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A marine biologist is studying a population of sea turtles that primarily feed on jellyfish. Over the last decade, there has been a significant decline in the jellyfish population due to ocean acidification impacting their reproductive cycle. What is the most likely long-term consequence for the sea turtle population?

  1. AThe sea turtles will develop new physiological adaptations to digest plastic pollution, mistaking it for jellyfish.
  2. BA decline in the sea turtle population due to a lack of primary food source, potentially leading to local extinction.
  3. CAn increase in the sea turtle population due to reduced competition for other food sources.
  4. DA shift in the sea turtles' diet to include a wider variety of prey, leading to increased biodiversity.
Show answer & explanation

Correct answer: B. A decline in the sea turtle population due to a lack of primary food source, potentially leading to local extinction.

If a keystone food source like jellyfish declines significantly, a specialized predator like the sea turtle, which relies heavily on it, will face severe food scarcity. This will lead to a decline in the sea turtle population, as they struggle to find enough sustenance.

Why the other options are wrong

  • A. Developing rapid physiological adaptations to digest plastic is highly improbable and unscientific; evolution takes much longer.
  • C. Reduced competition for other food sources is irrelevant if their primary food source is gone and they cannot easily switch.
  • D. While some diet shifts are possible, a dramatic and rapid decline in a primary food source often leads to population decline before significant dietary adaptation occurs.

Ecological Niche & Food Web Impact

An ecological niche describes the role and position a species has in its environment, including how it meets its needs for food and shelter. Disruption of a key food source profoundly impacts species with specialized diets.

  • Specialized feeders are vulnerable to changes in their primary food source.
  • Food webs illustrate feeding relationships; removal of one component affects others.
  • Population dynamics are directly linked to resource availability.

Memory trick: No jellyfish, no turtles, ecosystem in crisis!

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