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.

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.

Hormones and Behavior

2019 ◽  
pp. 11-26
Author(s):  
Maren N. Vitousek ◽  
Laura A. Schoenle
Keyword(s):  
Life History ◽  
Life Histories ◽  
Life History Traits ◽  
Developmental Plasticity ◽  
Endocrine System ◽  
Phenotypic Traits ◽  
Social Environments ◽  
Trade Offs ◽  
And Behavior

Hormones mediate the expression of life history traits—phenotypic traits that contribute to lifetime fitness (i.e., reproductive timing, growth rate, number and size of offspring). The endocrine system shapes phenotype by organizing tissues during developmental periods and by activating changes in behavior, physiology, and morphology in response to varying physical and social environments. Because hormones can simultaneously regulate many traits (hormonal pleiotropy), they are important mediators of life history trade-offs among growth, reproduction, and survival. This chapter reviews the role of hormones in shaping life histories with an emphasis on developmental plasticity and reversible flexibility in endocrine and life history traits. It also discusses the advantages of studying hormone–behavior interactions from an evolutionary perspective. Recent research in evolutionary endocrinology has provided insight into the heritability of endocrine traits, how selection on hormone systems may influence the evolution of life histories, and the role of hormonal pleiotropy in driving or constraining evolution.

scholarly journals Alternative Migratory Strategies Related to Life History Differences in the Walleye (Sander Vitreus)

2021 ◽  
Author(s):  
Graydon McKee ◽  
Rachael Hornsby ◽  
Friedrich Fischer ◽  
Erin S. Dunlop ◽  
Robert Mackereth ◽  
...  
Keyword(s):  
Life History ◽  
Acoustic Telemetry ◽  
Late Summer ◽  
Maximum Size ◽  
Individual Growth ◽  
Sander Vitreus ◽  
Differential Growth ◽  
Individual Behaviour ◽  
Pace Of Life ◽  
Average Maximum

Abstract BackgroundWhile Pace of Life Syndrome predicts behavioural differences between individuals with differential growth and survival, testing these predictions in nature is challenging due to difficulties with measuring individual behaviour in the field. However, recent advances in acoustic telemetry technology have facilitated measurements of individual behaviour at scales not previously possible in aquatic ecosystems. MethodsUsing a Walleye (Sander vitreus) population inhabiting Black Bay, Lake Superior, we examine whether life history characteristics differ between more and less mobile individuals as predicted by Pace of Life Syndrome. We tracked the movement of 192 individuals from 2016-2019 using an acoustic telemetry study, relating patterns in annual migratory behaviour to individual growth, and seasonal changes in optimal thermal-optical habitat. ResultsWe observed two consistent movement patterns in our study population — migratory individuals left Black Bay during late summer to early fall before returning to the bay, whereas residents remained within the bay year-round. The average maximum length of migrant Walleye was 5.5 cm longer than residents, and the sex ratios of Walleye caught during fall surveys was increasingly female-biased towards the mouth of Black Bay, suggesting that a majority of migrants were females. Further, Walleye occupancy outside of Black Bay was positively associated with increasing thermal-optical habitat. ConclusionsWalleye in Black Bay appear to conform to Pace of Life Syndrome, with more exploratory (migrant) individuals gaining increased fitness through increased maximum size, which, given size-dependent fecundity in this species, likely results in greater reproductive success (via greater egg deposition vs. non-migrants). Further, apparent environmental (thermal) controls on migration suggest that migratory Walleye (more so than residents) may be more sensitive to changing environmental conditions (e.g., warming climate) than residents.

Use of Time in the Phenology of Horizontal Species Interactions

2019 ◽  
pp. 107-132
Author(s):  
Eric Post
Keyword(s):  
Life History ◽  
Species Interactions ◽  
Local Community ◽  
Species Assemblage ◽  
Competing Interests ◽  
Use Of Time ◽  
Allocation Of Time ◽  
The Individual ◽  
Competition For Resources

This chapter addresses the role of time in horizontal species interactions. Horizontal, or lateral, species interactions are those involving individuals within a single trophic level in the same local community or species assemblage. These involve primarily interference interactions such as competition for resources required by more than one member of the local assemblage. The chapter then considers the allocation of time within an individual organism's life history cycle. The use of time by the individual must address potentially strongly competing interests. In a competitive context, while earlier timing of life history events may in and of itself present a competitive advantage among conspecifics, its value as a strategy in interspecific competition relates to its effect on phenological duration. This is because duration determines overlap within the phenological community.

Issues Based on Species Life History and Behavior

2021 ◽  
pp. 89-94
Author(s):  
Joseph A. Veech
Keyword(s):  
Life History ◽  
Habitat Use ◽  
Life Histories ◽  
Radio Telemetry ◽  
Spatial Scales ◽  
Habitat Associations ◽  
Habitat Characteristics ◽  
Habitat Analysis ◽  
The Individual ◽  
And Behavior

Species vary tremendously in their life histories and behavior. The particular life history traits and behavior of the focal species must be considered when designing a study to examine habitat associations. For some species, individuals use different areas (of the landscape or territory) for breeding and foraging. As such, the important characteristics for the foraging and breeding habitats may be different. The dramatically different life stages of some organisms (e.g., amphibians and some insects) often correspond to equally dramatic differences in habitat use between juveniles and adults. For some species, habitat use differs among seasons. Species that are highly mobile and have individuals that move around substantially on a daily or weekly basis are particularly challenging for a habitat analysis. For these species, the most efficient and appropriate study design may be one that tracks individuals (through radio-telemetry or GPS) and analyzes the environmental or habitat characteristics at locations where the individual has stopped, rather than trying to survey for the species in pre-established and insufficiently small survey plots. In addition, individual movement and the issues mentioned above may necessitate that environmental variables are measured and analyzed at multiple spatial scales.

The role of dispersal and retention in the early life stages of shrimp in a lowland river

2010 ◽  
Vol 67 (4) ◽  
pp. 720-729 ◽  
Author(s):  
Amina E. Price ◽  
Paul Humphries
Keyword(s):  
Life History ◽  
Life Histories ◽  
Movement Patterns ◽  
Early Ontogeny ◽  
Small Scale ◽  
Lowland River ◽  
Southeastern Australia ◽  
Stage Of Development ◽  
Paratya Australiensis

This study investigated the importance of dispersal and retention processes during early ontogeny for three caridean shrimp species that complete their entire life history in freshwater. Directional traps were used to examine the small-scale movement patterns of shrimp into and out of nursery habitat patches (slackwaters) in a small lowland river in southeastern Australia. Movement patterns provided evidence for two contrasting life history based dispersal and retention strategies. For the two smaller atyid species, Paratya australiensis and Caridina mccullochi , the majority of larvae remained within the slackwater in which they were hatched until the final stage of development, at which point dispersal, either among slackwaters or out of slackwaters to faster-flowing pool and run habitats, occurred. For the larger palaemonid species, Macrobrachium australiense , larvae were hatched into slackwaters and dispersal occurred predominately during the first stage of larval development and then decreased as development progressed. Despite the differences in dispersal strategies among species, movement was mostly associated with a particular larval stage and thus emphasizes the importance of retention during critical developmental periods and of the potential impact that flow alteration could have on these and other species with similar life histories.

Example Four: Facultative Anadromy in Salmonid Fishes

2020 ◽  
pp. 86-92
Keyword(s):  
Life History ◽  
Life Histories ◽  
Population Level ◽  
Dynamic State ◽  
Salmonid Fishes ◽  
Individual Level ◽  
State Variable ◽  
Level Model ◽  
Fitness Benefits ◽  
The Individual

This chapter offers a fourth example model, with the objective of (1) illustrating the application of state- and prediction-based theory (SPT) to a new kind of decision—a life history decision—in a case where dynamic state variable modeling (DSVM) has been applied successfully; and (2) describing the unique ability of models utilizing SPT to address population-level questions of particular interest to conservationists and managers. In this case, SPT produced individual-level decisions similar to those of DSVM, but including them in a population-level model led to quite different conclusions than those implied by the individual-level DSVM analysis. Salmonid fishes exhibit amazing life history diversity. One fundamental distinction among salmonid life histories is whether or not individuals migrate to the ocean. In general, facultative anadromy can be seen as an adaptive behavior that trades off the fitness benefits of going to the ocean versus those of remaining resident. The anadromy versus residency decision is important to fish conservation and resource management.

scholarly journals Life cycle of Scapholeberis armata freyi Dumont & Pensaert, 1983 (Cladocera, Daphnidae)

2012 ◽  
Vol 12 (4) ◽  
pp. 56-60 ◽  
Author(s):  
Maria Carolina de Almeida Castilho ◽  
Célio Wisniewski ◽  
Maria José dos Santos-Wisniewski
Keyword(s):  
Life Cycle ◽  
Secondary Production ◽  
Egg Production ◽  
Maximum Size ◽  
Culture Conditions ◽  
Individual Growth ◽  
Mixed Suspension ◽  
Algal Suspension ◽  
The Mean

Knowledge of the life cycle of zooplankton species can provide information for a better understanding of the role of each species in the community and basic data for secondary production investigations. In this study, some life-cycle traits were measured for Scapholeberis armata freyi Dumont & Pensaert, 1983 (Cladocera, Daphnidae), maintained under controlled conditions in laboratory cultures. Experiments were carried out in incubators at a temperature of 23.0 ºC, photoperiod of 12 hours light/dark, and food supply (algal suspension of the chlorophycean Pseudokirchneriela subcapitata at 10(5) cells.mL-1 and mixed suspension of yeast, and fish ration added per organism, at equal proportions) that were kept constant. Observations were made once or twice a day to record individual growth, age and size of primipara, as well as fecundity and longevity. S. armata freyi achieved a maximum size of 827 µm, while the primiparous instar measured 542 µm on average, at an age of 5.86 days. The mean fecundity was 8 eggs.female-1 and the mean of total number of eggs produced by a female was 47.58. Embryonic development time was 1.9 days and the maximum longevity found was 31 days. In this study, the life cycle parameters of S. armata freyi presented are close to those found in other species of Daphnidae, under the same culture conditions of temperature and photoperiod. However, the longevity was greater than other species that received algae as food only. The quality and quantity of food are factors that control secondary production in aquatic ecosystems and an increase of food availability increases longevity and egg production. Thus the greater longevity and egg production observed for S. armata freyi can influence its secondary production.

Production of Larvae of Phyllobius piri L. (Col. Curculionidae) in an Abandoned Field

1973 ◽  
Vol 4 (1) ◽  
pp. 21-29 ◽  
Author(s):  
S. Larsson ◽  
T. Persson ◽  
U. Lohm ◽  
B. Axelsson
Keyword(s):  
Life History ◽  
Life Table ◽  
Growth Curve ◽  
Individual Growth ◽  
Abandoned Field ◽  
Individual Growth Curve ◽  
History Of ◽  
The Individual

AbstractThe abundance of the larvae of Phyllobius piri L. and P. viridicollis F. (Col. Curculionidae) was investigated in an abandoned field in central Sweden. On the basis of the individual growth curve and the life table of the larvae the production of P. piri was calculated to be 4.6 ± I.9 g dw per m2 or 25 ± II kcal per m2 (mean ± 95 per cent c.i.). The population of the hibernating pupae of P. piri was about 500 per m2 during three successive years. During the same period the abundance of hibernating larvae of P. viridicollis was I00-250 per m2. Notes are given on the life history of the two species. The larvae are described by B. Lekander in an appendix.

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