Keep the Curiosity Alive
Look at this food chain: Sun → Grass → Grasshopper → Frog → Snake If frogs disappear from this ecosystem, what will happen to the population of grasshoppers and snakes? Why?
The food chain is: Grass → Grasshopper → Frog → Snake
Frogs are the predators of grasshoppers and the prey of snakes.
Effect on Grasshoppers (prey of frogs):
With no frogs to eat them, grasshoppers lose their main predator. Their population will increase rapidly because they continue to reproduce but face no check from predation. With more grasshoppers consuming grass, the grass population may also decline over time.
Effect on Snakes (predator of frogs):
Snakes depend on frogs as their primary food source in this chain. With frogs gone, snakes have nothing to eat at that trophic level. The snake population will decline and may eventually die out locally (or be forced to find alternative prey, if any exists in that ecosystem).
This illustrates how the removal of one organism creates a cascading effect — called a trophic cascade — that changes the population sizes at multiple levels of the food chain above and below it.
Answer: Grasshopper population will increase (no predator to control it). Snake population will decrease (loses its food source). The removal of frogs causes a trophic cascade affecting all other levels of the food chain.