Evolutionary Ecology, Biol 548 • Scott Nuismer (UI) • Life Sciences South 266C • Mark Dybdahl (WSU) • 269 Eastlick What is evolutionary ecology? • Historical contemporary views – Central questions – Central approaches What is evolutionary ecology, v.1? • Mayhew, P. 2006. Discovering Evolutionary Ecology. Oxford Press • “…understand diversity, how it arises, how it is maintained, and why sometimes it is not” What is evolutionary ecology, v.2? • Fox et al. 2001. Evolutionary Ecology: Concepts and Case Studies. Oxford Press. Oxford Press • Understand the nature and causes of phenotypic variation of populations and species in their natural habitat • Contemporary and historical influences on phenotypic variation • Predicting evolutionary change in a particular ecologically important traits in a specific population A brief history: the study of variation Darwin (1859) 'how the innumerable species inhabiting this world have been modified, so as to acquire that perfection of structure and coadaptation that most justly excites our admiration.’ Variation and Adaptation • Natural selection: a unifying principle to explain two things 1. the transmutation of species (“descent with modification”) 2. the adaptation of organisms to their environment A brief history: the study of variation • 1890’s: shell width of crabs has adaptive value (Weldon 1899) • Observed change in shell width that spanned samples collected before and after the construction of a breakwater in Plymouth Bay The “dawn” of adaptation research? • Despite the central role of natural selection in Darwin’s insights, there was little research on the adaptive value of phenotypic variation • Most effort was focused on the inheritance of variation. Adaptation: Variation in discrete traits • 1940’s: Ecological Genetics • Adaptive value of discrete phenotypes in nature – Controlled by few loci • Industrial melanism in moths, Kettlewell 1958 Variation in discrete traits • Evidence of natural selection inferred: – Changes in the frequency of discrete phenotypes through the life cycle – Consistency of patterns across generations – Correlations between frequencies and variation in environmental factors • Cain & Sheppard 1954 • Cepaea nemoralis: yellow/pink, banded/unbanded • Discrete color, banding traits associated with habitat Variation in continuous traits • 1970’s: Quantitative trait evolution • Continuously distributed trait values: – controlled by many loci, each of small effect – Many important traits • Life-history, behavioral, morphological, physiological Constraints and Variation • Darwin: perfect adaptation should be rare – Evolution: like building with stones that fall from a cliff • Jacob (1977): evolution uses the materials available Natural selection leads to adaptation, not perfection Constraints and Variation • Darwin: evolutionary adaptation is a function of history – Responses to selection would vary among lineages Wasps sting Termites bite Constraints and Variation • Darwin: different aspects of morphology are “tied” to one another – Selection on one trait would cause correlated changes in others that were not adaptive Constraints: reiterated • Gould & Lewontin 1979: • Criticized adaptationist thinking • Phenotypic variation also influenced by – Mutation, drift, migration – Historical events – Constraints on adaptation —‘evolvability’
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Evolutionary Ecology, Biol 548!
• Scott Nuismer (UI)!• Life Sciences South 266C!
• Mark Dybdahl (WSU) !• 269 Eastlick!
What is evolutionary ecology?!
• Historical contemporary views!– Central questions!– Central approaches!
What is evolutionary ecology, v.1?!
• Mayhew, P. 2006. Discovering Evolutionary Ecology. Oxford Press!
• “…understand diversity, how it arises, how it is maintained, and why sometimes it is not”!
What is evolutionary ecology, v.2?!
• Fox et al. 2001. Evolutionary Ecology: Concepts and Case Studies. Oxford Press. Oxford Press!
• Understand the nature and causes of phenotypic variation of populations and species in their natural habitat!
• Contemporary and historical influences on phenotypic variation!
• Predicting evolutionary change in a particular ecologically important traits in a specific population!
A brief history: the study of variation!
Darwin (1859)!'how the innumerable
species inhabiting this world have been modified, so as to acquire that perfection of structure and coadaptation that most justly excites our admiration.’!
Variation and Adaptation!
• Natural selection: a unifying principle to explain two things!
1. the transmutation of species (“descent with modification”)!
2. the adaptation of organisms to their environment!
A brief history: the study of variation!
• 1890’s: shell width of crabs has adaptive value (Weldon 1899)!
• Observed change in shell width that spanned samples collected before and after the construction of a breakwater in Plymouth Bay!
The “dawn” of adaptation research?!
• Despite the central role of natural selection in Darwin’s insights, there was little research on the adaptive value of phenotypic variation
• Most effort was focused on the inheritance of variation.
Adaptation: Variation in discrete traits!
• 1940’s: Ecological Genetics!• Adaptive value of discrete
phenotypes in nature!– Controlled by few loci!
• Industrial melanism in moths, Kettlewell 1958!
Variation in discrete traits!
• Evidence of natural selection inferred:!– Changes in the frequency of discrete
phenotypes through the life cycle!– Consistency of patterns across
generations!– Correlations between frequencies and
2. How are phenotypic variants related to fitness? !
• How does this performance vary with the environment? !
Questions about variation!
3. Constraints on adaptation?!
Central question:"Variation and adaptation!
• Understand the nature and causes of phenotypic variation of populations and species in their natural habitat!
• Contemporary and historical influences on phenotypic variation!
• Predicting evolutionary change in a particular ecologically important traits in a specific population!
What is evolutionary ecology, v.3?!
• Roughgarden 1979. Theory of Population Genetics and Evolutionary Ecology: An Introduction. MacMillan!
• The fusion of population ecology with evolutionary theory!
What is evolutionary ecology, v.3?!
• “Bringing together ecology and evolution”!
• “how do evolutionary and ecological processes affect each other?”!
• Mayhew, P. 2006. Discovering Evolutionary Ecology. Oxford Press!
evolution !ecology !
Why do we need a fusion?!
• Traditional interests: Evolution!– genetic and phenotypic
properties of populations!
Why do we need a fusion?!
• Traditional interests: Ecology!– Individual strategies to cope
with the environment!– Population abundance and
distribution!– Communities!– Ecosystems!
Historical view of theory!
Lotka 1945:!• The time scales for evolution and population
ecology are different!– “Evolutionary time” vs. “ecological time”!
• Population dynamics has been a separate pursuit from population genetics and evolution!
Fusion reiterated!Endler, J.A. Editor, Evolutionary Ecology!
– Website accessed January, 2011!
• The interplay between ecology and evolution remains comparatively neglected.!
• These cartoons of ecology and evolution reflect a fundamental gap in both subject matter and approach!
• Evolutionary Ecology: the premier journal for research on both the evolutionary influences on ecological processes and on the ecological influences on evolutionary processes.!