Population Dynamics and Ecosystems PDF
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Uploaded by IrresistibleLorentz
Fulton Middle School
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Summary
This document explains population growth and decline, predator-prey relationships, and energy flow within an ecosystem. Topics include stable populations and the Ripple effect. Key concepts from biology are covered.
Full Transcript
Population Growth/Decline: Increase: Populations grow when more individuals are born than die (e.g., sharks, panthers). Decrease: Populations shrink when more individuals die than are born (e.g., deer, rats, sparrows). Predator-Prey Relationships: Predator Increase: Whe...
Population Growth/Decline: Increase: Populations grow when more individuals are born than die (e.g., sharks, panthers). Decrease: Populations shrink when more individuals die than are born (e.g., deer, rats, sparrows). Predator-Prey Relationships: Predator Increase: When predator populations (e.g., hawks, wolves) increase, they eat more prey (e.g., sparrows, deer), causing prey populations to decrease. Prey Decrease: A decrease in prey (e.g., grasshoppers, snails) leads to less food for predators, causing predator populations (e.g., rats, perch) to decrease. Energy Flow: More Food for Prey: If a food source for prey (e.g., snails, flies) increases, prey populations (e.g., perch, spiders) may increase due to more available energy for reproduction. Less Food for Prey: A reduction in prey’s food supply (e.g., smaller grasshopper or snail populations) causes predator populations to decrease because less energy is available. Stability & Effects: Stable Populations: Populations remain stable when birth and death rates balance, such as in stable squirrel or shark populations. Ripple Effects: A sudden change in one population (e.g., a decrease in aphids or grasshoppers) can impact other linked populations in the ecosystem (e.g., ants, rats, or perch).
