Download Interactions in Ecosystems

Interactions in Ecosystems
Bio.2.1.2, Bio.2.1.3
Organisms and Their Environment
• Biotic: living
• Abiotic: nonliving
• Habitat: place where an organism spends its entire life
• can change or disappear; human interaction/natural changes
• Niche: an organism’s role and position in its environment
• Summary of its way of life and how it fits into its given ecosystem
Competition
• Intraspecific: within the same species
• Density dependent
• Can shape population
• Interspecific: among different species
• Competitive Exclusion Principle: competition for resources prevents
any two species from sharing the same niche
Predation
• Herbivores and carnivores
• Coevolution – predator and prey adaptations change in sync
• Bat and moth change frequencies
• Adaptations to evade predations
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Camouflage
Warning coloration
Mimicry
Startle mimicry
Living Relationships: Symbiosis
• Symbiosis: when organisms live together and interact regularly with
one another
• 3 Types: Mutualism, Parasitism, and Commensalism
Living Relationships: Symbiosis
• 1. Mutualism: both species involved benefit
• Ex. Ants and acacia trees, Egyptian plovers and crocodiles
Living Relationships: Symbiosis
• 2. Parasitism: one species benefits, the other is harmed
• Ex. Tapeworms, ticks, guinea worms, organism that causes malaria
Living Relationships: Symbiosis
• 3. Commensalism: one species benefits, the other is unaffected
• *some debate about this: some scientists believe commensalism is early
mutualism; relationship not completely understood yet
• Ex. Barnacles and whales
Living Relationships: Symbiosis
Symbiotic Relationship
Effect on Species
Mutualism
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Parasitism
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Commensalism
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