Evolutionary Life History Theory Research Articles

Evolutionary life history theory as an organising framework for cohort studies: insights from the Cebu Longitudinal Health and Nutrition Survey

Evolutionary life history theory as an organising framework for cohort studies: insights from the Cebu Longitudinal Health and Nutrition Survey

Are mothers less likely to breastfeed in harsh environments? Physical environmental quality and breastfeeding in the Born in Bradford study.

We use the United Kingdom's Born in Bradford study to investigate whether women in lower quality environments are less likely to breastfeed. We use measures of physical environmental quality (water disinfectant by-products [DBPs], air pollution, passive cigarette smoke, and household condition) alongside socio-economic indicators, to explore in detail how different exposures influence breastfeeding. Drawing on evolutionary life history theory, we predict that lower environmental quality will be associated with lower odds of initiating, and higher hazards of stopping, breastfeeding. As low physical environmental quality may increase the risk of adverse birth outcomes, which may in turn affect breastfeeding chances, we also test for mediation by gestational age, birthweight, head circumference, and abdominal circumference. Our sample is composed of mothers who gave birth at the Bradford Royal Infirmary in West Yorkshire between March 2007 and December 2010 for whom breastfeeding initiation data was available. Analyses were stratified by the two largest ethnic groups: White British (n=3,951) and Pakistani-origin (n=4,411) mothers. After controlling for socio-economic position, Pakistani-origin mothers had lower chances of initiating and higher chances of stopping breastfeeding with increased water DBP exposure (e.g., OR for 0.03-0.61 vs. <0.02μg/day dibromochloromethane exposure 0.70 [0.58-0.83], HR 1.16 [0.99-1.36]), greater air pollution exposure predicted lower chances of initiation for both ethnic groups (e.g., OR for 10μg/m3 increase in nitrogen dioxide 0.81 [0.66-0.99] for White British mothers and 0.79 [0.67-0.94] for Pakistani-origin mothers) but also a reduced hazard of stopping breastfeeding for White British mothers (HR 0.65 [0.52-0.80]), and exposure to household damp/mould predicted higher chances of breastfeeding initiation amongst White British mothers (OR 1.66 [1.11-2.47]). We found no evidence that physical environmental quality effects on breastfeeding were mediated through birth outcomes amongst Pakistani-origin mothers and only weak evidence (p<0.10) amongst White British mothers (exposure to passive cigarette smoke was associated with having lower birthweight infants who were in turn less likely to be breastfed whereas greater air pollution exposure was associated with longer gestations and in turn reduced hazards of stopping breastfeeding). Overall, our findings suggest that there is differential susceptibility to environmental exposures according to ethnicity. Although the water DBP results for Pakistani-origin mothers and air pollution-initiation results for both ethnic groups support our hypothesis that mothers exhibit reduced breastfeeding in poorer quality environments, several physical environmental quality indicators showed null or positive associations with breastfeeding outcomes. We consider physiological explanations for our findings and their implications for life history theory and public health policy.

Low Maternal Capital Predicts Life History Trade-Offs in Daughters: Why Adverse Outcomes Cluster in Individuals.

Background: Some individuals appear prone to multiple adverse outcomes, including poor health, school dropout, risky behavior and early reproduction. This clustering remains poorly understood. Drawing on evolutionary life history theory, we hypothesized that maternal investment in early life would predict the developmental trajectory and adult phenotype of female offspring. Specifically, we predicted that daughters receiving low investment would prioritize the life history functions of “reproduction” and “defense” over “growth” and “maintenance,” increasing the risk of several adverse outcomes.Methods: We investigated 2,091 mother-daughter dyads from a birth cohort in Pelotas, Brazil. We combined data on maternal height, body mass index, income, and education into a composite index of “maternal capital.” Daughter outcomes included reproductive status at 18 years, growth, adult anthropometry, body composition, cardio-metabolic risk, educational attainment, work status, and risky behavior. We tested whether daughters' early reproduction (<18 years) and exposure to low maternal capital were associated with adverse outcomes, and whether this accounted for the clustering of adverse outcomes within individuals.Results: Daughters reproducing early were shorter, more centrally adipose, had less education and demonstrated more risky behavior compared to those not reproducing. Low maternal capital was associated with greater likelihood of the daughter reproducing early, smoking and having committed violent crime. High maternal capital was positively associated with the daughter's birth weight and adult size, and the likelihood of being in school. Associations of maternal capital with cardio-metabolic risk were inconsistent. Daughters reproducing early comprised 14.8% of the population, but accounted for 18% of obesity; 20% of violent crime, low birth weight and short stature; 32% of current smoking; and 52% of school dropout. Exposure to low maternal capital contributed similarly to the clustering of adverse outcomes among daughters. Outcomes were worst among daughters characterized by both low maternal capital and early reproduction.Conclusion: Consistent with life history theory, daughters exposed to low maternal capital demonstrate “future discounting” in behavior and physiology, prioritizing early reproduction over growth, education, and health. Trade-offs associated with low maternal capital and early reproduction contribute to clustering of adverse outcomes. Our approach provides new insight into inter-generational cycles of disadvantage.

Evolutionary Biology: A Basic Science for Medicine

When the Flexner Report was written, evolutionary biology was not yet a well‐developed science and few people were interested in its applications to medicine. As a result, Flexner's recommendations for pre‐medical and medical education did not include evolution. Increasingly, however, physicians and medical scientists are appreciating the clinical relevance of evolutionary biology. The need for antibiotic stewardship to minimize selection for antibiotic resistance and the recognition that cancer is an evolutionary process involving variation and selection among clones of cancer cells have highlighted the urgency of bringing evolutionary principles into medicine. An evolutionary perspective can enhance students' understanding of health and disease in many ways. Evolutionary biology provides an enriched view of variation. Medicine has traditionally considered variations as deviations from a “normal” state. Evolutionary biology recognizes variation, both within populations and between populations, as an important characteristic of biological species. Variation is a prerequisite for selection and, in addition, it provides a defense against the spread of pathogens within populations. This view of variation leads to an understanding of the differences between individual health and population health. The causes of disease in individuals are different from the causes of the incidence of disease in populations. Much of the within‐population variation is genetic while environmental differences are major components of between‐population variation. The focus of medicine on disease in individuals has led to an overemphasis on genetic risk factors and a dependence on pharmacologic therapies. An evolutionary view of population health emphasizes the importance of environmental risk factors or determinants of disease and the possible role of behavioral or cultural interventions in disease prevention. Evolutionary life history theory is an account of the ways in which natural selection has shaped our entire life course. The theory is especially concerned with the acquisition and allocation of metabolic energy and other needed resources. Among other things, we use metabolic energy to build up excess physiological capacities, or reserves, early in development and to prevent or repair the inevitable bodily damage that occurs throughout our lives. Diseases of aging result from unrepaired somatic damage and the depletion of our physiological reserves. This understanding suggests that interventions designed to promote the accumulation of physiological reserves and to slow the accumulation of bodily damage may postpone the onset of diseases of aging. Recognition that signs and symptoms of disease may be adaptations that decrease the fitness loss caused by disease heightens the need for caution in treating the manifestations of disease. These are just a few of the benefits of incorporating evolutionary insights into medicine. Evolutionary biology is a basic science for medicine. Our challenge is to figure out the best ways of integrating evolution into an already overcrowded medical curriculum and of bringing evolution to the attention of busy physicians whose first responsibility is to address the pressing problems of their patients.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Life History Theory and the Industrial Revolution.

The most general theory of life history evolution, that of r versus K selection, implies that innovation in the form of plasticity is more likely to be adaptive under poor rather than good resource conditions, the opposite of how Baumard has it. However, this does focus on benefits rather than costs, and including both allows for greater diversity of outcomes.

Pathogen evolution in finite populations: slow and steady spreads the best.

The theory of life-history evolution provides a powerful framework to understand the evolutionary dynamics of pathogens. It assumes, however, that host populations are large and that one can neglect the effects of demographic stochasticity. Here, we expand the theory to account for the effects of finite population size on the evolution of pathogen virulence. We show that demographic stochasticity introduces additional evolutionary forces that can qualitatively affect the dynamics and the evolutionary outcome. We discuss the importance of the shape of the pathogen fitness landscape on the balance between mutation, selection and genetic drift. This analysis reconciles Adaptive Dynamics with population genetics in finite populations and provides a new theoretical toolbox to study life-history evolution in realistic ecological scenarios.

An evolutionary life history approach to understanding greed

Evolutionary life history theory offers a unifying theoretical framework, emphasizing that human behaviors have been selected because they are adaptive responses to environmental challenges. There is little extant empirical research on the evolutionary origin of greed. The purpose of this study, which was based on the evolutionary life history approach, was to examine the relationships between childhood environmental unpredictability, attachment, and greed. A sample of 364 university students completed measures of greed, attachment, and childhood environment. Structural equation modeling revealed that, as predicted, childhood environmental unpredictability was positively associated with greed. Furthermore, attachment was confirmed as a mediator of the association between childhood environmental unpredictability and greed. These results define the evolutionary origin of greed.

(Re)appreciating the role of life history in eco‐evolutionary dynamics

(Re)appreciating the role of life history in eco‐evolutionary dynamics

Contextual adversity, telomere erosion, pubertal development, and health: Two models of accelerated aging, or one?

Two independent lines of inquiry suggest that growing up under conditions of contextual adversity (e.g., poverty and household chaos) accelerates aging and undermines long-term health. Whereas work addressing the developmental origins of health and disease highlights accelerated-aging effects of contextual adversity on telomere erosion, that informed by an evolutionary analysis of reproductive strategies highlights such effects with regard to pubertal development (in females). That both shorter telomeres early in life and earlier age of menarche are associated with poor health later in life raises the prospect, consistent with evolutionary life-history theory, that these two bodies of theory and research are tapping into the same evolutionary-developmental process whereby longer term health costs are traded off for increased probability of reproducing before dying via a process of accelerated aging. Here we make the case for such a claim, while highlighting biological processes responsible for these effects, as well as unknowns in the epigenetic equation that might instantiate these contextually regulated developmental processes.

Selection on a Subunit of the NURF Chromatin Remodeler Modifies Life History Traits in a Domesticated Strain of Caenorhabditis elegans.

Evolutionary life history theory seeks to explain how reproductive and survival traits are shaped by selection through allocations of an individual’s resources to competing life functions. Although life-history traits evolve rapidly, little is known about the genetic and cellular mechanisms that control and couple these tradeoffs. Here, we find that two laboratory-adapted strains of C. elegans descended from a single common ancestor that lived in the 1950s have differences in a number of life-history traits, including reproductive timing, lifespan, dauer formation, growth rate, and offspring number. We identified a quantitative trait locus (QTL) of large effect that controls 24%–75% of the total trait variance in reproductive timing at various timepoints. Using CRISPR/Cas9-induced genome editing, we show this QTL is due in part to a 60 bp deletion in the 3’ end of the nurf-1 gene, which is orthologous to the human gene encoding the BPTF component of the NURF chromatin remodeling complex. Besides reproduction, nurf-1 also regulates growth rate, lifespan, and dauer formation. The fitness consequences of this deletion are environment specific—it increases fitness in the growth conditions where it was fixed but decreases fitness in alternative laboratory growth conditions. We propose that chromatin remodeling, acting through nurf-1, is a pleiotropic regulator of life history trade-offs underlying the evolution of multiple traits across different species.

Agent-based modelling, molluscan population dynamics, and archaeomalacology

Abstract Agent-based modelling (ABM) is an emerging archaeological tool that offers insights into processes which are archaeologically invisible or difficult to detect. Here we illustrate the potential of ABM for archaeomalacology, posing two research questions and comparing ABM results with Pacific archaeological sequences. The first analysis considers how molluscan energetic return rates (ERR) and age of reproductive maturity (ARM), singularly or in combination, influence prey population resilience. The second analysis assesses how prey spatial structure affects foraging efficiency and prey susceptibility to resource depression. Consistent with expectations from evolutionary ecology and life history theory, the ABM results demonstrate that both ERR and ARM influence prey population resilience (or vulnerability). However, the analysis also demonstrates that ARM is the more important variable and taxa with high ERR (i.e., large-bodied) are disproportionately affected by human harvesting. Not only are efficient foragers more likely to target high ERR taxa, but these prey often have delayed ARM and un-foraged individuals are more likely to be smaller and immature, with disadvantages for population stability and recovery. In short, early-maturing taxa are highly resilient, while late-maturing organisms are more vulnerable; these outcomes also are observed archaeologically. The ABM analyses also demonstrate the effects of prey spatial structure on molluscan susceptibility to resource depression. High prey aggregation initially allows for high foraging efficiency, but prey abundance and encounter rates often rapidly decline. In contrast, when prey are dispersed, search time is greater, leading to lower encounter rates and reduced foraging efficiency, but greater prey population stability. Our ABM and archaeological examples further illustrate that while general principles can be derived, the resilience and spatial structure of specific prey populations, as well as foraging outcomes, are context dependent and continuously evolving. Finally, we note that model departures from theoretical expectations serve to stimulate further research, including use of additional parameters, consideration of novel contextual evidence, and/or investigation of social, technological or environmental hypotheses.

Resource Transfers and Human Life-History Evolution

Formal models of life-history evolution have been used to illuminate both the peculiarities of the human life cycle and its commonalities with those of other taxa. Understanding reproductive decisions in both the contemporary market-based economies of wealthy nation-states and rapidly changing populations largely of the Global South presents particular challenges to evolutionary life-history theory for several reasons. These include (a) the rapidity with which reproductive patterns change, (b) the magnitude of fertility reduction from previous equilibria, and (c) the frequent absence or even reversal of expected wealth-fertility gradients. These empirical challenges have been met to an increasing extent by specifically incorporating durable wealth and resource transfers into more traditional life-history models. Such relatively new models build on classical life-history theory to generate novel predictions. Among these are quite robust predictions that the existence of heritable wealth will decrease optimal fertility and that, once the system of resource transfers is established, fertility and resource transfers will coevolve.

Predicting how many animals will be where: How to build, calibrate and evaluate individual-based models

Individual-based models (IBMs) can simulate the actions of individual animals as they interact with one another and the landscape in which they live. When used in spatially-explicit landscapes IBMs can show how populations change over time in response to management actions. For instance, IBMs are being used to design strategies of conservation and of the exploitation of fisheries, and for assessing the effects on populations of major construction projects and of novel agricultural chemicals. In such real world contexts, it becomes especially important to build IBMs in a principled fashion, and to approach calibration and evaluation systematically. We argue that insights from physiological and behavioural ecology offer a recipe for building realistic models, and that Approximate Bayesian Computation (ABC) is a promising technique for the calibration and evaluation of IBMs.IBMs are constructed primarily from knowledge about individuals. In ecological applications the relevant knowledge is found in physiological and behavioural ecology, and we approach these from an evolutionary perspective by taking into account how physiological and behavioural processes contribute to life histories, and how those life histories evolve. Evolutionary life history theory shows that, other things being equal, organisms should grow to sexual maturity as fast as possible, and then reproduce as fast as possible, while minimising per capita death rate. Physiological and behavioural ecology are largely built on these principles together with the laws of conservation of matter and energy. To complete construction of an IBM information is also needed on the effects of competitors, conspecifics and food scarcity; the maximum rates of ingestion, growth and reproduction, and life-history parameters.Using this knowledge about physiological and behavioural processes provides a principled way to build IBMs, but model parameters vary between species and are often difficult to measure. A common solution is to manually compare model outputs with observations from real landscapes and so to obtain parameters which produce acceptable fits of model to data. However, this procedure can be convoluted and lead to over-calibrated and thus inflexible models. Many formal statistical techniques are unsuitable for use with IBMs, but we argue that ABC offers a potential way forward. It can be used to calibrate and compare complex stochastic models and to assess the uncertainty in their predictions. We describe methods used to implement ABC in an accessible way and illustrate them with examples and discussion of recent studies. Although much progress has been made, theoretical issues remain, and some of these are outlined and discussed.

Life History Predicts Perceptions of Procedural Justice and Crime Reporting Intentions

Evolutionary life history theory (LHT) is a powerful organizing framework central to the life sciences. Interest in biosocial criminology is growing, and adoption of LHT may accelerate progress toward an integrative evolutionarily informed human science. We examined the relationship of life history to attitudes toward the police using data from a demographically representative community-wide survey in a Midwestern county with an urban center exhibiting high rates of violent crimes. As expected, life history was associated with demographic characteristics. Controlling for demographics, slower life history was associated with greater perceptions of procedural justice and police legitimacy, i.e., intentions to contact the police. LHT may promote an integrative human science and a deep theoretical framework for understanding modern social patterns.

Evo-devo of Child Growth: The Role of Weaning in the Transition from Infancy to Childhood

Homo sapiens are unique in having a life history phase of childhood, which follows infancy, as defined by breastfeeding. This review uses evolutionary life history theory in understanding child growth in a broad evolutionary perspective, using the data and theory of evolutionary predictive adaptive growth-related strategies for transition from infancy to childhood. We have previously shown that a delayed infancy–childhood transition has a lifelong impact on stature. Feeding practices during infancy are fundamental elements of nutrition as they program for future growth and body composition. A relationship between the duration of breastfeeding and the nature of weaning has been suggested as a possible cause for later obesity and growth patterns. This review highlights the role that breast milk feeding and variations in the weaning age have on transition to childhood, growth, and body composition.

Too materialistic to get married and have children?

We developed new materials to induce a luxury mindset and activate materialistic values, and examined materialism’s relationship to attitudes toward marriage and having children in Singapore. Path analyses indicated that materialistic values led to more negative attitudes toward marriage, which led to more negative attitudes toward children, which in turn led to a decreased number of children desired. Results across two studies highlight, at the individual level, the tradeoff between materialistic values and attitudes toward marriage and procreation and suggest that a consideration of psychological variables such as materialistic values may allow for a better understanding of larger-scale socioeconomic issues including low fertility rates among developed countries. We discuss implications and describe how psychological factors relating to low fertility fit within evolutionary mismatch and life history theory frameworks.

Selfish goals serve more fundamental social and biological goals.

Proximate selfish goals reflect the machinations of more fundamental goals such as self-protection and reproduction. Evolutionary life history theory allows us to make predictions about which goals are prioritized over others, which stimuli release which goals, and how the stages of cognitive processing are selectively influenced to better achieve the aims of those goals.

A Life History Theory of Father Absence and Menarche: A Meta-Analysis

Is the absence of biological fathers related to their daughters' earlier age at menarche? Drawing on evolutionary psychology and life history theory, prior research has suggested such a relationship (Belsky, Steinberg, and Draper, 1991; Draper and Harpending, 1982; Ellis, 2004). Although qualitative reviews have shown narrative support for this relationship (Allison and Hyde, 2013; Ellis, 2004; Kim, Smith, and Palermiti, 1997; Susman and Dorn, 2009), no quantitative review exists to provide empirical support for this relationship or to explain mixed results. Thus, we conducted a random-effects meta-analysis of correlations (Card, 2012) on father absence and daughter menarcheal age (k=33; N=70,403). The weighted mean correlation was .14, 95% CI [.09, .19], suggesting that father absence was significantly related to earlier menarche; effect sizes were heterogeneous. Egger's regression (Egger, Smith, Schneider, and Minder, 1997) showed no evidence of publication bias (file-drawer effect; r=.34, p=.052). Outcome measure differences (menarcheal age vs. menarcheal age embedded in a multi-item pubertal timing scale) did not moderate effect sizes. Study year effects (Schooler, 2011) were also non-significant. Our findings support one aspect of the life history model and provide groundwork for subsequent examination of other pathways in the model.

Utilizing Evolutionary Life History Theories in Family Studies

To provide a more holistic view of the family, scholars seek theoretical principles that can bridge and enhance existing paradigms. In this article, we introduce evolutionary life history theory and describe 4 midlevel life history theories (psychosocial acceleration, paternal investment, differential susceptibility, and parent‐offspring conflict). These theories will enable family scholars to expand their understanding of contemporary human families from an evolutionary perspective by creating novel research questions that will lead to innovative, interdisciplinary research.

Post-reproductive life span and demographic stability

Recent field studies suggest that it is common in nature for animals to outlive their reproductive viability. Post-reproductive life span has been observed in a broad range of vertebrate and invertebrate species. But post-reproductive life span poses a paradox for traditional theories of life history evolution. The commonly cited explanation is the "grandmother hypothesis", which applies only to higher, social mammals. We propose that post-reproductive life span evolves to stabilize predator-prey population dynamics, avoiding local extinctions. In the absence of senescence, juveniles would be the most susceptible age class. If juveniles are the first to disappear when predation pressure is high, this amplifies the population's risk of extinction. A class of older, senescent individuals can help shield the juveniles from predation, stabilizing demographics and avoiding extinction. If, in addition, the life history is arranged so that the older individuals are no longer fertile, the stabilizing effect is further enhanced.