Commensalism: One Species Benefits — NEET Biology
✅ Asked in NEET 2024Commensalism: This is the interaction in which one species benefits and the other is neither harmed nor benefited. An orchid growing as an epiphyte on a mango branch, and barnacles growing on the back of a whale benefit while neither the mango tree nor the whale derives any apparent benefit. The cattle egret and grazing cattle in close association, a sight you are most likely to catch if you live in farmed rural areas, is a classic example of commensalism. The egrets always forage close to where the cattle are grazing because the cattle, as they move, stir up and flush out insects from the vegetation that otherwise might be difficult for the egrets to find and catch. Another example of commensalism is the interaction between sea anemone that has stinging tentacles and the clown fish that lives among them. The fish gets protection from predators which stay away from the stinging tentacles. The anemone does not appear to derive any benefit by hosting the clown fish.
Commensalism is a symbiotic relationship where one species benefits while the other is neither harmed nor benefited. NTA specifically tests the cattle egret example: egrets forage near grazing cattle to catch insects stirred up by them, while cattle gain nothing. Students often confuse commensalism with mutualism (both benefit) or parasitism (one harmed). The key distinction: the cattle egret benefits, but cattle experience no harm or benefit—it's not mutual gain. Remember: commensal = one-sided benefit with no cost to the host organism. This concept appears repeatedly because it tests understanding of symbiotic relationship categories, critical for ecology sections.
This paragraph was tested 2 times in NEET.
Assertion (A): The interaction in which one species benefits and the other is neither harmed nor benefitted is known as commensalism. Reason (R): Egrets always forage close to where the cattle are grazing, otherwise, it is difficult for the egrets to find the insects and catch them.
Which of the following is not an example of mutualism?
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