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NEETZoologyOrganisms and Populations

In a classic field experiment conducted in the rocky intertidal communities of the American Pacific Coast, all individuals of the starfish Pisaster were removed from an enclosed area. What was the immediate ecological consequence of this removal, and what was the underlying reason?

Options

  1. AThe prey populations increased exponentially and reached the carrying capacity due to the absence of the preda
  2. BMore than 10 species of invertebrates became extinct within a year due to increased interspecific competition.
  3. CMore than 10 species of invertebrates became extinct within a year due to severe intraspecific competition.
  4. DThe invertebrate prey species faced starvation and extinction due to the sudden depletion of their food resour

Correct answer

B. More than 10 species of invertebrates became extinct within a year due to increased interspecific competition.

Step-by-step solution

In the rocky intertidal communities of the American Pacific Coast, the starfish Pisaster acts as an important predator. When all the starfish were experimentally removed from an enclosed intertidal area, it resulted in the extinction of more than 10 species of invertebrates within a year. This occurred because the predator (Pisaster) normally keeps prey populations under control. In its absence, the intensity of interspecific competition among the prey species increased significantly, leading to the competitive exc

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