introduction to ecology part 1 – designed & edited by joe naumann 1

Introduction to EcologyIntroduction to Ecology

Part 1 – Designed & Edited by Joe Naumann

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The Science of EcologyThe Science of Ecology

Differentiate Between Ecology and Environmentalism and Conservation Biology

Trace History of Ecological Thought Define Ecology Scientifically Learn the Scientific Method Organization of Ecology

Goals for the day

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Goals for the day

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Ecology vs Ecology vs EnvironmentalismEnvironmentalism

Scientific societies and activist groups – often in conflict with each other

Earth First, Greenpeace, and WWF

Industry – e.g., GMO’s: Pandora’s box or chicken little?

Individuals vs populations◦ Hawaii: PETA vs Nature

Conservancy

or

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Hawaii: PETA vs Nature Hawaii: PETA vs Nature ConservancyConservancy

Feral pigs (Sus scrofa)◦Integral part of native

Hawaiian Luau culture ◦Introduced by both

Polynesians and Europeans (2 spp)

◦Rooting destroys many plants

◦Create wallows, water collects, and encourages mosquitoes to breed

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Hawaii: PETA vs Nature Hawaii: PETA vs Nature ConservancyConservancyNature Conservancy◦Attempting to

eradicate the pig from their lands

◦Uses ecological impact of pigs as justification for their removal

◦Capture through noose snare-trapping, as this is the easiest way to capture the animals

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Hawaii: PETA vs Nature Hawaii: PETA vs Nature ConservancyConservancyPETA

◦Recognizes the impact that these pigs have on the ecology

◦Snare-trapping is protracted, inhumane, and a painful way to kill them

◦Advocates for humane trapping and then quick kills

◦Ignores financial cost 7

Hawaii: PETA vs Nature Hawaii: PETA vs Nature ConservancyConservancyResolution?

◦ Still to be found◦ Nature Conservancy

continues to trapA few write-ups of

the controversy are available from the Honolulu Advertiser

A more general discussion of invasives in Hawaii is availble from USGS

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Key DistinctionsKey DistinctionsEcology is a science

◦Our focus in this course

Environmentalism is a cause◦With our without scientific backing

Conservation Biology is the integration of these two◦Using science to support a political

cause

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Goals for the day

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History of Ecological History of Ecological ThoughtThoughtFrom Thoreau to

modern timesHistorically has been

literature-based appreciation of nature

Subsequently became more of a descriptive science

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Darwinian ReferencesDarwinian References“…how infinitely

complex and close-fitting are the mutual relations of all organic beings to each other and to their physical conditions of life.”◦Origin of Species

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Trace History of Ecological Thought

Define Ecology Scientifically Learn the Scientific Method Organization of Ecology

Goals

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Definition of EcologyDefinition of Ecology

“To determine the factors that have produced the present distribution and abundance of organisms”

◦ (Jonathan Krebs, 1972)

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Factors Influencing Factors Influencing Organismal Distribution and Organismal Distribution and AbundanceAbundance

Abiotic◦Climate◦Topography◦Latitude◦Altitude

Biotic◦Intraspecific

Interactions◦Interspecific

Interactions15





Goals

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Scientific Method and Hypothesis Scientific Method and Hypothesis TestingTestingGoals:

◦Judge good science Hudson River PCB

dredging Electromagnetic

radiation and cancer Sea otters, killer

whales and overfishing

◦Do good science

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Goals of scienceGoals of scienceDescribe the patterns that are found

in the natural world◦Purely descriptive in nature◦Historically this was “ecology”, a.k.a.

naturalism Make up explanations and then stop there

Test Explanation of Patterns◦This is the major emphasis of most of

what we usually call “science”◦Key component: TEST these

explanations!How to test these explanations?

◦The Scientific Method 18

Methods of ExplanationMethods of ExplanationInclude those of descriptive scienceApproximately 11 StepsProcess is repeated many timesCan NEVER prove a hypothesis

◦Can only reject many, leaving one as best supported by the data

◦“Proof” is a common fallacyCenterpiece of this method are Hypotheses

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Types of HypothesesTypes of Hypotheses

Null hypothesis◦The hypothesis of no change◦Often abbreviated as Ho

Alternative hypotheses ◦Often abbreviated as Ha, Hb, etc.

◦All must be mutually exclusive (including the null)

◦We accept an Ha if Ho is first statistically rejected Which Ha to accept is determined by

trends in data 20

Scientific Method - Steps Scientific Method - Steps 1-51-51. Observe or suspect pattern 2. Posit cause or significance of

observed difference 3. Create answerable question

to explain pattern 4. Create testable hypotheses

◦ Null (Ho ) and alternate hypotheses (Ha)

5. Design experiment 21

Scientific Method - Steps 6-Scientific Method - Steps 6-1111

6. Collect data (descriptive stage) 7. Analyze data, primarily using

statistics 8. Evaluate hypotheses, reject Ho?

9. Make conclusions based on data

10.Note problems in current work11.Predict future directions for

research22

An Exercise…An Exercise…Recall an observation that you’ve

seen recently and think through how you would implement the above 11 steps

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Parts of a scientific reportParts of a scientific report

Title Abstract - an overall summary Introduction - background, question,

HasMethods - what we didResults - what we found, analyses

results Discussion - interpretations,

predictions Acknowledgements - who helped us References - who we cited 24

Transmission Methods in Transmission Methods in ScienceScience

Written report (articles, chapters, books)◦Traditional

Oral presentation ◦Commonly used for preliminary presentation of work to get feedback before writing it up

Poster ◦Visual summary of work - used at conferences

Web page ◦Can use a written report & make it interactive

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How to Evaluate Science?How to Evaluate Science?Do the data address the question?Is there enough data to support the

claim?Has the study been replicated

elsewhere?Are alternative interpretations

considered?Is it peer-reviewed?Is it presented objectively?Are there real controls?

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Goals

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What is the Organization of What is the Organization of Ecology?Ecology?Ranges widely from individual to

biosphere studiesMost of ecology happens in the current time◦Proximate Explanations

Only a few fields (e.g., evolutionary ecology and paleoecology) are concerned with past environments and historical time◦Ultimate Explanations

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Proximate FieldsProximate FieldsEmphasis of this courseExamples, by scale

◦Population Growth rates, PVA, Population genetics,

Metapopulation analyses, etc.

◦Community Interspecific interactions, Environmental

impact statements, etc.

◦Ecosystem Energy, Matter, Nutrient flow, Pollution,

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Ultimate FieldsUltimate FieldsEvolutionary Ecology

◦Using trees of relationship (phylogenies) to address ecological questions

◦E.g., evolution of swordtail length and preference in platys

Behavioral Ecology◦Comparing a few closely related species to

address ecological questionsPaleoecology

◦Attempting to recreate the ecology of ancient times

◦One of the goals is to recreate the ancient environment in which the lineages may have evolved

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Proximate Fields RevisitedProximate Fields RevisitedTrends down pyramid:

◦Increase in geographic scale

◦From single species to multiple species

◦Increasing number of ecological factors that may be influential

◦Decreasing certainty in results

Population

Community

Ecosystem

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introduction to ecology part 1 – designed & edited by joe naumann 1

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