scholarly journals Toward a metabolic theory of life history

2019 ◽  
Vol 116 (52) ◽  
pp. 26653-26661 ◽  
Author(s):  
Joseph Robert Burger ◽  
Chen Hou ◽  
James H. Brown

The life histories of animals reflect the allocation of metabolic energy to traits that determine fitness and the pace of living. Here, we extend metabolic theories to address how demography and mass–energy balance constrain allocation of biomass to survival, growth, and reproduction over a life cycle of one generation. We first present data for diverse kinds of animals showing empirical patterns of variation in life-history traits. These patterns are predicted by theory that highlights the effects of 2 fundamental biophysical constraints: demography on number and mortality of offspring; and mass–energy balance on allocation of energy to growth and reproduction. These constraints impose 2 fundamental trade-offs on allocation of assimilated biomass energy to production: between number and size of offspring, and between parental investment and offspring growth. Evolution has generated enormous diversity of body sizes, morphologies, physiologies, ecologies, and life histories across the millions of animal, plant, and microbe species, yet simple rules specified by general equations highlight the underlying unity of life.

2019 ◽  
Author(s):  
Joseph Robert Burger ◽  
Chen Hou ◽  
James H. Brown

SignificanceData and theory reveal how organisms allocate metabolic energy to components of the life history that determine fitness. In each generation animals take up biomass energy from the environment and expended it on survival, growth, and reproduction. Life histories of animals exhibit enormous diversity – from large fish and invertebrates that produce literally millions of tiny eggs and suffer enormous mortality, to mammals and birds that produce a few large offspring with much lower mortality. Yet, underlying this enormous diversity, are general life history rules and tradeoffs due to universal biophysical constraints on the channels of selection. These rules are characterized by general equations that underscore the unity of life.Abstract The life histories of animals reflect the allocation of metabolic energy to traits that determine fitness and the pace of living. Here we extend metabolic theories to address how demography and mass-energy balance constrain allocation of biomass to survival, growth, and reproduction over a life cycle of one generation. We first present data for diverse kinds of animals showing empirical patterns of variation in life history traits. These patterns are predicted by new theory that highlights the effects of two fundamental biophysical constraints: demography on number and mortality of offspring; and mass-energy balance on allocation of energy to growth and reproduction. These constraints impose two fundamental tradeoffs on allocation of assimilated biomass energy to production: between number and size of offspring, and between parental investment and offspring growth. Evolution has generated enormous diversity of body sizes, morphologies, physiologies, ecologies, and life histories across the millions of animal, plant and microbe species, yet simple rules specified by general equations highlight the underlying unity of life.


2011 ◽  
Vol 89 (8) ◽  
pp. 692-704 ◽  
Author(s):  
Evi Paemelaere ◽  
F. Stephen Dobson

The fast–slow continuum hypothesis explains life-history traits as reflecting the causal influence of mortality patterns in interaction with trade-offs among traits, particularly more reproductive effort at a cost of shorter lives. Variation among species of different body sizes produce more or less rapid life cycles (respectively, from small to large species), but the fast–slow continuum remains for birds and mammals when body-size effects are statistically removed. We tested for a fast–slow continuum in mammalian carnivores. We found the above trade-offs initially supported in a sample of 85 species. Body size, however, was strongly associated with phylogeny (ρ = 0.79), and thus we used regression techniques and independent contrasts to make statistical adjustments for both. After adjustments, the life-history trade-offs were not apparent, and few associations of life-history traits were significant. Litter size was negatively associated with age at maturity, but slightly positively associated with offspring mass. Litter size and mass were negatively associated with the length of the developmental period. Gestation length showed weak but significant negative associations with age at maturity and longevity. We conclude that carnivores, despite their wide range of body sizes and variable life histories, at best poorly exhibited a fast–slow continuum.


Author(s):  
Maren N. Vitousek ◽  
Laura A. Schoenle

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.


Author(s):  
Ken H. Andersen

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.


2012 ◽  
Vol 8 (6) ◽  
pp. 1059-1062 ◽  
Author(s):  
Jonathan Z. Shik ◽  
Chen Hou ◽  
Adam Kay ◽  
Michael Kaspari ◽  
James F. Gillooly

Social insect societies dominate many terrestrial ecosystems across the planet. Colony members cooperate to capture and use resources to maximize survival and reproduction. Yet, when compared with solitary organisms, we understand relatively little about the factors responsible for differences in the rates of survival, growth and reproduction among colonies. To explain these differences, we present a mathematical model that predicts these three rates for ant colonies based on the body sizes and metabolic rates of colony members. Specifically, the model predicts that smaller colonies tend to use more energy per gram of biomass, live faster and die younger. Model predictions are supported with data from whole colonies for a diversity of species, with much of the variation in colony-level life history explained based on physiological traits of individual ants. The theory and data presented here provide a first step towards a more general theory of colony life history that applies across species and environments.


1988 ◽  
Vol 66 (8) ◽  
pp. 1906-1912 ◽  
Author(s):  
Todd W. Arnold

Recently, Zammuto (R. M. Zammuto. 1986. Can. J. Zool. 64: 2739–2749) suggested that North American game birds exhibited survival–fecundity trade-offs consistent with the "cost of reproduction" hypothesis. However, there were four serious problems with the data and the analyses that Zammuto used: (i) the species chosen for analysis ("game birds") showed little taxonomic or ecological uniformity, (ii) the measures of future reproductive value (maximum longevity) were severely biased by unequal sample sizes of band recoveries, (iii) the measures of current reproductive effort (clutch sizes) were inappropriate given that most of the birds analyzed produce self-feeding precocial offspring, and (iv) the statistical units used in the majority of analyses (species) were not statistically independent with respect to higher level taxonomy. After correcting these problems, I found little evidence of survival–fecundity trade-offs among precocial game birds, and I attribute most of the explainable variation in life-history traits of these birds to allometry, phylogeny, and geography.


1992 ◽  
Vol 49 (10) ◽  
pp. 2196-2218 ◽  
Author(s):  
Kirk O. Winemiller ◽  
Kenneth A. Rose

Interspecific patterns of fish life histories were evaluated in relation to several theoretical models of life-history evolution. Data were gathered for 216 North American fish species (57 families) to explore relationships among variables and to ordinate species. Multivariate tests, performed on freshwater, marine, and combined data matrices, repeatedly identified a gradient associating later-maturing fishes with higher fecundity, small eggs, and few bouts of reproduction during a short spawning season and the opposite suite of traits with small fishes. A second strong gradient indicated positive associations between parental care, egg size, and extended breeding seasons. Phylogeny affected each variable, and some higher taxonomic groupings were associated with particular life-history strategies. High-fecundity characteristics tended to be associated with large species ranges in the marine environment. Age at maturation, adult growth rate, life span, and egg size positively correlated with anadromy. Parental care was inversely correlated with median latitude. A trilateral continuum based on essential trade-offs among three demographic variables predicts many of the correlations among life-history traits. This framework has implications for predicting population responses to diverse natural and anthropogenic disturbances and provides a basis for comparing responses of different species to the same disturbance.


2005 ◽  
Vol 273 (1587) ◽  
pp. 741-750 ◽  
Author(s):  
Barbara Taborsky

There is increasing evidence that the environment experienced early in life can strongly influence adult life histories. It is largely unknown, however, how past and present conditions influence suites of life-history traits regarding major life-history trade-offs. Especially in animals with indeterminate growth, we may expect that environmental conditions of juveniles and adults independently or interactively influence the life-history trade-off between growth and reproduction after maturation. Juvenile growth conditions may initiate a feedback loop determining adult allocation patterns, triggered by size-dependent mortality risk. I tested this possibility in a long-term growth experiment with mouthbrooding cichlids. Females were raised either on a high-food or low-food diet. After maturation half of them were switched to the opposite treatment, while the other half remained unchanged. Adult growth was determined by current resource availability, but key reproductive traits like reproductive rate and offspring size were only influenced by juvenile growth conditions, irrespective of the ration received as adults. Moreover, the allocation of resources to growth versus reproduction and to offspring number versus size were shaped by juvenile rather than adult ecology. These results indicate that early individual history must be considered when analysing causes of life-history variation in natural populations.


2019 ◽  
Author(s):  
Colin M. Wright ◽  
David N. Fisher ◽  
Wayne V. Nerone ◽  
James L.L. Lichtenstein ◽  
Elizabeth A. Tibbetts ◽  
...  

AbstractColonies of social insects exhibit a spectacular variety of life histories. Here we documented the degree of variation in colony life-history traits, mostly related to productivity, in two species of wild paper wasps. We then tested for associations between colony life-history traits to look for trade-offs or positively associated syndromes, and examined whether individual differences in the behavioral tendencies of foundresses (Polistes metricus) or the number of cofoundresses (P. fuscatus) influenced colony life-history. The majority of our measures of colony life-history were positively related, indicating no obvious resource allocation trade-offs. Instead, the positive association of traits into a productivity syndrome appears to be driven by differences in queen or microhabitat quality. Syndrome structure differed only marginally between species. Queen boldness and body size were not associated with colony life-history inP. metricus. Colonies initiated by multipleP. fuscatusfoundresses were generally more productive, and this advantage was approximately proportional to the number of cofoundresses. These findings demonstrate that colony life-history traits can be associated together much like individual life-history traits, and the associations seen here convey that differences in overall productivity drive between-colony differences in life-history.


2020 ◽  
Author(s):  
Serena Wong ◽  
Jennifer S. Bigman ◽  
Nicholas K. Dulvy

AbstractAll life acquires energy through metabolic processes and that energy is subsequently allocated to life-sustaining functions such as survival, growth, and reproduction. Thus, it has long been assumed that metabolic rate is related to the life history of an organism. Indeed, metabolic rate is commonly believed to set the pace of life by determining where an organism is situated along a fast-slow life history continuum. However, empirical evidence of a relationship between metabolic rate and life histories is lacking, especially for ectothermic organisms. Here, we ask whether three life history traits – maximum body mass, generation length, and growth performance – explain variation in resting metabolic rate (RMR) across fishes. We found that growth performance, which accounts for the trade-off between growth rate and maximum body size, explained variation in RMR, yet maximum body mass and generation length did not. Our results suggest that measures of life history that encompass trade-offs between life history traits, rather than traits in isolation, explain variation in RMR across fishes. Ultimately, understanding the relationship between metabolic rate and life history is crucial to metabolic ecology and has the potential to improve prediction of the ecological risk of data-poor species.


Sign in / Sign up

Export Citation Format

Share Document