Showing papers by "Donald L. DeAngelis published in 1986"
Book•
01 Apr 1986
TL;DR: This chapter discusses the evolution of Mutualistic Communities, a model of multi-Species, Multi-patch Systems with Competition and Mutalism, and the role of positive feedback in this evolution.
Abstract: 1. Introduction.- 1.1 Homeostasis.- 1.2 Positive Feedback.- 1.3 Ecological Systems with Positive Feedback.- 1.4 Generalization 1: Increasing Complexity.- 1.5 Generalization 2: Accelerating Change.- 1.6 Generalization 3: Threshold Effects.- 1.7 Generalization 4: Fragility of Complex Systems.- 1.8 Summary and Conclusions.- 2. The Mathematics of Positive Feedback.- 2.1 Graphical Analysis of a Simple Dynamic Positive Feedback System.- 2.2 A System of Two Mutualists.- 2.3 A System of Two Competitors.- 2.4 Mathematical Analysis of Positive Feedback.- 2.5 Summary and Conclusions.- 3. Physical Systems.- 3.1 The Life History of a Star.- 3.2 Geophysical Systems.- 3.3 Autocatalysis in Chemical Systems.- 3.4 Summary and Conclusions.- 4. Evolutionary Processes.- 4.1 Early Evolution of Life.- 4.2 Evolution at the Species Level.- 4.3 Coevolution.- 4.4 Summary and Conclusions.- 5. Organisms Physiology and Behaviour.- 5.1 Destructive Positive Feedback.- 5.2 Biochemical Processes in Cells and Organisms.- 5.3 Feeding and Drinking Behavior.- 5.4 Sleep.- 5.5 Movement and Motor-Sensory Relationships.- 5.6 Mind-Body Relationship.- 5.7 Summary and Conclusions.- 6. Resource Utilization by Organisms.- 6.1 Energy Allocation Tactics.- 6.2 Territorial Defense Strategies.- 6.3 Chemical Defense Strategies.- 6.4 Growth Rate Strategy.- 6.5 Summary and Conclusions.- 7. Social Behavior.- 7.1 Evolution of r- and K-strategies.- 7.2 Development of Social Strategies.- 7.3 Mating and Reproduction.- 7.4 Population Models Incorporating Sexual Reproduction.- 7.5 Small Group Dynamics.- 7.6 Castes In Insect Societies.- 7.7 Dominance Within Groups.- 7.8 Models of Group Formation and Size.- 7.9 The Schooling of Fish.- 7.10 Social Interactions and Game Theory.- 7.11 Summary and Conclusions.- 8. Mutualistic and Competitive Systems.- 8.1 Dynamics of Mutualistic Communities.- 8.2 Limits to Mutual Benefaction.- 8.3 Multi-Species Mutualism.- 8.4 Models of the Evolution of Mutualism.- 8.5 Isolation and Obligate Mutualism.- 8.6 Limited Competition.- 8.7 Summary and Conclusions.- 9. Age-Structured Populations.- 9.1 Age Structure.- 9.2 Leslie Matrices.- 9.3 Compensatory Leslie Matrices.- 9.4 Interacting Populations.- 9.5 Coexistence of Two Interacting Populations.- 9.6 Other Compensatory Models.- 9.7 Life-History Strategies.- 9.8 Intrinsic Rate of Increase.- 9.9 Reproductive Strategies.- 9.10 Summary and Conclusions.- 10. Spatially Heterogeneous Systems: Islands and Patchy Regions.- 10.1 Classical Theory of Island Biogeography.- 10.2 Island Clusters.- 10.3 Insular Reserves.- 10.4 Modeling the Patchy System.- 10.5 A Single Species in a Patchy Region.- 10.6 Time to Extinction on a Patch.- 10.7 Persistence of a Species in a Two-Patch Environment.- 10.8 Stability of a Single-Species, Two-Patch System.- 10.9 Persistence of a Species in an N-Patch Environment.- 10.10 Multi-Species, Multi-patch Systems with Competition and Mutalism.- 10.11 Persistence of a Species in a Two-Species, Two-Patch Environment.- 10.12 Persistence of a Species in an L-Species, iV-Patch Environment.- 10.13 Stability of a Two-Species, Two-Patch Model.- 10.14 Stability of an L-Species, iV-Patch Model.- 10.15 Relationship Between Reserve Design and Species Persistence.- 10.16 Summary and Conclusions.- 11. Spatially Heterogeneous Ecosystems: Pattern Formation.- 11.1 Spontaneous Emergence of Spatial Patterns.- 11.2 Diffusion Model.- 11.3 Pattern Formation Through Instability.- 11.4 Congregation of Colonial Organisms.- 11.5 Boundary Formation by Competition.- 11.6 Summary and Conclusions.- 12. Disease and Pest Outbreaks.- 12.1 Physiological Effects in the Host Species.- 12.2 Mutualistic Interactions of more than one Pathogenic Agent.- 12.3 Models of a Directly Communicated Disease or Parasite.- 12.4 Effects of Spatial Heterogeneity on Disease Outbreak Threshold Conditions.- 12.5 Design of Immunization Programs.- 12.6 Shape of the Contagion Rate Function.- 12.7 Comparison with other Spatially Heterogeneous Models.- 12.8 Host-Vector Models.- 12.9 Summary and Conclusions.- 13. The Ecosystem and Succession.- 13.1 The Ecosystem.- 13.2 Succession as a Positive Feedback Process.- 13.3 A Clementsian Model.- 13.4 Markov Chain Models.- 13.5 A Model of a Fire-Dependent System.- 13.6 Positive Feedback Loops in Ecosystems.- 13.7 Nutrient Cycling.- 13.8 Selection on the Community or Ecosystem Level.- 13.9 Summary and Conclusions.- Appendices.- Appendix A: Positive Linear Systems.- Appendix B: Stability of Positive Feedback Systems.- Appendix C: Stability of Discrete-Time Systems.- Appendix D: Positive Equilibria and Stability.- Appendix E: Comparative Statics of Positive Feedback Systems.- Appendix F: Similarity Transforms.- Appendix G: Bounds on the Roots of a Positive Linear System.- Appendix H: Relationship Between Positive Linear System Stability Criteria and the Routh-Hurwitz Criteria.- References.- Author Index.
207 citations
TL;DR: A theoretical and computer-simulation model shows how biomass and nutrient interactions can give rise to these grazing responses, and provides a plausible mechanism for explaining changes in primary productivity that is consistent with empirical data.
Abstract: Many laboratory and field studies suggest that heavy grazing decreases plant productivity, whereas light grazing may promote increases in comparison with ungrazed controls. A theoretical and computer-simulation model shows how biomass and nutrient interactions can give rise to these grazing responses. The recycling rates of limiting nutrients can be regulated nonlinearly by the grazer. This provides a plausible mechanism for explaining changes in primary productivity that are consistent with empirical data.
55 citations
01 Jan 1986
TL;DR: Until recent times, the periodic irruptions of infectious diseases have been significant factors in the lives of humans and in the history of civilized society but the increased control of human infectious disease has not lessened the importance of studying and understanding infectious diseases.
Abstract: Until recent times, the periodic irruptions of infectious diseases have been significant factors in the lives of humans and in the history of civilized society. Today many of the serious infectious diseases of humankind have been controlled. However, the increased control of human infectious disease has not lessened the importance of studying and understanding infectious diseases, because agricultural crops as well as forest resources are continually damaged by outbreaks of pests and disease. Strategies for their elimination or control are urgently needed.
5 citations
01 Jan 1986
TL;DR: This work states that when a model is put into explicit mathematical form, it can be analyzed to predict the effect on all parts of the system of external intervention on any single part.
Abstract: Concomitant with the cybernetics revolution of the past half century has been the rapid development of mathematical modeling in the biological and ecological sciences, a methodology now firmly established. A model may be defined as an abstract description of the real world, a simple representation of more complex forms, processes, and functions of physical phenomena or ideas (Rubinstein, 1975). Models have aided in the understanding of ecological systems. When a model is put into explicit mathematical form, it can be analyzed to predict the effect on all parts of the system of external intervention on any single part.
5 citations
01 Jan 1986
TL;DR: Any detailed description of population dynamics must take the age- dependent nature of these variables into account.
Abstract: Life, in part, is a process of aging; individuals are born, they mature, and at some point they die. The aging process has a direct effect on individual probabilities of survival and reproductive activity, as well as on total population size. For example, fecundity is zero until the age of reproductive maturity; it then increases and remains high through adulthood, finally declining in old age. Mortality, on the other hand, is usually high in the very young and very old individuals, and lower for adults. Any detailed description of population dynamics must take the age- dependent nature of these variables into account.
4 citations
01 Jan 1986
TL;DR: The simplest and most obvious positive feedback interaction between species is mutualism, which arises when mutualists mediate competitive or predator-prey interactions.
Abstract: The simplest and most obvious positive feedback interaction between species is mutualism. Direct interspecies mutualism can result from a multitude of interactions involving dispersal, shelter, nutrient cycling, energy provision and reproduction (Boucher et al., 1982; Faegri and Van der Pijl, 1966; Heinrich and Raven, 1972; Muscatine and Porter, 1977; Whittaker, 1975; Howe, 1977; Temple, 1977). Mutualistic interactions also arise when mutualists mediate competitive or predator-prey interactions (Wright, 1973; Janzen, 1969; Addicot, 1979; Messina, 1981; Osman and Haugsness, 1981; Heithaus et al., 1980).
4 citations
01 Jan 1986
TL;DR: In this paper, the authors considered not only interactions among species, but also interactions between species and their physical and chemical environment, therefore involving such factors as energy flow, nutrient cycles, soil conditions, and microclimate.
Abstract: Up to this point, the types of positive feedback considered have involved single species or communities of species. The ecosystem, however, includes not only interactions among species, but also interactions between species and their physical and chemical environment, therefore involving such factors as energy flow, nutrient cycles, soil conditions, and microclimate.
1 citations