1. Which statement best defines an invasive species?
- A. A species that migrates to a new ecosystem seasonally.
- B. Any species that lives in an ecosystem it was not originally from.
- C. A native species that has become overpopulated due to a lack of predators.
- D. A non-native species whose introduction causes harm to the ecosystem.
2. If an invasive predator that eats small birds is introduced to an island, what is the most immediate and direct effect on the native parrot population?
- A. The parrot population will likely decrease due to increased predation.
- B. The parrots' main food source will suddenly become more abundant.
- C. The parrots will quickly evolve new defenses against the predator.
- D. Other native predators on the island will help the parrots fight the new predator.
3. A fast-growing invasive plant is introduced to a forest. It quickly covers the ground and grows over small native shrubs. What is a likely primary impact of this plant?
- A. It will provide a valuable new food source for all native herbivores.
- B. It will block sunlight, preventing native plants from growing.
- C. It will make the soil more fertile for native tree seedlings.
- D. It will attract more pollinating insects to the forest.
4. In an ecosystem where native parrots help pollinate a specific type of flower, what is a potential indirect effect if an invasive predator significantly reduces the parrot population?
- A. The flower population may decline due to a lack of pollination.
- B. The invasive predator will start pollinating the flowers instead.
- C. The flowers will quickly adapt to be pollinated by insects.
- D. The soil nutrients will increase, causing the flowers to grow larger.
5. Why does the introduction of a single invasive species, like feral cats, often disrupt the stability of an entire ecosystem?
- A. It causes the climate of the ecosystem to change rapidly.
- B. It increases the overall biodiversity by adding a new species.
- C. It alters the food web and outcompetes native species for resources.
- D. It forces native species to migrate to a completely new environment.
6. In an ecological food web, what fundamentally determines an organism's role as a producer or a consumer?
- A. Its method of obtaining energy
- B. Its physical size and weight
- C. Its typical lifespan
- D. The time of day it is most active
7. A food web model is used to study the declining Orange-Bellied Parrot population. If these parrots are primary consumers that eat seeds, which change in the ecosystem would most directly explain their decline?
- A. An increase in the population of the plants whose seeds they eat
- B. A decrease in the population of hawks that prey on the parrots
- C. A widespread fungal disease that destroys their primary seed-producing plants
- D. An increase in the activity of decomposers like bacteria and fungi in the soil
8. Which statement best describes the flow of energy as it is represented in a typical food web model?
- A. Energy flows from top predators down to the producers.
- B. Energy is created by consumers and transferred to producers.
- C. Energy flows in one direction from producers to consumers.
- D. Energy cycles continuously between producers and decomposers.
9. Scientists add a newly discovered invasive snake to the food web model. The snake preys on the eggs of the Orange-Bellied Parrot. How should this new relationship be illustrated in the model diagram?
- A. An arrow pointing from the snake to the parrot.
- B. An arrow pointing away from both the parrot and the snake.
- C. An arrow pointing from the parrot to the snake.
- D. A dotted line connecting all producers to the snake.
10. What is a key advantage of using a simplified food web model to study a complex ecosystem?
- A. The model can perfectly predict the exact future population of every species.
- B. The model is a tool that allows scientists to form and test hypotheses about how changing one part of the system might affect other parts.
- C. The model accounts for every single environmental variable, including daily temperature and rainfall, making it a perfect replica of nature.
- D. The model eliminates the need for any direct field observation of the animals.