Ecology BIO 340
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Transcript of Ecology BIO 340
Ecology BIO 340
• What is Ecology– The scientific study of
the interactions that determine the distribution and abundance of organisms
Introduction
• What is not ecology?
Biological Disciplines Relating To Ecological Study
Biological Disciplines Relating To Ecological Study
EVOLUTIONEVOLUTION
BEHAVIOBEHAVIORR
GENETICSGENETICS
PHYSIOLOGYPHYSIOLOGY
Applied Ecology; Management
18th Century
Thomas Malthus Exponential Growth
19th Century
Natural History Human Demography
Ernst Haeckel• Defined “ecology”
• Coined phrase “ontogeny recapitulates phylogeny”
• Studied Foraminiferans
• Controversial ideas
20th Century
• Lotka & Volterra (1920’s)
Model population growth
• Gause (1920’s)
Manipulative Experiments
20th Century
Leopold (1930’s)
Natural ResourcesMacArthur (1960’s)
Mathematical Ecology
Geographical Ecology
20th Century
Lindeman (1942)
Trophic Dynamics
Hutchinson (1950’s)
Niche Concept
20th & 21st Century
Charles Krebs
Populations/Cycles
BIO 340 Student
?Monica Turner
Landscape
Ecology
Introduction
• Major Questions– Where are organisms
found?
– Where aren’t organisms found?
Introduction
• Major questions– How many are found
there?
Introduction
• Major questions– Why are organisms
found here and not there?
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Introduction
• Levels to ask questions– Individuals
• Behavior
• Physiology
Introduction
• Levels to ask questions– Populations
• Change in size
• Temporal & Spatial
Introduction
• Levels to ask questions– Communities
• Biotic interactions
Introduction
• Levels to ask questions– Ecosystems
• Community & Physical Environment
Introduction• Levels to ask
questions– Landscapes
• Spatial patterns
Introduction
• Levels to ask questions– Biosphere
Organization of Biological WorldBiosphere
Landscape
Ecosystem
Community
Population
Individual
Organ
Tissue
Cell
Organelle
Atom
INCREASED KNOWLEDGEINCREASED KNOWLEDGE
INCREASED COMPLEXITYINCREASED COMPLEXITY
Types of Ecological StudyTypes of Ecological Study
• AUTECOLOGY– Study of
individuals– Physiology
/Environment
Types of Ecological StudyTypes of Ecological Study
• SYNECOLOGY
– Study of groups of organisms
– Community level and above
Introduction
• How to look at a question– Proximate explanation
Introduction
• How to look at a question– Ultimate explanation
“Nothing in biology makes sense except in the light of evolution”Theodosius Dobzhansky
Introduction• Major Advances
– Mathematical Modelseppcdt
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Introduction
• Major Advances– Evolution
Introduction
• Major Advances– Hypothesis Testing
• Testing ideas about how the natural world works
• A hypothesis is developed to explain an observed phenomenon.
– Example: giraffes have long necks because the long necks enable them to reach food that is unavailable to others.
• Testing Ideas about How the Natural World Works– Null Hypothesis
• Hypothesis of no difference– Example: The length of a giraffe’s neck does not influence the height at which it forages.
– Alternative Hypothesis• Example: The length of a giraffe’s neck does influence the height at which it forages.
Most feeding is done below neck height.Males Females
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• Testing Ideas about How the Natural World Works– Null Hypothesis
• Hypothesis of no difference– Example: The length of a giraffe’s neck does not influence the height at which it forages. ACCEPT
– Alternative Hypothesis• Example: The length of a giraffe’s neck does influence the height at which it forages. REJECT
• Testing Ideas about How the Natural World Works– Null Hypothesis
• Hypothesis of no difference– Example: The length of a giraffe’s neck does not influence the height at which it forages. ACCEPT
– So why do they have such long necks?– Alternative hypotheses
• suggest a different explanation– Example: giraffes have long necks because long necks are effective weapons for one male against another during mating
(Simmons and Scheepers).
Hypothesis Testing and Experimentation
• Testing Ideas about How the Natural World Works– The predictions made by each hypothesis are
determined– Observations are made and/or an experiment is
designed to obtain data regarding the predictions