Download The structure of community ecology - Botany, UBC

The structure of community ecology
Mark Vellend
Departments of Botany & Zoology
Biodiversity Research Centre
University of British Columbia
Is community ecology a mess?
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…with a key difference in how process is treated
Patterns we
want to
understand
Population
Genetics
Community
Ecology
Diversity and
composition of
alleles/genotypes
Diversity and
composition of
species
Processes to Mutation
explain
Drift
patterns
Migration
Selection
Competition
Predation
Niches
Neutrality
Island biogeography
Resource-use trade-offs
Colonization-competition trade-offs
Disturbance
Productivity
Evolutionary history
Etc.
But is the difference real or necessary?
Patterns we
want to
understand
Population
Genetics
Community
Ecology
Diversity and
composition of
alleles/genotypes
Diversity and
composition of
species
Processes to Mutation
explain
Drift
patterns
Migration
Selection
Speciation
Drift
Dispersal
Selection
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Question on Ecology 101 final exam:
What processes influence species
composition and diversity?
Answer:
Question on Evolution 101 final exam:
What processes influence genetic variation?
Answer:
Mutation
Drift
Migration
Selection
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Processes that influence community
composition and diversity
Speciation:
The creation of new species.
Drift:
Random changes in the relative frequencies of species.
Dispersal:
Movement of organisms/propagules among communities.
Selection:
Deterministic differential survival or reproduction of species.
THE LAST 40
YEARS OF
COMMUNITY
ECOLOGY
The MacArthur school (Marlboro Circle)
Simple, general, deterministic models
Compare equilibrium to data – draw inferences
Island Biogeography
That’s fraught with pattern-process problems
Most of the world is not at
equilibrium most of the time
(Strong, Simberloff criticize “assembly rules”)
SELECTION
Lawton’s
“traditional”
Manipulative
field experiments
community ecology
Patch
dynamics and
disequilibrium
Neutral theory:
the ultimate null
model?
DRIFT
Better “null” models
for community
assembly studies
Spatial ecology
DISPERSAL
Niche-neutral
reconciliation
Metacommunities
Experiments often give good
answers to trivial questions, are
system specific and local
Back to history and
geography
Macroecology
SPECIATION
(Ricklefs’ regional effects)
Better inferential
tools
Metabolic theory
(community ecology?)
(ML, Bayes)
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Conceptual umbrella
Key contribution
Competition theory
Experimental ecology
SELECTION
Regional & historical effects
SPECIATION
(+ DISPERSAL)
Neutral theory
DRIFT
Metacommunities
DISPERSAL
The Structure of Community Ecology
Morin (1999)
Community Ecology
Putman (1993)
Community Ecology
I: Communities,
Patterns and Processes:
Competition I, Competition II
Predation I, Predation II
Food Webs
Mutualisms
Indirect Effects
II: Factors Influencing Interactions:
Temporal Patterns
Habitat Selection
Spatial Dynamics
III: Large Scale Phenomena:
Causes and Consequences of Diversity
Succession
Applied Community Ecology
Ecological communities - definitions
and a search for pattern.
Population interactions
Food webs and connectance.
Compartments in food webs.
Food web topology.
Niche theory
Guilds and guild structure.
Spp composition, community assembly
A question of equilibrium.
Stability.
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The Structure of Community Ecology
Morin (1999)
Community Ecology
Putman (1993)
Community Ecology
Commonalities
Ecological communities - definitions
and a search for pattern.
CommunityPopulation
patterns
interactions
Food
webs
and connectance.
Space and time
Compartments in food webs.
Competition
Food web topology.
Niche theory
Predation
Guilds and guild structure.
Spp composition, community assembly
Food webs
A question of equilibrium.
Stability.
Niches
I: Communities,
Patterns and Processes:
Competition I, Competition II
Predation I, Predation II
Food Webs
Mutualisms
Indirect Effects
II: Factors Influencing Interactions:
Temporal Patterns
Habitat Selection
Spatial Dynamics
III: Large Scale Phenomena:
Causes and Consequences of Diversity
Succession
Applied Community Ecology
Logical difficulties with this organization
Community patterns
Space and time
Competition
Predation
Food webs
Niches
Pattern
Consideration
Process
Process
Concept/thing
Concept
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The Structure of Population Genetics
Hedrick (2000)
Genetics of Populations
Hartl & Clark (2007)
Principles of Pop. Genetics
General Background
The Diversity of Genetic Variation
Measures of Genetic Variation
Selection: An Introduction
Selection: Advanced Topics
Inbreeding
Genetic Drift
Mutation
Neutral Theory, Coalescence
Gene Flow, Population Structure
Linkage Disequilibrium, Recombination
Molecular Genetics and Evolution
Genetic & Phenotypic Variation
Organization of Genetic Variation
Random Genetic Drift
Mutation & the Neutral Theory
Darwinian Selection
Inbreeding, Pop. Subdivision, Migration
Molecular Population Genetics
Evolutionary Quantitative Genetics
Population Genomics
Human Population Genetics
The Structure of Population Genetics
Hedrick (2000)
Genetics of Populations
Hartl & Clark (2007)
Principles of Pop. Genetics
Gene Flow, Population Structure
Linkage Disequilibrium, Recombination
Molecular Genetics and Evolution
Human Population Genetics
Commonalities
General Background
& Phenotypic Variation
MeasurementGenetic
of diversity
The Diversity of Genetic Variation
Organization of Genetic Variation
Measures of Genetic Variation Mutation
Random Genetic Drift
Selection: An Introduction
Mutation & the Neutral Theory
Selection: Advanced Topics
Drift
Darwinian Selection
Inbreeding
Inbreeding, Pop. Subdivision, Migration
Genetic Drift
Migration
Molecular Population Genetics
Mutation
Evolutionary Quantitative Genetics
Neutral Theory, Coalescence Selection
Population Genomics
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Logical consistency of this organization
Diversity measures
Mutation
Drift
Migration
Selection
Pattern
Process
Process
Process
Process
Why the difference?
The architects of the modern synthesis
were not distracted by data!
(Vieulle and Slatkin 2002 )
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Ecology is a discipline “whose material
study is part of everyday encounters:
birds, bees, trees, and rivers”.
“It is, however, a mistake to imagine
that this familiarity makes ecology and
easy pursuit…the very familiarity of
ecological objects presents the
difficulties”.
(Allen & Hoekstra 1992, Toward a Unified Ecology)
A Different Structure for Community Ecology
Primary patterns
Processes
• Drift
• Speciation
• Dispersal
• Selection
(across space & time)
• Species diversity
• Species composition
Abiotic env.
Biotic interactions
• Competition
• Predation
• Etc.
(identity, traits, abundances)
Emergent patterns
• Productivity
• Stability
• Food web connectance
• Whatever you can think of
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Relating the many to the few
Ecological idea/model/theory
Processes
Island biogeography
Dispersal and drift
Resource competition
Selection (frequency dependent)
Metacommunity theory
Dispersal, selection, and drift
Neutral theory
Speciation and drift
Assembly rules
Dispersal and selection
Spatial/temporal heterogeneity
Selection (variable in space/time)
Food webs
Selection (frequency dependent)
Species pool theory
Speciation
Productivity/stress/disturbance
Selection (and speciation)
The Evolutionary
Modern Synthesis
(Stebbins 1971, modified by Kutschera
& Niklas 1994)
Dispersal
A (not so) Modern
Synthesis for
Community
Ecology? Speciation
Drift
Dispersal
(Selection)
Selection
& Drift
Selection
Selection
(Ricklefs & Schluter 1993)
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Global community
Speciation
Drift
Selection
Regional community
Dispersal
Dispersal
Speciation
Drift
Selection
Dispersal
Dispersal
Local
Community
(Speciation)
Drift
Selection
Note: Extinction results from drift & selection
Teaching Community Ecology
Processes
• Drift
• Speciation
• Dispersal
• Selection
Primary patterns
(across space & time)
• Species diversity
• Species composition
(identity, traits, abundances)
Advantages (I hope):
• Logical coherence
Emergent patterns
• Allow links among sub-fields
to be seen more clearly
• Productivity
• Stability
• Food web connectance
• Whatever you can think of
• Facilitate communication of
the conceptual core of the
discipline more clearly
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