Population Interaction

Population Interaction in the Ecosystem

The study of different organisms, their scattered presence over different regions, and their interaction or communication with each other and the surrounding environment comes under the umbrella of Ecology.  The theory of population interaction is extremely crucial to be understood fundamentally prior to the understanding of the concepts and relationships between predators and prey, camouflage, competition, mimicry, hunting strategies, etc.

Definition of Population Interaction

According to the population interaction definition, the interaction among populations is the interaction between different species of organisms in the ecosystem. It takes into account the effects that organisms belonging to a community have on everybody else and one another. 

There are two kinds of factors, the abiotic one or the physical factor and the biological one or biotic factor in the environment. Some physical factors like nutrients of the soil, water, carbon dioxide, atmospheric pressure, wind, etc. are important for and needed by a living organism to live. The different kinds of populations and their interactions can be affected a lot by these abiotic factors, which are a part of the ecosystem. Mentioned below are the major modes of interaction between different populations or the types of population interaction:


It is an interaction between two or more than two species of organisms when they compete. The competition is for limited resources, which all the competitors want control of, at the same time. These resources can be area, food, water, or any other prey. As these things are important for sustaining, these resources are mainly the ones for which competition happens.


In a predation relationship, there is a full dependency of one kind of species over the other species for their survival and food. The one that gets preyed for food is called the prey. The species which feeds on the other kind of species is termed as a predator species.

Several instances of the food chains, food webs, etc. are based on this concept, where a predator keeps on relying on other species for food during its entire life cycle. In some cases, the predator can also become prey to some other species. All the living organisms have their own defense and attack strategies, which they use to become safe from the stronger species or to hunt down the weaker species.

This relationship is witnessed not just within the animal kingdom but also plant kingdom. Predator and prey can also be applied to animal and plant relationships. For example, a goat feeding on grass or a panda eating bamboo.


It is an effective defense survival strategy used by various organisms to develop structural adaptation and physical characteristics similar to their surroundings and blend with it in order to be safe and not get found by the predators actively looking for them. Many animals like chameleons, lizards, frogs, leopards, etc. use this technique for their own advantages for hiding away from predators.


In the Greek language, symbiosis means to live together. There are situations in which many species of organisms depend on each other for survival. They depend on each other for food in most cases. One organism lives with another exhibiting a mutual stereotypical behaviour in this case. There are different types of population interactions of Symbiosis kind.

Types of Symbiosis Interaction

1) Mutualism 

It is a biological relationship or interaction between two or more species of organisms. In this type of population interaction, each species is profited in some or the other way from the other species. This is the most common type of ecological interaction. It explains that mutual dependency is needed and is necessary for the social well-being of different species. It is prominent in most populations of organisms around the globe.

[Image will be Uploaded Soon]

2) Commensalism 

It is a unique kind of relationship where two or more species of organisms depend on each other for food or survival and get benefitted, but without harming each other or anyone.

[Image will be Uploaded Soon]

3) Parasitism 

Parasitism involves one organism feeding off another organism. It is a case of one-sided symbiosis. The organism that feeds off another species is called a parasite, and the prey species is called the host. The parasites multiply, causing harm to the hosts.

[Image will be Uploaded Soon]

FAQ (Frequently Asked Questions)

Question 1: What are the Different Examples of Mutualism, Commensalism, and Parasitism Interaction?

Answer: There are several population interactions examples which can be witnessed on day to day basis, they are: 

  • Oxpecker and zebra 

Oxpecker is a kind of bird that eats flies, insects, etc. from the zebra and other grazing animals. The animals get rid of insects in this way, and the birds get their food. This is an example of mutualism population interaction.

  • Tree frog and trees 

The frog hides under the leaves to protect itself from rain, storm, or predators. This is an example of commensalism as no species is harmed while getting benefitted from one another. 

  • Mosquitoes and humans 

The mosquitoes are parasites here, and the humans are the hosts. Mosquitoes feed on human blood for survival, and humans, in turn, get harmed. This is an example of parasitism population interaction. 

Question 2: What are the Examples of Competition and Camouflage Population Interactions? 

Answer: Herbivores like gazelles are the prey for dangerous predator species like a group of lions and a group of hyenas. Both of these groups are carnivorous predators and can compete to get the prey to themselves in order to satiate their hunger and survive. This is an example of competition population interaction. 

Stonefish adapts itself to the rocks of the ocean and camouflages with them in order to not get seen by bigger predator fishes like sharks. It also does this while hunting smaller fish as they would not be able to differentiate between the stonefish and its surroundings and fall prey to it. This is an example of camouflage population interaction.