Life History Strategies

8 Key excerpts on "Life History Strategies"

• 

  eBook - PDF

  Sex Differences

  Developmental and Evolutionary Strategies

  • Linda Mealey(Author)
  • 2000(Publication Date)
  • Academic Press

    (Publisher)

  Thus, the life-history strategies of species that frequently interact coevolve to reach a stable equilibrium. Some tactics and strategies may lead to either a beneficial or a deleterious outcome depending on circumstances. The result is that some traits will not become fixed, but will continue to vary within a species and even within individuals at different times. From this perspective, life history can be viewed as a developmental process as well as an evolutionary process, with strategic choice-points (not necessar- ily implying conscious choice) occuring throughout an individual life span (Domi- ney, 1984). To date, most developmental life-history models address variation in reproduc- tive behavior, such as the timing of sexual maturity, the number of offspring con- ceived or hatched in a single parenting event, and keeping or deserting a mate. Game theory modeling can also be applied to other “strategies” such as habitat selection; immigration and emigration; and, in humans, behaviors such as occupa- tional choice, financial risk taking, and even crime. For all these life decisions (play options) the costs and benefits (payoffs) will depend, in complex relation, on the behaviors of others. Game theory models demonstrate that in many types of “contests,” versatility can be more advantageous than the use of any particular fixed strategy. As Alexan- der (1986) writes, “It would be the worst of all strategies to enter the competition and cooperativeness of social life, in which others are prepared to alter their re- sponses, with only preprogrammed behaviors” (p. 171). Because they show how mixed strategies may be evolutionarily stable in the long term, game theory models can help us to understand the ultimate reasons behind the selection for, and mainte- nance of, genetic diversity and behavioral flexibility. Such “mixed ESSs” can theoretically be maintained in at least five ways (after Buss, 1991; and Mealey, 1995a).

  Sign up to read

  Learn more about book
• 

  eBook - PDF

  Evolutionary Ecology of Plant-Plant Interactions

  An Empirical Modelling Approach

  • Christian Damgaard(Author)
  • 2005(Publication Date)
  • Aarhus University Press

    (Publisher)

  7. Evolution of plant life history Trade-offs and evolutionary stable strategies If relevant genetic variation is available in a plant population, the proc- ess of natural selection will cause evolution (Darwin 1859), i.e., the phys- iology, morphology and life history of the plant population will adapt to the present abiotic and biotic environment. Since evolution depends on the process of natural selection, the type of evolutionary changes are limited by the mechanisms of natural selection and often, but certainly not always (Lewontin 1970), this means that the evolutionary changes should be explained at the level of the fitness of the individual plant. A plant with a given amount of resources at a certain point in time may allocate its resources to different purposes determined by the evolved life history of the plant and impulses from the environment. For example, an annual plant will usually allocate all its resources to re- production at the end of the growing season, whereas a perennial plant only can allocate a fraction of its resources to reproduction (e.g. Harper 1977). Some of the resources of the perennial plant need to be stored to survive during harsh periods, e.g. during a drought or a winter period. The perennial plant is said to make a trade-off between reproduction and survival, and since both features are important for the individual fitness of the plant this trade-off will be under selective pressure. The characteristic life history of a specific plant species will to a large extent often be determined by the way natural selection has shaped the morphological and physiological features underlying the various trade- offs. Other trade-offs that are being selected to increase the fitness of the individual plant at its particular environment include the allocation between male and female sexual structures, and the allocation between structures that will increase growth, e.g. stems and leaves, and a general storage of resources (e.g. Harper 1977).

  Sign up to read

  Learn more about book
• 

  eBook - PDF

  Insect Ecology

  Behavior, Populations and Communities

  • Peter W. Price, Robert F. Denno, Micky D. Eubanks, Deborah L. Finke, Ian Kaplan(Authors)
  • 2011(Publication Date)
  • Cambridge University Press

    (Publisher)

  Rather, the terms are a short hand which covers the more cumbersome, but correct approach, of saying that a particular trait changed passively under the influence of natural selection. Such natural selection may have worked over the long term, gradually resulting in a syndrome of adaptations which meets environmental challenges and promotes population persistence of a species. The full syndrome of adaptations could be seen as the adaptive strategy, or evolutionary strategy, comprising for example, in Prokelisia plant hoppers, wing polymorphism, the response to density, cibarial pump design, and changes in fecundity in response to crowding. These combined tactics encompass the individual adaptations and their physiological mechanisms by which the strategy is achieved. 10.3 Comparative life-history studies Life-history variation and evolutionary conservation can be observed at every level of organization in insects. Related species differ in their evolutionary strategies, while showing some strong effects of phylogenetic constraints. There is 374 Life histories variation in life-history traits among populations of a species over whole landscapes, and within populations lineages may also differ in many life-history characteristics. In the following sections we will consider examples of each level of variation to illustrate the way that life-history studies have been approached by insect ecologists. 10.3.1 Comparisons among species: parasitoids Some features of the parasitoid life cycle have been discussed in previous chapters, so we are familiar with their basic life-history traits. In Chapter 8 ( Figure 8.4 ) convergence in ovariole number per female was illustrated, showing in both ichneumonid wasps and tachinid flies that ovariole number and fecundity declined as species attacked the depleted number of hosts available as the host life cycle progressed from eggs to pupae and adults.

  Sign up to read

  Learn more about book
• 

  eBook - PDF

  Biological Approaches and Evolutionary Trends in Plants

  • Shoichi Kawano(Author)
  • 2012(Publication Date)
  • Academic Press

    (Publisher)

  Ecology 64,16-24. Leon, J.A. (1976). Life histories as adaptive strategies. /. theor. Biol. 60, 301-335. Makela, A. (1985). Differential games in evolutionary theory, height growth strategies of trees. Theor. Pop. Biol. 27, 239-267. Mangel, M. (1985). Decision and control in uncertain resource systems. Academic Press. Mangel, M. and Clark, C.W. (1988). Dynamic modelling of behavior. Princeton Univ. Press, Princeton. Marks, P. (1975). On the relation between extension growth and successional status of deciduous trees of the northeastern United States. Bull. Torrey Bot. Club. 102, 172-177. Maruyama, K. (1978). Shoot elongation characteristics and phenological behavior of forest trees in natural beech forest: ecological studies on natural beech forest (32). Bull. Niigata Univ. Forest. 11, 1-30. (in Japanese with English summary). Mirmirani, M. and Oster, G. (1978). Competition, kin selection, and evolutionary stable strate-gies. Theor. Pop. Biol. 13, 304-339. Penning de Vries, F.W.T., Brunsting, A. and van Laar, H. (1974). Products, requirements and effi-ciency of biosynthesis: a quantitative approach. /. theor. Biol. 45, 339-377. Pianka, E. (1976). Natural selection of optimal reproductive tactics. Am. Zool. 16, 775-784. Pontryagin, L.S., Boltyanskii, V.G., Gamkrelidze, R.V. and Mischenko, E.F. (1962). The math-ematical theory of optimal processes. trans, by K.N. Trirogoff. Interscience Pub., John Wiley 19 Optimal Growth Schedule 349 & Sons, New York. Pugliese, A. (1988). Optimal resource allocation in perennial plants: a continuous-time model. Theor. Pop. Biol. 34, 215-247. Russell, R.S. (1977). Plant root systems: their function and interaction with soil. London: McGraw Hill Schaffer, W.M. (1974). Selection for optimal life histories: the effects of age structure. Ecology 55, 291-303. Schaffer, W.M. (1983). The application of optimal control theory to the general life history prob-lem. Am. Nat. 121, 418-431. Schaffer, W.M. and Schaffer, M.V.

  Sign up to read

  Learn more about book
• 

  eBook - PDF

  The Evolving Female

  A Life History Perspective

  • Mary Ellen Morbeck, Alison Galloway, Adrienne Zihlman, Mary Ellen Morbeck, Alison Galloway, Adrienne Zihlman, Adrienne L. Zihlman, Mary Morbeck, Alison Galloway, Adrienne Zihlman(Authors)
  • 1996(Publication Date)
  • Princeton University Press

    (Publisher)

  Furthermore, in this oretical constraints. reductionist version of life history, the survival Population Biology and Life-History Theory features such as locomotion, feeding, predator avoidance, and social behavior so critical throughout life are assumed or, too often, Most current definitions of life history are never considered. part of the tradition of population-biological One of the central features in conventional life-history theory as part of populational stud- studies. Life-history theory can be seen to fall ies is the concept of “trade-offs” in which the into two different emphases (e.g., Lessells Introduction xvi life-history attributes are balanced against each with a framework for organizing information at other. These trade-offs link traits that constrain the populational level or higher. Since we are ultimately interested in how evolution works, or limit their simultaneous action and evolu- tion. Using this concept, an individual’s cur- we focus on the individual and its links to its rent reproduction is suggested to imperil cur- population. We broaden our interests beyond rent survival and also have an impact on future counting time to document how each individ- ual’s life plays out through the life stages and reproduction. “Because energy used for one its survival and reproductive outcome. Our purpose cannot be used for another purpose, focus on the individual rather than including living organisms face a series of trade-offs through time. The two most fundamental individuals only in central-tendency statistics trade-offs, which are at the center of all life- sets us apart from the more conventional life- history theory, are those between current and history theorists.

  Sign up to read

  Learn more about book
• 

  eBook - ePub

  Ecology

  From Individuals to Ecosystems

  • Michael Begon, Colin R. Townsend(Authors)
  • 2020(Publication Date)
  • Wiley

    (Publisher)

  Chapter 7 Life History Ecology and Evolution

  7.1 Introduction

  An organism’s life history is its lifetime pattern of growth, differentiation, storage and reproduction. In Chapter 4 , we saw something of the variety in these patterns and what their consequences may be in terms of population rates of increase. We can simply accept this variation. But in the spirit of nothing making sense except in the light of evolution (Chapter 1 ), we can go on to ask what evolutionary pressures have given rise to this variety, and what sustains it. In turn, this feeds back to an understanding of patterns in life history ecology: what types of life history are found where, and in what types of organism.

  three types of question

  There are at least three different types of question that are commonly asked. The first concerns individual life history traits. How is it that swifts, for example, usually produce clutches of three eggs, when other birds produce larger clutches and the swifts themselves are physiologically capable of doing so? Can we establish that this clutch size is ultimately the most productive – the fittest in evolutionary terms – and what is it about this particular clutch size that makes it so?

  The second question concerns links between life history traits. How is it, for example, that the ratio between age at maturity and average lifespan is often roughly constant within a group of organisms but markedly different between groups (e.g. mammals 1.3, fish 0.45)? What is the basis for the constancy within a group of related organisms? What is the basis for differences between groups?

  Thirdly, we can ask questions about links between life histories and habitats, where ‘habitat’, of course, includes other species with which a focal species coexists. Orchids, for example, produce vast numbers of tiny seeds, whereas tropical Mora

  Sign up to read

  Learn more about book
• 

  eBook - PDF

  Statistical Approaches for Hidden Variables in Ecology

  • Nathalie Peyrard, Olivier Gimenez(Authors)
  • 2022(Publication Date)
  • Wiley-ISTE

    (Publisher)

  2 Detection of Eco-Evolutionary Processes in the Wild: Evolutionary Trade-Offs Between Life History Traits Valentin J OURNÉ 1 , Sarah CUBAYNES 2 , Julien PAPAÏX 3 and Mathieu BUORO 4 1 Grenoble Alpes University, INRAE, LESSEM, Saint-Martin-d’Hères, France 2 CEFE, University of Montpellier, CNRS, EPHE-PSL University, IRD, Paul Valéry Montpellier 3 University, France 3 Biostatistique et Processus Spatiaux (BioSP), INRAE, Avignon, France 4 ECOBIOP, INRAE, Saint-Pée-sur-Nivelle, France 2.1. Context The biological lifecycle of organisms is characterized by a set of demographic traits, known as life history traits (e.g. size, growth, age at maturity, lifespan, etc.), which are often inter-related. In cases where these life history traits are positively dependent on a single limited resource, they exhibit negative correlation. If traits affect fitness components, in terms of survival and/or reproduction, then the dependency relationship is known as an evolutionary trade-off (Stearns 1989; Roff 2002; Flatt and Heyland 2011). If life history traits were independent, then individuals would simply seek to optimize each trait in order to maximize their own fitness. In reality, however, resources (time, space, energy, etc.) are limited, and must be shared, at individual level, between different traits that are essential to survival and reproduction (Metcalf 2016). While there may be environmental or genetic bases for Statistical Models for Hidden Variables in Ecology, coordinated by Nathalie PEYRARD and Olivier GIMENEZ. © ISTE Ltd 2022. Statistical Approaches for Hidden Variables in Ecology, First Edition. Nathalie Peyrard and Olivier Gimenez. © ISTE Ltd 2022. Published by ISTE Ltd and John Wiley & Sons, Inc. 28 Statistical Models for Hidden Variables in Ecology trade-off (e.g. pleiotropic effects of genes), differential resource allocation is a widely cited explanation (Flatt and Heyland 2011; Descamps et al. 2016).

  Sign up to read

  Learn more about book
• 

  eBook - PDF

  Ecology of Insects

  Concepts and Applications

  • Martin R. Speight, Mark D. Hunter, Allan D. Watt(Authors)
  • 2009(Publication Date)
  • Wiley-Blackwell

    (Publisher)

  6.4 LIFE HISTORY VARIATIONS WITH REGION As illustrated with Elatobium above, within a species’ range, the dominant life history strategy may also vary according to the geographic location of a parti- cular population, based predominantly on the local environmental conditions. For example, worker castes in the ant Trachymyrmex septentrionalis (Hymenoptera: Formicidae) differ in their mean sizes (Beshers & Traniello 1994). Colonies in Long Island, New York State, have larger individuals on average than those in Florida. It is suggested that the northerly colonies have evolved a life history strategy adapted to survive temperate winters, whereas those in the subtropical south have experienced different selection pressures and have adapted for rapid colony growth in the absence of climatic constraints. In Western Europe, the grayling butterfly, Hipparchia semele (Lepidoptera: Satyridae), shows significant regional differences in several life history features, including longevity, fec- undity, egg-laying rates, and egg size (Garcia-Barros 1992). This species feeds on grasses as a larva, and is commonly found in heathland, sand dunes, and along the edges of cliffs. In the north of the region, there is a higher concentration of egg production early in the life of the adult female, and smaller eggs are produced, relative to butterfly populations in Mediterranean areas. Adult females also live longer in the latter region. Adverse climatic conditions expected in more northerly climes mean that adult females must repro- duce faster and earlier before the shorter warm season is over. Of course, these examples describe extremes of what is likely to be a continuum of strategies where a species range is continuous, or clinal. Where a single species is necessarily split into more isolated popu- lations by natural barriers or manmade ones, demes may be generated where population characteristics may be discontinuous (Section 6.6).

  Sign up to read

  Learn more about book