Author: H N. CominsPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The spatial dynamics of host-parasitoid systems
Author: H N. CominsThe Spatial and Temporal Dynamics of Host-Parasitoid Interactions
Author: Michael HassellPublisher: OUP Oxford
ISBN: 0191588407
Category : Science
Languages : en
Pages : 214
Book Description
This book examines our current understanding of the population dynamics of one kind of interaction - that between insect parasitoids and their hosts. Parasitoids are amongst the most abundant of all animals, and make up about 10% or more of metazoan species. Almost no insect species escape their attack. Host-parasitoid interactions were first modelled over fifty years ago, but for many years there was little good empirical information on the important factors that affect host and parasitoid populations. The models were very simple, and their predictions rather divorced from the complexity of what was visible in the field. Now, better data is available on many components of host-parasitoid systems, from field observations and laboratory and field experiments, and this allows a much closer correspondence between models and data. In particular, the past twenty years have seen major advances in our understanding of how host-parasitoid interactions are influenced by spatial processes, by age-structure effects, and by competition from additional host and parasitoid species. The result is a body of theory that makes direct contact with real systems in the field, and provides us with a detailed understanding of what underpins a whole area of population dynamics. In this book, Michael P Hassell pulls the theory and field data together to present an elegant illustration of the way in which ecological studies advance.
The Spatial and Temporal Dynamics of Host-parasitoid Interactions
Author: Michael Patrick HassellPublisher: Oxford University Press on Demand
ISBN: 9780198540892
Category : Medical
Languages : en
Pages : 200
Book Description
This book examines our current understanding of the population dynamics of one kind of interaction--that between insect parasitoids and their hosts. Parasitoids are amongst the most abundant of all animals, and make up about 10% or more of metazoan species. Almost no insect species escape their attack. Host-parasitoid interactions were first modelled over fifty years ago, but for many years there was little good empirical information on the important factors that affect host and parasitoid populations. The models were very simple, and their predictions rather divorced from the complexity of what was visible in the field. Now, better data is available on many components of host-parasitoid systems, from field observations and laboratory and field experiments, and this allows a much closer correspondence between models and data. In particular, the past twenty years have seen major advances in our understanding of how host-parasitoid interactions are influenced by spatial processes, by age-structure effects, and by competition from additional host and parasitoid species. The result is a body of theory that makes direct contact with real systems in the field, and provides us with a detailed understanding of what underpins a whole area of population dynamics. In this book, Michael P. Hassell pulls the theory and field data together to present an elegant illustration of the way in which ecological studies advance.
Spatial Dynamics of a Host-parasitoid Community
Author: Brian Henry Van HezewijkPublisher:
ISBN:
Category : Gall midges
Languages : en
Pages : 354
Book Description
Spatial Ecology
Author: David TilmanPublisher: Princeton University Press
ISBN: 069118836X
Category : Science
Languages : en
Pages : 368
Book Description
Spatial Ecology addresses the fundamental effects of space on the dynamics of individual species and on the structure, dynamics, diversity, and stability of multispecies communities. Although the ecological world is unavoidably spatial, there have been few attempts to determine how explicit considerations of space may alter the predictions of ecological models, or what insights it may give into the causes of broad-scale ecological patterns. As this book demonstrates, the spatial structure of a habitat can fundamentally alter both the qualitative and quantitative dynamics and outcomes of ecological processes. Spatial Ecology highlights the importance of space to five topical areas: stability, patterns of diversity, invasions, coexistence, and pattern generation. It illustrates both the diversity of approaches used to study spatial ecology and the underlying similarities of these approaches. Over twenty contributors address issues ranging from the persistence of endangered species, to the maintenance of biodiversity, to the dynamics of hosts and their parasitoids, to disease dynamics, multispecies competition, population genetics, and fundamental processes relevant to all these cases. There have been many recent advances in our understanding of the influence of spatially explicit processes on individual species and on multispecies communities. This book synthesizes these advances, shows the limitations of traditional, non-spatial approaches, and offers a variety of new approaches to spatial ecology that should stimulate ecological research.
The Population Dynamics of Host-host-parasitoid System
Author: Abigail Nyree Jane CaseyPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Parasitoid Population Biology
Author: Michael E. HochbergPublisher: Princeton University Press
ISBN: 0691230897
Category : Science
Languages : en
Pages : 381
Book Description
Extraordinary in the diversity of their lifestyles, insect parasitoids have become extremely important study organisms in the field of population biology, and they are the most frequently used agents in the biological control of insect pests. This book presents the ideas of seventeen international specialists, providing the reader not only with an overview but also with lively discussions of the most salient questions pertaining to the field today and prescriptions for avenues of future research. After a general introduction, the book divides into three main sections: population dynamics, population diversity, and population applications. The first section covers gaps in our knowledge in parasitoid behavior, parasitoid persistence, and how space and landscape affect dynamics. The contributions on population diversity consider how evolution has molded parasitoid populations and communities. The final section calls for novel approaches toward resolving the enigma of success in biological control and questions why parasitoids have been largely neglected in conservation biology. Parasitoid Population Biology will likely be an important influence on research well into the twenty-first century and will provoke discussion amongst parasitoid biologists and population biologists. In addition to the editors, the contributors are Carlos Bernstein, Jacques Brodeur, Jerome Casas, H.C.J. Godfray, Susan Harrison, Alan Hastings, Bradford A. Hawkins, George E. Heimpel, Marcel Holyoak, Nick Mills, Bernard D. Roitberg, Jens Roland, Michael R. Strand, Teja Tscharntke, and Minus van Baalen.
Mathematical Analysis of Host-parasitoid Dynamics
Author: Kelsey MarcinkoPublisher:
ISBN:
Category :
Languages : en
Pages : 158
Book Description
Host and parasitoid systems are of great interest to ecologists, both because of the global prevalence of insect parasitoids and the impact of parasitoids in regulating their hosts. The direct connection between parasitized hosts and parasitoid offspring leads to simple and specific modeling assumptions. The discrete-time models used for host-parasitoid interactions are also sometimes used for more general predator-prey systems or even to describe consumer-resource dynamics in the broadest sense. In this dissertation, I examine some of the specific building blocks involved in formulation of host-parasitoid models and determine the impacts of these assumptions. I begin with an introduction that includes biological context and a brief overview of the mathematical frameworks used in my work. Next, I present a systematic comparison and analysis of four discrete-time, host-parasitoid models. For each model, I specify that density-dependent effects occur prior to parasitism in the life cycle of the host. I compare density-dependent growth functions arising from the Beverton-Holt and Ricker maps, as well as parasitism functions assuming either a Poisson or negative binomial distribution for parasitoid attacks. I show that overcompensatory density-dependence leads to period-doubling bifurcations, which may be supercritical or subcritical. Stronger parasitism from the Poisson distribution leads to loss of stability of the coexistence equilibrium through a Neimark--Sacker bifurcation, resulting in population cycles. My analytic results also revealed dynamics for one of my models that were previously undetected by authors who conducted a numerical investigation. In this section, I also emphasize the importance of clearly presenting biological assumptions that are inherent to the structure of a discrete-time model in order to promote communication and broader understanding. Climate change has created new and evolving environmental conditions, impacting all species, including hosts and parasitoids. Building on my work with nonspatial host-parasitoid models, I next consider integrodifference equation (IDE) models of host-parasitoid systems to incorporate space and climate-driven shifts in habitats. I describe and analyze three IDE models of host--parasitoid systems to determine criteria for coexistence of the host and parasitoid. Specifically, I determine the critical habitat speed, beyond which the parasitoid cannot survive. By comparing the results from three IDE models, I investigate the impacts of assumptions that reduce the system to a single-species model. I also compare critical speeds predicted by a spatially-implicit difference-equation model with critical speeds determined from numerical simulations of the IDE system. The spatially-implicit model uses approximations for the dominant eigenvalue of an integral operator. The classic methods to approximate the dominant eigenvalue for IDE systems do not perform well for asymmetric kernels, including those that are present in shifting-habitat IDE models. Therefore, I compare several methods for approximating dominant eigenvalues and ultimately conclude that geometric symmetrization and iterated geometric symmetrization give the best estimates of the parasitoid critical speed.
Author: M P. Hassell
Author: Roy Werner Wright