Certain species of ibex and weevils depend on the same food source. A study finds that the removal of ibex results in an increase in the number of weevils, but the removal of weevils does not affect the ibex. Which one of the following options best describes this interaction?
Show Hint
- Amensalism
- Commensalism
- Mutualism
- Parasitism
The Correct Option is A
Solution and Explanation
Amensalism is a biological interaction where one species is harmed while the other remains unaffected. In this scenario, the removal of ibex leads to an increase in weevil numbers, suggesting that the ibex negatively affects the weevils. However, the removal of weevils does not impact the ibex population, indicating the ibex is unaffected by the weevils.
Step 2: Analyze the other options.
- Commensalism: One species benefits and the other is unaffected — not applicable here as ibex do not benefit from the weevils.
- Mutualism: Both species benefit — clearly not the case here.
- Parasitism: One species benefits at the expense of another — again, ibex do not benefit from weevils.
Top Questions on Ecology
- Which one or more of the following would make a plant community more susceptible to invasion by exotic plants?
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Figure F shows how predation rate changes with increasing prey density.
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Questions Asked in GATE EY exam
- An organization allows its employees to work independently on consultancy projects but charges an overhead on the consulting fee.
The overhead is 20% of the consulting fee if the fee is up to ₹5,00,000.
For higher fees, the overhead is ₹1,00,000 plus 10% of the amount by which the fee exceeds ₹5,00,000.
The government charges a Goods and Services Tax (GST) of 18% on the total amount (i.e., the consulting fee plus the overhead).
An employee of the organization charges this entire amount — that is, the consulting fee, overhead, and tax — to the client.
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After the 1st round, the 4th student behind P leaves the game.
After the 2nd round, the 5th student behind Q leaves the game.
After the 3rd round, the 3rd student behind V leaves the game.
After the 4th round, the 4th student behind U leaves the game.
Who all are left in the game after the 4th round?
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Note: All lengths are in meter. The figure shown is representative.
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P: Over time, such adaptations lead to significant evolutionary changes with the potential to shape the development of new species.
Q: In natural world, organisms constantly adapt to their environments in response to challenges and opportunities.
R: This process of adaptation is driven by the principle of natural selection, where favorable traits increase an organism’s chances of survival and reproduction.
S: As environments change, organisms that can adapt their behavior, structure, and physiology to such changes are more likely to survive.