Question

Differentiate between. Commensalism and amensalism

Answer 1

Hint: Biological interactions are the interactions between organisms in an ecosystem. The organism can influence another organism positively or negatively. If interacting organisms are of the same species they are called intraspecific interactions. If two interacting organisms are of different species they are called interspecific interactions.

Complete answer:
Interactions can be broadly classified into the following types;
1.Mutualism
2.Commensalism
3.Parasitism
4.Neutralism
5.Amensalism
and Competition.

Mutualism – Interaction in which both interacting species are benefited is called mutualism. Commensalism – Biological interaction where one organism receives the benefit and another organism neither receives benefit nor gets harmed. Parasitism – Interactions where parasites feed on the host. The parasite receives benefit and the host is harmed. Neutralism – interactions where interacting species are not benefited. Amensalism – the type of interactions where one organism is affected but another organism does not receive the benefit. Competition – the type of interaction in which the fitness of one organism is lowered by another organism.
The difference between Commensalism and Amensalism is as below-

Commensalism	Amensalism
Commensalism is a positive interaction between organisms.	Amensalism is a negative type of interaction between the organism.
One organism receives the benefit.	The interacting organism does not receive the benefit.
Another organism involved in interactions remains unaffected.	Another organism involved in the interaction is harmed.
Examples; golden jackal following lions, epiphytic plants such as orchids, hermit crabs living inside a dead snail shell.	Examples; secretion of penicillin by penicillium which is toxic for bacteria, Black walnut secreting secondary metabolites from roots which is toxic for other plants.

Note: Biological interactions can be long term as well as short term. All the above-mentioned interactions are long term interactions. Pollination and Predation are examples of short term interactions.