Commensalism Examples

Commensalism is a scientific term. It refers to a relationship between two living things from different species in which one of the organisms benefits. While the other organism does not benefit from the relationship, it is also not harmed by it.

Often, commensalism occurs between a larger species and a smaller one. The smaller organism is usually the beneficiary of the relationship and it is called a commensal. A commensal relationship can benefit the smaller species in many ways, including gaining nutrients, shelter, or support from the larger species.

The remora rides attached to sharks and other types of fish. The remora benefits by gaining a measure of protection, and it feeds off of the remains of the meals of the larger fish.

The cattle egret is a type of heron that will follow livestock herds. The cattle egret benefits because it eats insects that are stirred up when the livestock move through the grass.

The monarch butterfly stores a poisonous chemical from the milkweed plant in its body. This chemical makes other animals who might eat the monarch butterfly sick. So, the butterfly uses the milkweed for protection.

Barnacles are a type of crustacean that attach to whales. Barnacles cannot move on their own, so they use the whale to move around and find locations with food.