Question

Discuss the kinds of evolutionary interactions that occur between species.

Answer 1

Species interactions

• Species interactions include - 1. Mutualism

                                                         2. Commensalism

                                                         3. Ammensalism

                                                         4. Competition

                                                         5. Predation

                                                         6. Parasitism

1. Mutualism:

• In this type of interaction both the species are benefited.
• These interactions takes place in 3 patterns.
• The purposes of these 3 patterns  are defensive mutualism, trophic mutualism, and dispersive mutualism.
• The 3 patterns are Facultative mutualism - This is a pattern where the species can live on their own under favourable conditions.
• Obligate mutualism - This is pattern where one species is dependent for survival on the other.
• Diffusive mutualism: This is pattern where one entity can live with multiple partners.

2. Commensalism:

• In this type of interaction one entity benefits while the other is neither harmed nor benefited.
• This is of 4 types - inquilinism, chemical commensalism, phoresy,metabiosis.
• Inquilinism - This is an entity which occupies living habitat of another species. Ex: burrow, nest.
• Chemical commensalism: This is a type where a bacteria produces a chemical which nurtures the another bacteria.
• Phoresy: This is a type where an organism tentatively attaches itself to another entity for transportation requirements.
• Metabiosis: This is a type where one entity is dependent on the other for survival.

3. Ammensalism:

• This is a type of interaction where, when one population finds itself in danger the other population is not majorly affected.
• Example: Tall and wide plants hinder comparatively the growth of the smaller plants.
• Some plants even secrete substances which repress the growth of nearby plants in order to remove competition.

4. Competition:

• This is referred to as when the populations or even an individual compete for food resources.
• It is also known as exploitative or consumptive competition.
• Interference competition is when there is a competition for territory.
• Preemptive competition is when they compete for a new territory and have arrived first.

5. Predation:

• This is an interaction where one entity hunts another animal to suffice its nutritional requirements.
• A predator is an entity that hunts its prey.

6. Parasitism:

• This is an interaction where one entity benefits from other entities and is harmed, but is not necessarily killed.
• The entity which is harmed is the host and the one which is benefited is the parasite.
• Parasitoidism is referred as the type of behaviour when the host is killed.
• The ectoparasites are those which live on the surface of the host where as the endoparasites live inside the host.
• Endoparasites are of 2 types.
• They are -  intracellular parasites (which live inside the cells) and intercellular parasites (which live in spaces between the cells).

Ecosystem

Definition: 

• The ecosystem is defined as the system formed by the interaction of all living organisms with each other and with physical and chemical factors of the environment in which they live, all linked by transfer of energy and material.
• Example: Rain forest, Grassland, Dessert, Lake, Pond, etc.,