Organism Behavior and Fitness

7 Key excerpts on "Organism Behavior and Fitness"

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  The Study of Behavior

  Organization, Methods, and Principles

  • Jerry A. Hogan(Author)
  • 2017(Publication Date)
  • Cambridge University Press

    (Publisher)

  The function of much behavior is fairly obvious (eating, drinking, sex, escape, care for young), but even with such obvious cases, the possible function of aspects of these behaviors needs investigation. I begin by discussing the concept of fitness and then continue with examples of 274 The Study of Behavior studies of the primary functions of behavior: feeding, defense, and reproduction. I conclude with a discussion of situations in which the primary functions of behavior interfere with each other or are condi- tional on the behavior of other individuals. I will be emphasizing empirical studies and the methods used. The nature of adaptation and selection are considered in Chapter 10. T H E C O N C E P T O F F I T N E S S Fitness is an important concept for evolution, because, without differ- ential fitness of entities in a population, evolution cannot occur! But fitness is a slippery concept. It is a concept like homeostasis and canalization: it is defined by its effects. It is one of those concepts that everyone thinks he/she understands, but then finds it difficult to specify exactly in a particular situation. A typical textbook definition of fitness is the measure of an individual’s success in passing on copies of its genes to future generations. But fitness can be defined with respect to the genotype or phenotype of a trait or an individual or even a group; it can have two or three components (viability, mating success, fecund- ity); it can be considered a property of an individual or of a class of individuals (average value of the group); it can be absolute or relative; it can be direct or indirect or inclusive; and individuals with identical genotypes may have different fitnesses depending on the environ- ments with which they have interacted during development. Also, how many generations need to be considered? The next? Two? Many? Sober (2001) and Orr (2009) discuss most of these issues.

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  Ecological Learning Theory

  • Graham Davey(Author)
  • 2018(Publication Date)
  • Taylor & Francis

    (Publisher)

  Chapter eight

  Behavioral ecology

  Living organisms are usually faced with a number of competing demands during their lifetime. Generally, these demands extend to finding food, avoiding predators, securing a sexual partner, and so on. Coping efficiently with these demands has the consequence of increasing the likelihood that the genes of that organism will survive and propagate in future generations. This in turn insures that many of the attributes possessed by that organism for coping with these demands will also be passed on to future generations if they are genetically encoded. The implication of this process is that contemporary species of animals are likely to be those which have coped most effectively with this optimality problem, and are thus likely to possess relatively optimal behavioral and psychological processes for dealing with their life’s problems. Argued in this way, optimality can be seen as a general constraint that impinges on most living organisms: dealing efficiently with the acquisition of food leaves more time to be alert to predators, and so on. There are at least two ways of going about tackling these ideas as far as we are concerned in this volume. First, we can work out mathematically what might be the optimal solution to a particular problem that the animal faces (such as choosing when to leave one food source in order to investigate others), and see if the animal’s behavior does approximate this optimal solution. Second, we would be particularly interested in the role that learning plays in achieving optimal performance, and what kinds of mechanisms underlie this learning.

  Optimality models

  MacArthur and Pianka (1966) were probably the first to introduce the idea that in order to maximize its contribution to the gene pool an animal is faced with an optimization problem. For example, in relation, say, to feeding, animals should be attempting to obtain the maximum amount of food per unit time. This is not just sheer gluttony, nor just a safeguard against any uncertainty in the future food stock; an efficient feeder can allocate relatively more time to other biologically important functions than an inefficient feeder. The kinds of optimality problems an animal is likely to encounter are usually choice problems.

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  Sociobiology: Beyond Nature/nurture?

  Reports, Definitions And Debate

  • George W Barlow, James Silverberg, Frank B Livingstone(Authors)
  • 2019(Publication Date)
  • Taylor & Francis

    (Publisher)

  Part 3The Organism in Its Environment Passage contains an image

  5.Ecological Determinism and Sociobiology

  Stephen T. Emlen

  The field of sociobiology has made major advances and attracted widespread attention during its short decade of existence as a theoretical and predictive science. When one steps back and examines the field, it becomes apparent that research is progressing along two separate, but interrelated, frontiers (Fig. 1 ).

  The first is concerned primarily with describing the types of behavioral interactions that occur between organisms living within the confines of a particular society. Building upon the evolutionary tenet of natural selection, this frontier attempts to better understand such aspects of social behavior as dominance and submissive interactions, male and female strategies of parental investment and mate selection, parent-offspring interactions and conflict, differential behavior toward members versus “outsiders” of a group, preferential interactions with kin as opposed to nonkin (nepotism), etc. (Fig. 2 ). Some of the recent developments on this frontier have included interpretations of current human behavior in terms of its probable adaptiveness during our recent evolutionary past, and predictions of behavioral interactions based upon the recent expansion of the theory of individual natural selection to encompass kin (Hamilton 1964a, 1964b; Trivers 1974; West-Eberhard 1975).

  It is this frontier of sociobiology that has attracted wide attention and become the focus of heated debate (Allen et al. 1975; Allen et al. 1976; Wade 1976; Wilson 1976).

  Evolution is basically a selfish doctrine, preaching that the individual that maximizes its own welfare and reproduction relative to others will gain the selective edge --- by leaving more descendants who, themselves, carry the same behavioral traits. If the basis of a particular human behavior is considered to be largely genetically determined,

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  Arguing for Evolution

  An Encyclopedia for Understanding Science

  • Sehoya H. Cotner, Randy Moore(Authors)
  • 2011(Publication Date)
  • Greenwood

    (Publisher)

  Regardless, behavior is heritable, and as a result, can be evaluated evolutionarily. a direct fitness benefit, while one that increases the survival and reproduc- tion of the individual’s relatives provides an indirect fitness benefit. The combination of fitness-enhancing features, direct and indirect, combines to form an individual’s inclusive fitness. Organisms Exhibit Behaviors That Increase Their Chances of Survival Examples that fulfill this prediction abound! A few that have received much study include the following: Tropic or Taxic Behavior Tropic (or taxic) behaviors include movement in response to light (pho- totaxis), touch (thigmotaxis), and a current (rheotropism). Phototaxis has 138 Arguing for Evolution been documented in essentially all taxa from prokaryotes to chordates. Many zooplankton exhibit diel vertical migration (DVM), whereby they move up or down in the water column to—in most cases—maximize food availability while minimizing predation risk. While movement of the crus- tacean Daphnia is often triggered by light, some strains exhibit positive phototaxis (i.e., movement toward light), some exhibit negative phototaxis (i.e., movement away from light), and some are both positively and nega- tively influenced by light. Migration Migratory feats have long impressed evolutionary biologists. The spiny lobster is noted for single-file processions of dozens of lobsters in search of spawning grounds. Annually, millions of monarch butterflies fly over 3,000 kilometers from their overwintering grounds in Mexico to breeding areas in the temperate United States and Canada (Figure 7.1). The life cycle of the European eel involves spawning in the Sargasso Sea and eventually re- turning to freshwaters of Europe, a migratory accomplishment that can take up to a year and span thousands of kilometers.

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  Biology

  Concepts and Applications

  • Cecie Starr, Christine Evers, Lisa Starr, , Cecie Starr, Christine Evers, Lisa Starr(Authors)
  • 2017(Publication Date)
  • Cengage Learning EMEA

    (Publisher)

  Copyright 2018 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. WCN 02-300 697 Core Concepts Animal Behavior Interactions among the components of a biological system give rise to complex properties. Genes and epigenetic mechanisms are the basis of innate (inherited) behaviors and the capacity for learning through experience. Natural selection acts on these traits, so it shapes behaviors as well as their timing and coordination. A population’s overall survival depends on communication and cooperation among its members, and is influenced by individual behavior. Adaptation of organisms to a variety of environments has resulted in diverse structures and physiological processes. Many animal behaviors occur in response to environmental cues and interactions with other organisms. Different species communicate information via visual, audible, tactile, electrical, or chemical signals that affect the behavior of other organisms. Genetic variation in these traits allows them to evolve under selection. The continuity of life arises from and depends on genetic information in DNA. Behavioral traits, like other traits, have a basis in genes. When animals reproduce sexually, they pass about half of their alleles to offspring. Alleles underlying behaviors that increase the chances of survival of offspring (or of close relatives) are adaptive, so they are passed preferentially to successive generations. Links to Earlier Concepts This chapter builds on your knowledge of sensory and endocrine systems (Chapters 30, 31). You will revisit pheromones (30.3) and learn about additional effects of the hormone oxytocin (31.3). Be sure that you understand the concepts of sexual selection (17.5) and adaptation (16.2). The chapter has many examples of scientific experiments (1.5, 1.6). 39 A male tungara frog inflates his vocal sac to make his species-specific mating call. Female frogs are attracted by the sound of this call.

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  Human Evolution

  An Introduction to Man's Adaptations

  • Bernard Campbell(Author)
  • 2017(Publication Date)
  • Routledge

    (Publisher)

  X. Sociobiology and Human Behavior

  Sociobiology, the science of the biology of social behavior, is an important and growing branch of biology that is of particular interest to us since we are a very social species. The science, with its roots in the study of social insects, is concerned with the behavior of all social animals from insects to humans. Its origin as a new science can be traced to the concept of inclusive fitness, first discussed by W. D. Hamilton in 1964.

  The concept implies that the “Darwinian fitness” of an individual not only includes its own reproductive success but that of its relatives, which share the individual’s genes. It is, as it were, the particular packages of genes that are being selected rather than particular individuals. This became clear from the study of social insects such as bees. In this group of insects, because of their unusual genetics with haploid males (i.e., males carry only one-half the normal diploid gene complement, so that the nucleus of the cells does not undergo meiosis in the production of gametes), the daughters inherit a full set of their father’s genes as compared with the usual 50% of their diploid mother’s genes. This means that since each worker bee shares (on average) 75% of its genes with its siblings (50% from having the same father and 25% from having the same mother), it pays it to work for the survival of its siblings as much as (in fact more than) for its own putative offspring, were it to have any, who would carry only 50% of its genes.

  Similarly, if a bird giving a warning cry can thus protect a number of individuals that share its genes, the gain in survival of its genes may be greater than the loss that would occur if it was killed by a predator. In practice, the selective advantage of an individual assisting a relative in this or any other way will depend on three factors: the risk to its own fitness, the benefit to the relative or relatives, and the degree of related-ness of each relative. We find that on this basis we can account for the selection of what looks like altruistic behavior in close-knit social groups where individuals are closely related.

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  Ecology in Action

  • Fred D. Singer(Author)
  • 2016(Publication Date)
  • Cambridge University Press

    (Publisher)

  In our current society, we are immersed in a much larger sea of anonymity than hunter-gatherers, yet our technology, for better or for worse, has created a vast social network that allows people who have never met to evaluate each other. Though it is highly prone to error, this knowledge may be one avenue for us to escape the “ tragedy of the commons. ” SUMMARY As with all biological processes, animal behavior is subject to the action of natural selection, favoring individuals that behave in ways that maximize their fi tness. If applied to humans, natural selection could lead to the scenario depicted by the “ tragedy of the commons ” in which selection favors humans who are greedy and exploitative, behaving in ways that improve their own welfare at the expense of the general good. But there are other alternatives to this grim picture that come into play when we appreciate the complex interactions between natural selection and animal behavior. Natural selection operates on behavioral processes that promote individual survival and, ultimately, individual reproductive success. Behavioral ecologists measure the costs and bene fi ts of alternative types of behavior to gain an understanding of basic behavioral processes such as territory defense, foraging, and mating. This cost – bene fi t approach allows quantitative predic-tions of behavior tightly tied to fi tness, such as how long to guard a mate, or how long to forage at a particular location before moving on. Both physiological factors, such as the need to keep eggs warm, and ecological factors, such as the spatial distribution of resources, can in fl uence the evolution of mating systems. Even within species, mating systems may vary in relation to the distribution or abundance of resources. In many species, individuals cooperate with each other in procuring food or defending against predators.

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