which of the following is an example of commensalism?
Which of the following is an example of commensalism?
Answer: Commensalism is a type of symbiotic relationship where one organism benefits from the interaction while the other is neither helped nor harmed. This balanced and neutral association differs from other symbiotic relationships like mutualism, where both organisms benefit, and parasitism, where one organism benefits at the expense of the other.
1. Bird Nesting in Trees
A classic example of commensalism involves birds that build their nests in trees. In this relationship, the bird benefits by having a safe place to raise its young and protect them from predators. Meanwhile, the tree remains unaffected by the bird’s presence. The tree isn’t harmed by the nest or the bird, nor does it gain any advantage from providing this habitat.
2. Remora Fish and Sharks
Another illustrative example is the relationship between remora fish and sharks. Remoras have specialized sucker-like fins that allow them to attach to sharks and other large marine animals. By hitching a ride, remoras benefit by gaining free transportation through the water and access to food scraps from the shark’s meals. The shark, on the other hand, is unaffected by the presence of the remora. It neither gains any benefit from carrying these passengers nor suffers any detriment.
3. Orchids Growing on Trees
Orchids often grow on the branches of trees in tropical forests. The orchid benefits by being elevated and gaining better access to sunlight, which is necessary for its photosynthesis and growth. The tree, meanwhile, remains unaffected by the presence of the orchid. The plant doesn’t extract water or nutrients from the tree, hence it doesn’t harm the tree by competing for resources.
4. Barnacles on Whales
Barnacles often attach themselves to the skin of whales. The barnacle benefits by getting transported to plankton-rich waters, which provides it with better feeding opportunities. Similar to the remoras and sharks, the whale is not affected by the presence of the barnacles. The whale continues its journey unaffected by these small hitchhikers, showing a clear case of commensalism.
5. Egret and Cattle
Egrets often follow cattle in the fields, feeding on insects stirred up by the movement of the cattle. The egret benefits by having an easier time catching its prey, while the cattle remain unaffected by the presence of the birds. The cattle do not receive any benefit or harm from this association, demonstrating yet another example of commensalism.
Summary
Commensalism reflects a fascinating ecological interaction where one species derives some benefit while the other remains unaffected. It underscores the complexity of ecological relationships and how different organisms coexist within ecosystems. Notably, the examples provided—birds nesting in trees, remoras on sharks, orchids on trees, barnacles on whales, and egrets with cattle—highlight the varied forms this relationship can take in the natural world. These examples aid in illustrating the subtle yet intriguing intricacies of commensal interactions.