Examples of commensalism

What is commensalism?

Commensalism is the word derived from the English word commensal which means eating at the same table or sharing food generally using of one's waste food as another food or sharing food without any harm to other  .

Commensalism is a type of relationship between two plants, animals, mammals or fungus, etc. where one lives with another without damaging the other.

Commensalism may be defined as the practice or situation in nature where two species live close together in association where only one partner gets the benefit and the other is neither helped nor harmed and remain as usual. One of the species gain from increased food supply mainly  but the other gets nothing from the relationship.

For example:

·        Silverfish and Army Ants: Silverfish cleans the nest of army ants without harming them.

·        Human and Roaches: Roaches eat the garbage, humans leave behind.  

·        Remoras and Sharks: Remoras eat the scraps which are scattered by the sharks feeding.

A bird that is living in a tree can be an example of commensalism..  Here the bird live in the tree to get shelter, where the tree does nothing and is neither helped nor harmed by the bird.

The species that benefits from the relationship can obtain shelter, support or locomotion from the host species which greatly remain unchanged. The relation is often between larger host and a smaller commensal.

Some organisms connect themselves to some other organisms for transportation or to achieve better access to food. Others use the host as a shelter. Such as: Squirrel and trees acts vice versa. A tree usually grows the fruits and nuts and squirrel just eats them.

Examples of Commensalism

Cattle, horses and other livestock, usually graze in the field. They cause movement in which various insects stir up. Cattle egrets following the livestock catch and feed upon them. The egrets benefit from this relationship as because the livestock helped them find their meals. The livestock remains unaffected.

     

The cattle egret is a general species of heron. They are found in almost every region of the world. They are mostly seen moving along with the shepherd of cattle. The bird moves around and follows the cattle. The cattle egret eats the insects those are hiding themselves under vegetation near to the ground and get moved up when the cattle walks through them. Here the cattle get the benefit by eating the insects and the livestock remains unaffected totally.

Orchids, a flowering plant grows on the branches of trunks or other trees. Orchids are generally found in tropical forests. They form their bases on the branch of trees and gains benefit by getting sunlight and nutrition that flows down the branches. The orchids do not grow large and hence the host tree is not harmed any way. 

Some species of pseudo-scorpions hide themselves under the wing covers of large insects like beetles protect them from the predators and provide a way of transportation. Pseudo-scorpions are scorpion like insects, very small in size almost one centimeter in length or even less than that. As it has no sting, does not harm the beetle in any way.

A common wild plant called burdock is found along a roadside or generally in an empty field. You can see the seed heads in the picture have long spines with hooked tips. The hooked tips, catches the hair of cows, dogs, deer or human passing by and are carried elsewhere until they are pulled off by the carriers.