Transcript Ch. 50 ECOLOGY

Ch. 50
ECOLOGY
 “Organisms are open systems that interact
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continuously with their environments”
Ecology => the scientific study of the interactions
between organisms and their living and nonliving
environments.
Resources are limited
Multidisciplinary field with lots of practical importance
Questions include
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Distribution
Abundance
Where/ how do they live/ why are they there ? Factors
that influence these
Scope of Ecology
 Aristotle, Darwin, Ernst Mayr, EO Wilson, Aldo Leopold and
Rachel Carson
 Historically descriptive, currently much more
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quantitative
Data is important ….much information is modeled
due to extremely large scale.
Abiotic => nonliving, chemical and physical factors
such as temperature, light, minerals, wind, latitude
and longitude
Biotic => living components of the environment, such
as food, resources, water, competition, prey, specific
species
Many times biotic and abiotic factors overlap =
neighboring trees are competition and also provide
shade.
Relationship to evolution
 An important cause of evolution is an organisms
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interactions with its environment.
Lots of geologists at the same time as Darwin
Ecological timeframes may be in months or years.
Eventually translates to evolutionary changes
Evolutionary changes are on a different time scale
(geologic time = millennia and eras)
Ex: predator-prey interactions provide the force for
genetic selection of a camouflaging color
Web – like , wide variety of interactions
Levels of Ecology
 Organismal Ecology: morphology, physiology and
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behaviors of a species as they meet challenges of
interacting with their environment
Population Ecology: What factors affect a certain
group (species) as they live in a particular area
Community Ecology : interacting species
Ecosystem Ecology : species plus all the abiotic
factors in the ecosystem
Landscape Ecology: how are ecosystems arranged in
a particular geographic region.
Ecosystem = community plus physical environment
Biosphere = region of Earth where life is found,
“global ecosystem”
Levels of organization
 Individual
 Species = similar individuals that are
genetically similar enough to reproduce and
produce viable offspring.
 Population
 Community
 Ecosystem
 Biomes = regions on the globe that are
similar in climate and vegetation
 Biosphere
Factors Affecting Distribution
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Global and regional
Pangea (supercontinent)
Biogeography : study of past and present distribution
Dispersal
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Think diffusion
potential range vs actual range
 Dispersal – behavior – biotic factors – abiotic
factors….
 Transplants  Introduced species
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Invasive vs. exotic
10’s rule
Types of Dispersion
 Random
individuals are
not in any type
of pattern
Clumped
Even
individuals are
individuals are
grouped together spaced evenly
through ecosystem
Factors that impact dispersion
 Behavior / habitat selection
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Egg laying, host plant, prey, chemical signals,
 Biotic factors
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Predation, disease, competition, resources
 Abiotic factors
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Temperature, water, sunlight, wind, rock and
soil ( pH, structure, minerals) , salinity
Temperature and water are major - climate
Variations in climate
 Seasons
 Microclines – from top to bottom of lake or
forest, from edge to interior of forest
 Climate change – long term shifts in the
climate of a specific biome. ( glaciers )
 “climate change” is more accepted (pc) than
“global warming”
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Will potential cause changes in distribution of
species …. Spread disease, alter crop
production, change in weather patterns….