Ch. 50 ECOLOGY

1
Ch. 50 ECOLOGY

• Organisms are open systems that interact
  continuously with their environments
• Ecology gt 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
• Distribution
• Abundance
• Where/ how do they live/ why are they there ?
  Factors that influence these

2
Scope of Ecology

• Aristotle, Darwin, Ernst Mayr, EO Wilson, Aldo
  Leopold and Rachel Carson
• Historically descriptive, currently much more
  quantitative
• Data is important .much information is modeled
  due to extremely large scale.
• Abiotic gt nonliving, chemical and physical
  factors such as temperature, light, minerals,
  wind, latitude and longitude
• Biotic gt 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.

3
Relationship to evolution

• An important cause of evolution is an organisms
  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

4
Levels of Ecology

• Organismal Ecology morphology, physiology and
  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

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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

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Factors Affecting Distribution

• Global and regional
• Pangea (supercontinent)
• Biogeography study of past and present
  distribution
• Dispersal
• Think diffusion
• potential range vs actual range
• Dispersal behavior biotic factors abiotic
  factors.
• Transplants -
• Introduced species
• Invasive vs. exotic
• 10s rule

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Types of Dispersion

• Random Clumped Even
• individuals are individuals are
  individuals are
• not in any type grouped together spaced
  evenly
• of pattern through ecosystem

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Factors that impact dispersion

• Behavior / habitat selection
• Egg laying, host plant, prey, chemical signals,
• Biotic factors
• Predation, disease, competition, resources
• Abiotic factors
• Temperature, water, sunlight, wind, rock and soil
  ( pH, structure, minerals) , salinity
• Temperature and water are major - climate

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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
• Will potential cause changes in distribution of
  species . Spread disease, alter crop production,
  change in weather patterns.