that income uncertainty has a genetic component half the size of its variance share in lifetime income; and by exploring how the genetic heritability of lifetime income is related to the macroeconomic environment, as measured by GDP growth and the Gini-coefficient of income inequality.
Las "cárceles del capital humano": trabajo y vidas precarias en la juventud universitaria
2017
En los últimos treinta años se ha transitado desde una concepción del capital humano como una macromagnitud económica a una idea de capital humano corporeizada en el individuo. Hemos asistido a una progresiva infiltración de dicha ideología del capital humano también en la vida de la juventud precaria. Nos centramos aquí en los jóvenes universitarios, para quienes el capital humano, ya de forma hegemónica, dirige y marca sus recorridos laborales y vitales. El análisis de los discursos de estos jóvenes nos permitirá explorar desde la imposición de la lógica de la movilidad laboral, a la sujeción a las formas de "emprendedor de sí mismo" y a la normalización, como parte del proceso de incorpo…
Housekeepers and the Siren Call of Hotel Chains
2009
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