1. Ch. 50 ECOLOGY “Organisms are open systems that interact 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 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 => 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.

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”

5. 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

6. 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 10’s rule

7. Types of Dispersion Random Clumped Even individuals are individuals are individuals are not in any type grouped together spaced evenly of pattern through ecosystem

8. 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

9. 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….