Biology and other Life Sciences
The term symbiosis is derived from two terms, ‘sym’, which means with and ‘biosis’ meaning living. Perhaps, one can infer the meaning of a symbiotic relationship from the broken form of the term. However, scientifically, the concept of symbiosis involves the complex interaction between two organisms that both seek to benefit from the association. Often, the organisms interacting are drawn from different species for it to qualify under the definition of a symbiotic relationship. Further, symbiosis has three broad categories that are majorly anchored on the effect of the relationship. Commensalism, Mutualism, and parasitism have all been described against the expected benefit of the relationship between the different species that interact in this scientific phenomenon. This paper will explore the concept of symbiosis sighting various examples.
Mutualism can be looked at as a positive-positive scenario in which both organisms benefit positively from the interaction. The organisms are then said to benefit mutually from the biological relationship. Commensalism, on the other hand, involves a relationship that is founded on a positive-neutral basis. Contrary, in parasitism, only one of the organisms gets all the benefits from the relationship creating a scenario whereby one organism survives at the expense of another organism. Scholars have considered this to be a positive-negative relationship since one of the partners obtains negative benefits from the association.
Mutualism is based on a mutual benefits association in which both partners in the interaction seek individual gains. This case is highlighted by mycorrhizal fungi and plants. The relationship between the two is established when the fungi enter the roots of the plants. Fungi are essential for the survival of some plants. The fungi make hyphae, structures that resemble small branches. The hyphae act to increase the surface area for the absorption of water and other nutrients. Moreover, fungi enhance the decomposition of matter that promotes the survival of plants. In turn, the fungi acquire food in the form of starch from the plants thereby satisfying the symbiotic relationship. Importantly, the fungi obtain the starch directly from the plant cells without causing any disease in the plants.
Commensalism stems from the association between two different species in which one partner benefits positively while the other remains neutral regarding benefit or harm. A good example of such a relationship can be seen in the case of remoras and Manta rays. Manta rays, which are a species of huge fish, prey on crustaceans and other small fish. Occasionally, some of the food not eaten by the Manta Rays fish will be consumed by the remoras. The remoras have specialized suction discs that enable them to attach themselves strategically to the rays fish. Subsequently, when the Manta Rays fish eats, some of the leftovers that are left behind become exploited by the remoras. Since the life of the Manta Rays fish is unaltered while the remoras benefit from the association, this can correctly qualify as a commensalism kind of relationship.
Parasitism is considered when one organism in a relationship between different species benefits while the other partner gets harmed. Simply put, in this relationship, one of the organism exploits the other for its survival. Perhaps the perfect example of parasites are the mistletoe plants. All subspecies of these plants have been classified as parasites. They are well adapted as aerial parasites. For their survival, they must exploit the defense mechanism of plants in order to utilize their water and nutrients. Water remains the crucial resource that the mistletoe plants seek to survive. For a long time, critics have debated on the classification of this relationship as being parasitic and not mutualistic. Many people think that the mistletoe can be correctly considered as branches of the trees to which they are attached. However, scientific evidence shows that the mistletoe plants offer no assistance to the photosynthetic processes of the plants. Therefore, the only possible classification is that of parasitism. Another well-studied example of a parasitic relationship is that of plants and nematodes. Nematodes have earned numerous scientific classifications. In spite of this, the parasitic mechanism employed by these organisms have often been similar. All nematodes have are considered obligate and have a stylet. Simply put, nematodes are supposed to feed on plants at some point in their life cycle in order to finish their developmental cycle. The nematodes exploit water and nutrients from plants for both survival and development. Interestingly, the nematodes have been divided into two subcategories based on how they parasitize their hosts. Ectoparasites exploit their nutrients from the outsides while endoparasites obtain their nutrients from the inside.
In conclusion, symbiosis represents a diverse form of association between organisms that are drawn from different species. There exist three categories based on the kind of benefit obtained by the various partners in the symbiotic relationship. These relationships span the complex interaction of the various organisms in their bid to survive. Mutualism, commensalism, and parasitism are the three major forms of symbiosis covered in biology. However, some relationships clash in the boundary between parasitism and commensalism.