Topic 1.1 Video Notes - Ecosystems
Ecosystems
Resource Availability and Species Interactions
Objective: Explain how resource availability influences species interactions.
Topics:
Predator and prey relationships.
Symbiosis: Close associations between different species.
Competition and resource partitioning (resource sharing).
Skill: Describing an environmental concept.
Ecosystem Basics
Individual: A single living organism (e.g., one elk).
Population: A group of organisms of the same species (e.g., an elk herd).
Community: All living organisms in a given area (e.g., trees, grass, beaver, rabbit, bacteria, fungi).
Ecosystem: Living organisms interacting with non-living components (rocks, soil, water).
Biome: A large area with a similar climate, determining the plants and animals that can live there (e.g., tropical rainforest).
Species/Organism Interactions
Competition: A lose-lose situation where organisms fight over a shared resource (food, shelter), limiting population sizes.
Predation: One organism uses another as an energy source (positive for predator, negative for prey).
Mutualism: A win-win relationship beneficial for both species (e.g., coral reef).
Commensalism: One species benefits, and the other is unaffected (e.g., birds nesting in trees).
Predation
Herbivory: Animals eating plants (technically predation because the plant is used for energy).
True Predators: Carnivores that eat other animals (e.g., leopards, lions).
Parasite: Uses another organism (host) for energy, usually without killing it (e.g., sea lamprey, mosquitoes, tapeworms).
Parasitoid: Lays eggs inside a host; the larvae eat their way out, often killing the host (e.g., parasitic wasp).
Symbiosis
Definition: A long-term interaction between two organisms of different species living in close association.
Types:
Mutualistic: Both species benefit.
Commensalist: One species benefits, and the other is unaffected.
Parasitic: One species benefits at the expense of the other.
Mutualism
A symbiotic relationship where both species benefit, often depending on each other for survival.
Example:
Coral Reef: Coral provide reef structure and carbon dioxide for algae; algae provide sugars (energy) via photosynthesis for coral. Coral are tiny animals called polyps. The algae lives inside the coral.
Lichen: A composite organism of fungi and algae; algae provide sugars, and fungi provide nutrients. They function as a single organism.
Competition and Resource Partitioning
Competition: A lose-lose situation where both species have smaller populations due to limited resources.
Resource Partitioning (Resource Sharing): Allows different species to utilize the same resource in slightly different ways to reduce competition.
Evolution favors traits that allow species to utilize the same resource differently, not a conscious strategy.
Types of Resource Partitioning
Temporal Partitioning: Species use the same resource at different times (e.g., wolf and coyote hunting at different times of day).
Spatial Partitioning: Species use different areas of a shared resource (e.g., grasses with different root depths; warblers occupying different parts of a tree).
Morphological Partitioning: Species evolve different body features to utilize different portions of the same resource (e.g., birds with different beak depths eat different seed sizes).
Resource Partitioning Benefit
Reduces competition, enabling species to thrive and grow to larger population sizes.
Food web Task
Identify two organisms that compete for a shared food resource.
Describe how resource partitioning could reduce the competition between these organisms.
Resource Availability and Species Interactions
Objective: Explain how resource availability influences species interactions.
Topics:
Predator and prey relationships.
Example: Lions (predator) hunting zebras (prey).
Symbiosis: Close associations between different species.
Example: Clownfish and sea anemones.
Competition and resource partitioning (resource sharing).
Example: Different bird species eating different insects in the same tree.
Skill: Describing an environmental concept.
Ecosystem Basics
Individual: A single living organism (e.g., one elk).
Population: A group of organisms of the same species (e.g., an elk herd).
Community: All living organisms in a given area (e.g., trees, grass, beaver, rabbit, bacteria, fungi).
Ecosystem: Living organisms interacting with non-living components (rocks, soil, water).
Biome: A large area with a similar climate, determining the plants and animals that can live there (e.g., tropical rainforest).
Habitat: The natural home or environment of an animal, plant, or other organism (e.g., a forest for deer).
Niche: The role and position a species has in its environment; how it meets its needs for food and shelter, how it survives, and how it reproduces (e.g., a beaver's niche includes building dams, which modifies its environment).
Species/Organism Interactions
Competition: A lose-lose situation where organisms fight over a shared resource (food, shelter), limiting population sizes.
Example: Lions and hyenas competing for the same prey.
Predation: One organism uses another as an energy source (positive for predator, negative for prey).
Example: Wolves hunting elk.
Mutualism: A win-win relationship beneficial for both species (e.g., coral reef).
Example: Bees pollinating flowers.
Commensalism: One species benefits, and the other is unaffected (e.g., birds nesting in trees).
Example: Barnacles attaching to whales.
Parasitism: One species benefits, and the other is harmed (e.g., ticks on a dog).
Example: Tapeworms living in a host's intestine.
Predation
Herbivory: Animals eating plants (technically predation because the plant is used for energy).
Example: Cows eating grass.
True Predators: Carnivores that eat other animals (e.g., leopards, lions).
Example: Sharks eating fish.
Parasite: Uses another organism (host) for energy, usually without killing it (e.g., sea lamprey, mosquitoes, tapeworms).
Example: A tick feeding on a deer.
Parasitoid: Lays eggs inside a host; the larvae eat their way out, often killing the host (e.g., parasitic wasp).
Example: Braconid wasps laying eggs in caterpillars.
Symbiosis
Definition: A long-term interaction between two organisms of different species living in close association.
Types:
Mutualistic: Both species benefit.
Example: Nitrogen-fixing bacteria in the roots of legumes.
Commensalist: One species benefits, and the other is unaffected.
Example: Cattle egrets following grazing cattle and eating insects stirred up by their movement.
Parasitic: One species benefits at the expense of the other.
Example: Fleas on a dog.
Mutualism
A symbiotic relationship where both species benefit, often depending on each other for survival.
Example:
Coral Reef: Coral provide reef structure and carbon dioxide for algae; algae provide sugars (energy) via photosynthesis for coral. Coral are tiny animals called polyps. The algae lives inside the coral.
Lichen: A composite organism of fungi and algae; algae provide sugars, and fungi provide nutrients. They function as a single organism.
Competition and Resource Partitioning
Competition: A lose-lose situation where both species have smaller populations due to limited resources.
Example: Two species of plants competing for sunlight in a forest.
Resource Partitioning (Resource Sharing): Allows different species to utilize the same resource in slightly different ways to reduce competition.
Evolution favors traits that allow species to utilize the same resource differently, not a conscious strategy.
Types of Resource Partitioning
Temporal Partitioning: Species use the same resource at different times (e.g., wolf and coyote hunting at different times of day).
Example: Owls hunting at night and hawks hunting during the day.
Spatial Partitioning: Species use different areas of a shared resource (e.g., grasses with different root depths; warblers occupying different parts of a tree).
Example: Different fish species feeding at different depths in a lake.
Morphological Partitioning: Species evolve different body features to utilize different portions of the same