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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
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’!
Constraints: reiterated !• Gould & Vrba 1982:
Adaptationist hypotheses should be tested rigorously!
• As association between a trait and a function does not demonstrate that the trait evolved for that function.!
• Traits could be co-opted for new function without further adaptation !
• Ex. Radial sesamoid bone and Panda’s thumb!
Questions about variation!
1.! Is phenotypic variation genetically or environmentally determined? !
Questions about variation!
2. How are phenotypic variants related to fitness? !
• individual performance: ability to garner resources, avoid predators, find mates, reproduce?!
Questions about variation!
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.!
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Why merge ecology and evolution?!• Time scales may not be different!
– Gene substitution can occur in the same time needed by a population to attain equilibrium abundance!
• Population dynamic parameters are not fixed!– Parameters characterizing population growth change by
natural selection during the course of population growth!• The relationship between Ecology and Evolution is both
intimate and fundamental !– Variation in habitats and climates can have a profound
effect on both ecological and evolutionary processes!
Ecology: traditional interests?!
• Individual level:!– Behavioral ecology!– Physiological ecology!
• Optimal phenotypes: e.g.!• Plant architecture!• Foraging!• Life history!
EE thinking:!• Discovery of optimization
principles that correctly predicts evolution!
Ecology: traditional interests?!
• Population level:!– Population ecology!
EE thinking:!• Evolutionary processes acting at
population level: e.g.!• Genetic models of N.S. and
evolution!
• Population dynamics!– Single species or two-
species interactions!– abundance, growth,
regulation!
Ecology: traditional interests?!
• Community/ecosystem level:!– Community ecology!– Ecosystem ecology!
EE thinking:!! !???!
• Community dynamics!• Flow of energy, materials
between compartments!– Species coexistence!– abundance, growth,
regulation!
http://www.webpages.uidaho.edu/~snuismer/Nuismer_Lab/548.htm!
• Course materials!• Course syllabus!• Lectures!• Resources!
Syllabus Overview!• Graduate seminar format!• Lectures: Thursdays:!
– Foundations of Evolutionary Ecology!
– Specific topics in Evolutionary Ecology!
• Problem solving/Discussion: Tuesdays!
Problem solving/Data analysis!
• Discussions led by 2-3 students !– randomly selected at
the beginning of each!
x lx mx 0 1 0 1 0.7 0.2 2 0.4 0.5 3 0.2 0.7 4 0.1 .04
Reading/Discussion!• Recent papers from
the primary literature!• Citations provided !
– PDF format through the university library system!
• Discussions led by 2-3 students !– randomly selected at
the beginning of each!
Research paper: a review !Format: Trends in Ecology
and Evolution!1. Select a topic and obtain
approval from editors (i.e. the instructors)!
2. Write and submit a pre-proposal: Is the topic is timely and exciting?!
3. Write and submit an outline!
4. complete the review !
Presentation: your research paper topic!
• Last week of classes!• 15-20 minutes!
Grading!
• Problem solving/Discussion: !100 pts!• Research paper: ! ! !300 pts!• Presentation: ! ! ! !100 pts!
Foundation topics!
Specific topics! Other emerging topics in "Evolutionary Ecology!
• Adaptation to anthropogenic change!• Community genetics!• Evolutionary demography!• Macroecology!
• ?????!
Discussion Jan 18:"What is Evolutionary Ecology?!
• Traditional view of EE: understanding variation and adaptation!– Pigliucci, M. and J. Kaplan. 2000. The fall and rise of
Dr Pangloss: adaptationism and the Spandrels paper 20 years later. TREE 15:66-70.!
• Merging ecology and evolution: !– Thompson, J. 1998. Rapid evolution as an ecological
process. TREE 13:329-332!
• Roughgarden, J. 1979. Theory of Population Genetics and Evolutionary Ecology: An Introduction. MacMillan!
• Mayhew, P. 2006. Discovering Evolutionary Ecology. Oxford Press!• Fox, C.W., D.A. Roff, and D.J. Fairbairn. 2001. Evolutionary Ecology: Concepts
and Case Studies. Oxford Press!• Gould S.J. and R.C. Lewontin. 1979 The Spandrels of San Marco and the
Panglossian paradigm: a critique of the adaptationist programme. Proc. R. Soc. Lond. B 205:581-598!
• Jacob, F. 1977. Evolution and tinkering. Science 196:1161-1166!• Pigliucci, M. and J. Kaplan. 2000. The fall and rise of Dr Pangloss:
adaptationism and the Spandrels paper 20 years later. Trends in Ecology and Evolugion 15:66-70.!
• Schlichting, C.D. and M. Pigliucci. 1998. Ch. 1 in Phenotypic Evolution. Sinauer Assoc.!
