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Community Interactions. Community Interactions. Community : Many different species interacting in the same environment. Three types of interactions: Competition Predation Symbiosis. Competition. Defined : competing for resources water, nutrients, light, food
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Community Interactions • Community: Many different species interacting in the same environment. • Three types of interactions: • Competition • Predation • Symbiosis
Competition • Defined: competing for resources • water, nutrients, light, food • occurs due to a limited number of resources • Intraspecific competition: When organisms of the same species compete for resources. • Interspecific competition: When organisms of differing species compete for resources. • Competitive exclusion principle: no two species can occupy the same niche in the same habitat at the same time
Predation • Defined: when an organism captures and feeds on another organism. • Predator- hunter • Prey- hunted
Symbiosis • Defined:any relationship where two species live closely together. • Three types • Mutualism • Commensalism • Parasitism
Mutualism Fungus obtains nutrients from the algae Fish receives protection and a home • Defined: both species benefit from a relationship. • Ex: Lichens (fungus and Algae) • Ex: Clown fish and anemones • Ex: Cleaner birds and crocodiles Algae lives amongst the fungal cells Anemone feeds on undigested food from the fish Bird receives food Crocodile has parasites removed
Commensalism • Defined: One member of a symbiotic relationship benefits and the other is neither helped nor harmed • Ex: Cattle and Birds • Birds eat insects stirred up by the cattle • Ex: Barnacles and whales • Barnacles grow on whale
Parasitism • Defined: One creature benefits and one creature is harmed • Endoparasitism: A parasite that inhabits the inside an organism. • Ex: Tapeworm feeds within a human’s intestines absorbing his/her nutrients • Ectoparasitism: A parasite that inhabits the outside of an organism. • Ex: A leech feeds on the blood of an organism from a host’s skin.
Review • What is a community? • Name the 3 types if community interactions. • When do organisms usually compete? • How do predators and prey interact? • Name the 3 types of symbiosis. • How is predation and parasitism differ? • How does mutualism, commensalism, and parasitism differ?