Life-history variation in the short-lived herb Rorippa palustris: The role of carbon storage

Abstract In recent years, two approaches have emerged for the analysis of character evolution: the largely statistical “convergence” approach and the mainly cladistic “homology” approach. I discuss the strengths and weaknesses of these approaches as they apply to phylogenetic analyses of life-history variation in birds. Using examples from analyses of character variation in swallows, I suggest that the phylogenetic approach yields distinctive insights into the selective role of the environment and other characters of the organism on the evolution of life-history traits. This view thus has the potential of bringing together micro- and macro-evolutionary views of life-history evolution.

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Starvation reveals the cause of infection-induced castration and gigantism

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2014.1087 ◽

2014 ◽

Vol 281 (1792) ◽

pp. 20141087 ◽

Cited By ~ 19

Author(s):

Clayton E. Cressler ◽

William A. Nelson ◽

Troy Day ◽

Edward McCauley

Keyword(s):

Life History ◽

Energy Budget ◽

Life History Variation ◽

Starvation Stress ◽

Parasite Fitness ◽

Pasteuria Ramosa ◽

Investment In Reproduction ◽

Growth Energy ◽

Host Parasite

Parasites often induce life-history changes in their hosts. In many cases, these infection-induced life-history changes are driven by changes in the pattern of energy allocation and utilization within the host. Because these processes will affect both host and parasite fitness, it can be challenging to determine who benefits from them. Determining the causes and consequences of infection-induced life-history changes requires the ability to experimentally manipulate life history and a framework for connecting life history to host and parasite fitness. Here, we combine a novel starvation manipulation with energy budget models to provide new insights into castration and gigantism in the Daphnia magna – Pasteuria ramosa host–parasite system. Our results show that starvation primarily affects investment in reproduction, and increasing starvation stress reduces gigantism and parasite fitness without affecting castration. These results are consistent with an energetic structure where the parasite uses growth energy as a resource. This finding gives us new understanding of the role of castration and gigantism in this system, and how life-history variation will affect infection outcome and epidemiological dynamics. The approach of combining targeted life-history manipulations with energy budget models can be adapted to understand life-history changes in other disease systems.

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Supplemental Material for The Effect of Early Childhood Intervention on Risk-Taking, Mental Health, and Cognitive Ability: The Mediating Role of Life History Strategy

Evolutionary Behavioral Sciences ◽

10.1037/ebs0000248.supp ◽

2020 ◽

Keyword(s):

Mental Health ◽

Early Childhood ◽

Life History ◽

Cognitive Ability ◽

Risk Taking ◽

Life History Strategy ◽

Early Childhood Intervention ◽

Mediating Role ◽

Childhood Intervention

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Searching for ‘success’: generation, gender and onward migration in the Iranian diaspora

MIGRATION LETTERS ◽

10.33182/ml.v14i1.319 ◽

2017 ◽

Vol 14 (1) ◽

pp. 101-112 ◽

Cited By ~ 1

Author(s):

Melissa Kelly

Keyword(s):

Life History ◽

Young Age ◽

Onward Migration ◽

Social Fields ◽

Transnational Social Fields ◽

High Level ◽

Iranian Diaspora

This article uses the concepts of ‘transnational social fields’ and ‘habitus’ to explore the multifaceted role families play in shaping the aspirations of onward migrating youth. The article draws on biographical life history interviews conducted with the children of Iranian migrants who were raised in Sweden but moved to London, UK as adults. The findings of the study suggest that from a young age, all the participants were pressured by their parents to perform well academically, and to achieve high level careers. These goals were easier to achieve in London than in Sweden for several reasons. Interestingly, however, participants’ understandings of what constituted success and their motivations for onward migration were nuanced and varied considerably by gender. The study contributes to an understanding of the role of multi-sited transnational social fields in shaping the aspirations of migrant youths, as well as the strategies taken up by these migrants to achieve their goals.

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

Gender Questions ◽

10.25159/2412-8457/3660 ◽

2018 ◽

Vol 5 (1) ◽

Cited By ~ 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.

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