Ecosystem Changes and Food Chains

The video explores how changes in an ecosystem, such as diseases or favorable growing conditions, can impact a food chain. Using a desert food chain in Australia as an example, it examines the effects of a disease on blue tongue lizards and a good growing season for grass. These changes affect the populations of bull ants, blue tongue lizards, and wedgetail eagles, demonstrating the interconnectedness of species within a food chain.

What is a common cause of significant changes in an ecosystem?

• Regular seasonal changes

• Disasters

• Animal migration

• Daily weather variations

In the described food chain, which organism is the producer?

• Wedgetail eagles

• Grass

• Blue tongue lizards

• Bull ants

What role do bull ants play in the food chain?

• Producers

• Primary consumers

• Secondary consumers

• Tertiary consumers

What happens to the wedgetail eagle population if the blue tongue lizard population decreases due to disease?

• It fluctuates unpredictably

• It decreases

• It remains the same

• It increases

How does the bull ant population change when blue tongue lizards are affected by disease?

• It becomes extinct

• It increases

• It remains stable

• It decreases

What is the effect on grass when there is an increase in bull ants due to fewer predators?

• Grass becomes more nutritious

• Grass population decreases

• Grass population remains stable

• Grass population increases

What leads to an increase in all species in the food chain during a good growing season?

• Increased predation

• Abundant rainfall

• Migration of new species

• Decrease in sunlight

How does an increase in grass affect the bull ant population?

• It decreases

• It remains the same

• It increases

• It becomes extinct

What is the overall effect on the food chain when grass has a good growing season?

• Only predators increase

• Only grass increases

• All species decrease

• All species increase

What should be considered when analyzing changes in food chains?

• The color of the species

• The effects on every other species

• The speed of the changes

• The geographical location