scholarly journals Dispersal, dormancy and life-history tradeoffs at the individual, population and species levels in southern African Asteraceae

2015 ◽  
Vol 210 (1) ◽  
pp. 356-365 ◽  
Author(s):  
Caroli de Waal ◽  
Bruce Anderson ◽  
Allan G. Ellis
Keyword(s):  
Life History ◽  
Life History Tradeoffs ◽  
The Individual

Queering Gender Identity Work: A Life History of a Black Transgender Woman

2018 ◽  
Vol 5 (1) ◽  
Author(s):  
Esethu Monakali
Keyword(s):  
Life History ◽  
Gender Identity ◽  
Public Spaces ◽  
Identity Work ◽  
Social Identities ◽  
Gender And Sexuality ◽  
Ongoing Effort ◽  
History Of ◽  
The Individual

This article offers an analysis of the identity work of a black transgender woman through life history research. Identity work pertains to the ongoing effort of authoring oneself and positions the individual as the agent; not a passive recipient of identity scripts. The findings draw from three life history interviews. Using thematic analysis, the following themes emerge: institutionalisation of gender norms; gender and sexuality unintelligibility; transitioning and passing; and lastly, gender expression and public spaces. The discussion follows from a poststructuralist conception of identity, which frames identity as fluid and as being continually established. The study contends that identity work is a complex and fragmented process, which is shaped by other social identities. To that end, the study also acknowledges the role of collective agency in shaping gender identity.

scholarly journals Fitness costs of parasites explain multiple life history tradeoffs in a wild mammal

2020 ◽  
Author(s):  
Gregory F Albery ◽  
Alison Morris ◽  
Sean Morris ◽  
Fiona Kenyon ◽  
Daniel H Nussey ◽  
...  
Keyword(s):  
Life History ◽  
Fitness Costs ◽  
Wild Mammal ◽  
Life History Tradeoffs

scholarly journals Phenotypic plasticity of labile traits in the wild

2013 ◽  
Vol 59 (4) ◽  
pp. 485-505 ◽  
Author(s):  
Jon E. Brommer
Keyword(s):  
Life History ◽  
Phenotypic Plasticity ◽  
Statistical Approach ◽  
Scale Up ◽  
Population Level ◽  
Wild Populations ◽  
Quantitative Genetic ◽  
In The Wild ◽  
The Individual ◽  
Quantitative Genetic Parameters

Abstract Individual-based studies allow quantification of phenotypic plasticity in behavioural, life-history and other labile traits. The study of phenotypic plasticity in the wild can shed new light on the ultimate objectives (1) whether plasticity itself can evolve or is constrained by its genetic architecture, and (2) whether plasticity is associated to other traits, including fitness (selection). I describe the main statistical approach for how repeated records of individuals and a description of the environment (E) allow quantification of variation in plasticity across individuals (IxE) and genotypes (GxE) in wild populations. Based on a literature review of life-history and behavioural studies on plasticity in the wild, I discuss the present state of the two objectives listed above. Few studies have quantified GxE of labile traits in wild populations, and it is likely that power to detect statistically significant GxE is lacking. Apart from the issue of whether it is heritable, plasticity tends to correlate with average trait expression (not fully supported by the few genetic estimates available) and may thus be evolutionary constrained in this way. Individual-specific estimates of plasticity tend to be related to other traits of the individual (including fitness), but these analyses may be anti-conservative because they predominantly concern stats-on-stats. Despite the increased interest in plasticity in wild populations, the putative lack of power to detect GxE in such populations hinders achieving general insights. I discuss possible steps to invigorate the field by moving away from simply testing for presence of GxE to analyses that ‘scale up’ to population level processes and by the development of new behavioural theory to identify quantitative genetic parameters which can be estimated.

scholarly journals Dentinal anomalies in teeth of harbour porpoises (Phocoena phocoena) from Scottish waters: are they linked to sexual maturation and environmental events?

2009 ◽  
Vol 89 (5) ◽  
pp. 893-902 ◽  
Author(s):  
P.L. Luque ◽  
G.J. Pierce ◽  
J.A. Learmonth ◽  
M.B. Santos ◽  
E. Ieno ◽  
...  
Keyword(s):  
Life History ◽  
Sexual Maturation ◽  
Time Course ◽  
Physiological Stress ◽  
Organic Pollutant ◽  
Additive Models ◽  
Phocoena Phocoena ◽  
Major Life ◽  
The Individual ◽  
Pulp Stones

We examined the tooth ultra-structure of harbour porpoises (Phocoena phocoena) from Scottish waters to determine whether the incidence of mineralization anomalies could be related to certain life history events (e.g. the achievement of sexual maturation) as well as other factors that affect the general health of the individual (e.g. persistent organic pollutant (POP) concentrations in blubber). Five distinct types of mineralization anomalies were recorded: accessory lines, marker lines, dentinal resorption, cemental disturbance and pulp stones and the occurrence of these anomalies was scored by sex, age and maturity state. Overall, the incidence of mineralization anomalies was high and tended to increase with age. Marker lines and accessory lines were the most commonly recorded anomalies while pulp stones were least frequent. Duplicate teeth (i.e. from the same individual) always showed the same pattern of anomaly occurrence.Fitted binary generalized linear and additive models indicated that the presence of dentinal resorption, cemental disturbance and marker lines in harbour porpoise teeth increased with age, body length and maturity. Males displayed marker lines more frequently than females. Age was the best predictor of the incidence of dentinal resorption and cemental disturbance while age and sex were the best predictors of the incidence of marker lines. The time course of appearance of dentinal resorption and cemental disturbance suggests that their occurrence could be related to physiological stress linked to sexual maturation. Marker lines were found within growth layer groups which coincided with the beginning of weaning and sexual maturation, suggesting an association with these two major life history events. Accessory lines were found in most teeth and may be a normal characteristic of porpoise teeth or reflect regular events. Pulp stones appeared only in mature animals. We found no evidence that the presence of anomalies in teeth was significantly related to POP concentrations in the blubber.

Life-history tradeoffs revealed by seasonal declines in reproductive traits of Arctic-breeding shorebirds

2018 ◽  
Vol 49 (2) ◽  
pp. jav-01531 ◽  
Author(s):  
Emily L. Weiser ◽  
Stephen C. Brown ◽  
Richard B. Lanctot ◽  
H. River Gates ◽  
Kenneth F. Abraham ◽  
...  
Keyword(s):  
Life History ◽  
Reproductive Traits ◽  
Life History Tradeoffs

scholarly journals Major Evolutionary Transitions in Social Insects, the Importance of Worker Sterility and Life History Trade-Offs

2021 ◽  
Vol 9 ◽  
Author(s):  
Abel Bernadou ◽  
Boris H. Kramer ◽  
Judith Korb
Keyword(s):  
Life History ◽  
Social Insects ◽  
Division Of Labour ◽  
Evolutionary Transitions ◽  
Individual Level ◽  
Individual Fitness ◽  
Trade Offs ◽  
Group Members ◽  
The Individual ◽  
Worker Sterility

The evolution of eusociality in social insects, such as termites, ants, and some bees and wasps, has been regarded as a major evolutionary transition (MET). Yet, there is some debate whether all species qualify. Here, we argue that worker sterility is a decisive criterion to determine whether species have passed a MET (= superorganisms), or not. When workers are sterile, reproductive interests align among group members as individual fitness is transferred to the colony level. Division of labour among cooperating units is a major driver that favours the evolution of METs across all biological scales. Many METs are characterised by a differentiation into reproductive versus maintenance functions. In social insects, the queen specialises on reproduction while workers take over maintenance functions such as food provisioning. Such division of labour allows specialisation and it reshapes life history trade-offs among cooperating units. For instance, individuals within colonies of social insects can overcome the omnipresent fecundity/longevity trade-off, which limits reproductive success in organisms, when increased fecundity shortens lifespan. Social insect queens (particularly in superorganismal species) can reach adult lifespans of several decades and are among the most fecund terrestrial animals. The resulting enormous reproductive output may contribute to explain why some genera of social insects became so successful. Indeed, superorganismal ant lineages have more species than those that have not passed a MET. We conclude that the release from life history constraints at the individual level is a important, yet understudied, factor across METs to explain their evolutionary success.

Whether Mahatma Gandhi Was Misinterpreted Through the Dilemma of Irrelevant and Relevant Philosophies?

2021 ◽  
pp. 0972558X2110571
Author(s):  
Mithun Sikdar
Keyword(s):  
Life History ◽  
Life Experiences ◽  
Sexual Life ◽  
Health Food ◽  
Social Scientists ◽  
Mahatma Gandhi ◽  
Current Anthropology ◽  
The Individual ◽  
Life History Study

In one of the articles published in Current Anthropology way back in 1973, David G. Mandelbaum talked about two approaches to understand the life of an individual. For him, to observe the lifestyle of a person or gain the knowledge about a lifestyle of a person, social scientists always succumb to two main approaches: life passage studies and life history studies. Life passage studies understand the contribution of society about the socialization and enculturation of their young ones, whereas life history studies emphasize the personified experiences and requirements of the individuals and how the individual copes up with the society. Here I have adopted the means of life history study to see some of the facets of Gandhiji’s life and its influence in the society. I shall do it by looking at some of his philosophies on health, food, sexual life, rather than going into the details of his whole life history. I shall do it without perplexing my own way of understanding “Mahatma” and linking sometimes my own life experiences that had been influenced by the philosophies of Gandhiji. I shall be carrying out an autoethnography by perceiving the virtues of Gandhiji in my own life. Nevertheless, it will rather be a futile exercise to describe his philosophies in a single paper and that too with a minimum experience on his whole life.

Individual Growth and Reproduction

2019 ◽  
pp. 38-56
Author(s):  
Ken H. Andersen
Keyword(s):  
Life History ◽  
Growth Model ◽  
Life Histories ◽  
Maximum Size ◽  
Individual Growth ◽  
Energy Budgets ◽  
Asymptotic Size ◽  
The Individual ◽  
Growth And Reproduction

This chapter develops descriptions of how individuals grow and reproduce. More specifically, the chapter seeks to determine the growth and reproduction rates from the consumption rate, by developing an energy budget of the individual as a function of size. To that end, the chapter addresses the question of how an individual makes use of the energy acquired from consumption. It sets up the energy budgets of individuals by formulating the growth model using so-called life-history invariants, which are parameters that do not vary systematically between species. While the formulation of the growth model in terms of life-history invariants is largely successful, there is in particular one parameter that is not invariant between life histories: the asymptotic size (maximum size) of individuals in the population. This parameter plays the role of a master trait that characterizes most of the variation between life histories.

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