Eucalyptus: Example of Amensalism

What is - definition

Also known as antibiosis, amensalism is an interspecific ecological relationship (between different species) and disharmonic (one species is favored from the relation to another). In amensalism, one species (animal or plant) harms another with the purpose of obtaining benefits for itself in relation to environmental resources.

This relationship is very common in environments where environmental resources are scarce (space, water, light, food, etc.). Thus in amensalism there is a kind of competition.

Examples of amensalism:

- Some fungal species (penicillium notatum, for example) release substances (eg antibiotics) to harm certain species of bacteria, thereby preventing their proliferation and thus obtaining more resources (destined for the development of fungi) from the environment.

- Roots of some plant species make it difficult for other plants to germinate. Thus, the former benefit from obtaining the resources necessary for their development, avoiding competition.

- There are plants (eucalyptus, for example) that exude substances around them, whose purpose is to block the germination of other plant species that are “competing” in the same space.

- In the phenomenon known as “red tide” that occurs in marine waters, a species of algae (dinoflagellates) releases toxins into the water to harm other marine species living in that environment. This way, they get more resources for their development.