Michael Doebeli
- Published in print:
- 2011
- Published Online:
- October 2017
- ISBN:
- 9780691128931
- eISBN:
- 9781400838936
- Item type:
- book
- Publisher:
- Princeton University Press
- DOI:
- 10.23943/princeton/9780691128931.001.0001
- Subject:
- Biology, Biodiversity / Conservation Biology
Understanding the mechanisms driving biological diversity remains a central problem in ecology and evolutionary biology. Traditional explanations assume that differences in selection pressures lead ...
More
Understanding the mechanisms driving biological diversity remains a central problem in ecology and evolutionary biology. Traditional explanations assume that differences in selection pressures lead to different adaptations in geographically separated locations. This book takes a different approach and explores adaptive diversification—diversification rooted in ecological interactions and frequency-dependent selection. In any ecosystem, birth and death rates of individuals are affected by interactions with other individuals. What is an advantageous phenotype therefore depends on the phenotype of other individuals, and it may often be best to be ecologically different from the majority phenotype. Such rare-type advantage is a hallmark of frequency-dependent selection and opens the scope for processes of diversification that require ecological contact rather than geographical isolation. This book investigates adaptive diversification using the mathematical framework of adaptive dynamics. Evolutionary branching is a paradigmatic feature of adaptive dynamics that serves as a basic metaphor for adaptive diversification, and the book explores the scope of evolutionary branching in many different ecological scenarios, including models of coevolution, cooperation, and cultural evolution. It also uses alternative modeling approaches. Stochastic, individual-based models are particularly useful for studying adaptive speciation in sexual populations, and partial differential equation models confirm the pervasiveness of adaptive diversification. Showing that frequency-dependent interactions are an important driver of biological diversity, the book provides a comprehensive theoretical treatment of adaptive diversification.Less
Understanding the mechanisms driving biological diversity remains a central problem in ecology and evolutionary biology. Traditional explanations assume that differences in selection pressures lead to different adaptations in geographically separated locations. This book takes a different approach and explores adaptive diversification—diversification rooted in ecological interactions and frequency-dependent selection. In any ecosystem, birth and death rates of individuals are affected by interactions with other individuals. What is an advantageous phenotype therefore depends on the phenotype of other individuals, and it may often be best to be ecologically different from the majority phenotype. Such rare-type advantage is a hallmark of frequency-dependent selection and opens the scope for processes of diversification that require ecological contact rather than geographical isolation. This book investigates adaptive diversification using the mathematical framework of adaptive dynamics. Evolutionary branching is a paradigmatic feature of adaptive dynamics that serves as a basic metaphor for adaptive diversification, and the book explores the scope of evolutionary branching in many different ecological scenarios, including models of coevolution, cooperation, and cultural evolution. It also uses alternative modeling approaches. Stochastic, individual-based models are particularly useful for studying adaptive speciation in sexual populations, and partial differential equation models confirm the pervasiveness of adaptive diversification. Showing that frequency-dependent interactions are an important driver of biological diversity, the book provides a comprehensive theoretical treatment of adaptive diversification.
Michael Doebeli
- Published in print:
- 2011
- Published Online:
- October 2017
- ISBN:
- 9780691128931
- eISBN:
- 9781400838936
- Item type:
- chapter
- Publisher:
- Princeton University Press
- DOI:
- 10.23943/princeton/9780691128931.003.0005
- Subject:
- Biology, Biodiversity / Conservation Biology
This chapter discusses adaptive diversification due to predator–prey interactions. It has long been recognized that consumption, that is, predation, can not only exert strong selection pressure on ...
More
This chapter discusses adaptive diversification due to predator–prey interactions. It has long been recognized that consumption, that is, predation, can not only exert strong selection pressure on the consumer, but also on the consumed species. However, predation has traditionally received much less attention than competition as a cause for the origin and maintenance of diversity. By using adaptive dynamics theory as well as individual-based models, the chapter then illustrates that adaptive diversification in prey species due to frequency-dependent predator–prey interactions is a theoretically plausible scenario. It also describes conditions for diversification due to predator–prey interactions in classical Lotka–Volterra models, which requires analysis of coevolutionary dynamics between two interacting species, and hence of adaptive dynamics in two-dimensional phenotype spaces.Less
This chapter discusses adaptive diversification due to predator–prey interactions. It has long been recognized that consumption, that is, predation, can not only exert strong selection pressure on the consumer, but also on the consumed species. However, predation has traditionally received much less attention than competition as a cause for the origin and maintenance of diversity. By using adaptive dynamics theory as well as individual-based models, the chapter then illustrates that adaptive diversification in prey species due to frequency-dependent predator–prey interactions is a theoretically plausible scenario. It also describes conditions for diversification due to predator–prey interactions in classical Lotka–Volterra models, which requires analysis of coevolutionary dynamics between two interacting species, and hence of adaptive dynamics in two-dimensional phenotype spaces.
Michael Doebeli
- Published in print:
- 2011
- Published Online:
- October 2017
- ISBN:
- 9780691128931
- eISBN:
- 9781400838936
- Item type:
- chapter
- Publisher:
- Princeton University Press
- DOI:
- 10.23943/princeton/9780691128931.003.0008
- Subject:
- Biology, Biodiversity / Conservation Biology
This chapter examines adaptive diversification in language and religion. The historic record contains many examples of the types of diversification occurring in these models. Diversification in ...
More
This chapter examines adaptive diversification in language and religion. The historic record contains many examples of the types of diversification occurring in these models. Diversification in languages has been rampant throughout history, and must have often occurred under substantial contact between hosts of diverging language memes. Similarly, it seems clear that religious diversification has often occurred, and continuous to occur, under conditions of substantial contact. The models illustrate that diversifying processes should be expected to operate whenever the likelihood of secession from a dominant culture increases with increasing dominance of the mainstream culture. Intuitively, it is not hard to imagine that the attractiveness of a culture diminishes as the culture becomes more dominant, dogmatic, and perhaps oppressive, and that the desire to stand out and be different increases in increasingly conformist cultures.Less
This chapter examines adaptive diversification in language and religion. The historic record contains many examples of the types of diversification occurring in these models. Diversification in languages has been rampant throughout history, and must have often occurred under substantial contact between hosts of diverging language memes. Similarly, it seems clear that religious diversification has often occurred, and continuous to occur, under conditions of substantial contact. The models illustrate that diversifying processes should be expected to operate whenever the likelihood of secession from a dominant culture increases with increasing dominance of the mainstream culture. Intuitively, it is not hard to imagine that the attractiveness of a culture diminishes as the culture becomes more dominant, dogmatic, and perhaps oppressive, and that the desire to stand out and be different increases in increasingly conformist cultures.
Michael Doebeli
- Published in print:
- 2011
- Published Online:
- October 2017
- ISBN:
- 9780691128931
- eISBN:
- 9781400838936
- Item type:
- chapter
- Publisher:
- Princeton University Press
- DOI:
- 10.23943/princeton/9780691128931.003.0006
- Subject:
- Biology, Biodiversity / Conservation Biology
This chapter focuses on adaptive diversification due to cooperative interactions. If predation has received less attention than competition as a cause for the origin and maintenance of diversity, ...
More
This chapter focuses on adaptive diversification due to cooperative interactions. If predation has received less attention than competition as a cause for the origin and maintenance of diversity, mutualistic interactions have fared even worse. There is quite a substantial theoretical literature on the ecology of mutualistic interactions, but only a few studies have investigated mutualism as a potential driver of diversification. There is of course a rather huge literature on the evolution of intraspecific cooperation, and many of these models implicitly address the problem of coexistence between cheaters and cooperators, and hence the maintenance of diversity. However, the origin of diversity in cooperative contributions has only recently been investigated. Most models of cooperation assume that cooperators make a costly contribution to a public good, which is then distributed among certain members of the population.Less
This chapter focuses on adaptive diversification due to cooperative interactions. If predation has received less attention than competition as a cause for the origin and maintenance of diversity, mutualistic interactions have fared even worse. There is quite a substantial theoretical literature on the ecology of mutualistic interactions, but only a few studies have investigated mutualism as a potential driver of diversification. There is of course a rather huge literature on the evolution of intraspecific cooperation, and many of these models implicitly address the problem of coexistence between cheaters and cooperators, and hence the maintenance of diversity. However, the origin of diversity in cooperative contributions has only recently been investigated. Most models of cooperation assume that cooperators make a costly contribution to a public good, which is then distributed among certain members of the population.
Charles F. Manski
- Published in print:
- 2019
- Published Online:
- May 2020
- ISBN:
- 9780691194738
- eISBN:
- 9780691195360
- Item type:
- chapter
- Publisher:
- Princeton University Press
- DOI:
- 10.23943/princeton/9780691194738.003.0006
- Subject:
- Economics and Finance, Econometrics
This chapter views patient care from a population health perspective. The argument for treatment variation strengthens when one considers patient care as a population health problem rather than from ...
More
This chapter views patient care from a population health perspective. The argument for treatment variation strengthens when one considers patient care as a population health problem rather than from the perspective of a clinician treating an individual patient. This chapter shows that randomly varying the treatment of patients with the same observed attributes can provide valuable error protection and information under uncertainty. That is, it may be useful to diversify treatment choice. The chapter explains that implementation of adaptive diversification may be possible in centralized health-care systems where there exists a planning entity who chooses treatments for a broad patient population.Less
This chapter views patient care from a population health perspective. The argument for treatment variation strengthens when one considers patient care as a population health problem rather than from the perspective of a clinician treating an individual patient. This chapter shows that randomly varying the treatment of patients with the same observed attributes can provide valuable error protection and information under uncertainty. That is, it may be useful to diversify treatment choice. The chapter explains that implementation of adaptive diversification may be possible in centralized health-care systems where there exists a planning entity who chooses treatments for a broad patient population.