EcosystemsWhy might a change in an ecosystemaffect populations of species within that ecosystem?
Have you ever seen a caterpillar munching on a leaf, or a bird drinking water from a puddle? Have you noticed that the leaves of some trees only change color as the weather gets cooler?All of these observations, and others like them, areexamples of the many different types of interactionsthat occur within ecosystems.
An ecosystem includesall the living organismsexisting together in aparticular area. Theseorganisms, like plantsand animals, depend oneach other to survive.They also interact withthe nonliving elementsof the area, such aswater, soil, rocks, andclimate. Click here for more information about ecosystems.
Click here to Click here to playwatch a short a quick video vocabulary game Click here to read a short news article
The balance of an ecosystem is very delicate! Changes to the ecosystem, such as theintroduction of a new species or drought, can be disastrous to all organisms within the ecosystem.
Images courtesy of Jack and June Anthony of jjanthony.comThese three pictures show the growthof kudzu in an area over time. Predicthow the invasion of kudzu will affectother plants and animals in this area. Click here for more information about kudzu.
Click here for a Click here to play short video a quick game about other invasive species Click here to read a news article
Part 1: Print these instructions before clicking onthe link below. Use the virtual ecology lab tosimulate the disruption of an ecosystem by aninvasive plant species.Part 2: After completing part 1, start thesimulation over and try to create a sustainableecosystem in which all of your species survive. Ifone species has a population of zero at the end ofthe simulation, start over and try a differentscenario. Which scenario creates the most stableecosystem? Go to Virtual Ecology Lab
Virtual Ecology Lab Instructions Part A) Simulating a stable ecosystem:a) Click on All Off.b) Click on Plant C (the third plant in the row) and select it from the menu.c) Click on Herbivore A (the first herbivore in the row) and set it to eat Plant C.d) Click on Omnivore A (the first omnivore in the row) and set it to eat Herbivore A.e) Click RUN and observe that the plant, herbivore, and omnivore populations eventually reach equilibrium (their population numbers stop changing).Part B) Simulating the disruption of an ecosystem by an invasive plant species:a) Click on Reset. (Plant C, Herbivore A, and Omnivore A should still be connected in a food chain.)b) Click on Plant A (the first plant in the row) and select it from the menu. This plant represents an invasive species, a strong competitor to Plant C.c) Click RUN. What happens to the populations of each species in the ecosystem? Give an explanation for the results. (hint: think of a chain reaction or domino effect) PART A PART B
EcosystemA community of living and nonliving things that function together.Examples: – aquatic ecosystems – desert ecosystems – forest ecosystems
SpeciesA group of individual organisms that can interbreed and produce fertile offspring.Examples: – humans – cats – wolves
Invasive speciesNon-native organisms that are harmful to the ecosystem they invade.Examples: – Kudzu vine to the southeastern U.S. – Caribbean tree frog to Hawaii
DroughtA period of dry weather caused by a lack of rain.
1. Define – Ecosystem – Species2. Explain how the invasion of kudzu affects other plants and animals within the ecosystem.3. Why might a change in an ecosystem affect populations of species within that ecosystem?
Credits• The Habitable Planet – Ecology Lab• How Stuff Works• Kudzu Covered Houses• neoK12• NOVA beta – Invasive Species Matching Game• Geography 4 Kids• USDA National Invasive Species Information Center• Unless otherwise noted, all photos are from the internet and were labeled free to use, share, or modify, even commercially.
Kudzu, a vine native to Asia, was introduced to the United States in 1876. Eventually, it was used all over the South as a way to control soil erosion. Unfortunately, kudzu became a major problem. The climate of the southeastern United States is perfect for kudzu. With no natural predators in the area, it can grow up to a foot per day (~30 cm)! This invasive species grows over anything it touches, including trees, telephone poles, even houses!