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Relationships between organisms . A love, hate thing…. Every organism has its place…. Every organism in an ecosystem has a role or job to carry out… That job and how it uses the conditions around it is called a niche Examples include:
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Relationships between organisms A love, hate thing…
Every organism has its place… • Every organism in an ecosystem has a role or job to carry out… • That job and how it uses the conditions around it is called a niche • Examples include: • an organism’s place in the food web; producer, consumer, decomposer. • How it interacts with other living things (biotic factors) • Where and how it lives out its life • Resources (abiotic factors) that affect it.
Many relationships exist among organisms: How do organisms interact? • Competition • Predation: predator and prey • Symbiosis • Mutualism • Commensalism • Parasitism
Competition • Competition exists between members of the same species and between species. • What are organisms competing for? • Resources: food, water, living space, etc.
Predator and prey Contrary to common thought… An organism won’t eat all the prey. What would happen to the predator
Symbiosis…..together at last! Sym; together Biosis: living Symbiosis is defined as a “relationship when two organisms live closely (in or on) together. Three types
Mutualism I’ll scratch your back if you scratch mine…
Commensalism When one member in the relationship is benefited and the other…well no harm, nor help
Parasitism One member is helped by the relationship and the other is harmed.
Succession Orderly, natural changes and species replacements that take place in the communities of an ecosystem. Often follows a predictable, orderly pattern. Two types: Primary and Secondary
Primary Succession: Starting with no soils… http://botit.botany.wisc.edu/images/veg/ Step 1 - Bare rock (0-1 years) Lichens grow on the bare rock (a pioneer species). As they die, the decaying lichens form soil so moss can grow.
http://botit.botany.wisc.edu/images/veg/ Step 2 - Grassland (2-4 years) Grasses and other small plants grow; out-competing the mosses for sunlight.
Step 3 - Transitional or shrub (5-20 years) Small shrubs such as dogwood and sumac begin to dominate.
Step 4 - Coniferous Forest (20-100 years) Pines and fir trees begin to shade out the smaller shrubs http://botit.botany.wisc.edu/images/veg/
Step 5 - Deciduous Forest (100-200 years) Large, slow-growing trees such as oak, maple and hickory replace the pines…if the abiotic factors “allow” it to happen.
Secondary Succession: Succession that occurs after a community is disrupted by natural disasters or human activity. Examples = fire, flood… *Occurs in a shorter amount of time because soil and sometimes seeds present.
Climax Community = a stable, mature community that undergoes little or no change in species. • Southern WI = Prairie • Baraboo = deciduous forests • Northern Wa= temperate rainforest in Olympics http://botit.botany.wisc.edu/images/veg/