Chapter 4, Problem 1TYC

To determine

To explain: The way in which competition leads to realized niche and also the way in which it promotes resource partitioning.

Answer to Problem 1TYC

Competition, both interspecific and intraspecific types, can control and limit the ecological role served by an individual, leaving it to fill just a part of its full potential role, which is referred as the fundamental niche. This more restricted role is denoted as realized niche. Competition instills adaptations in the species so that they evolve themselves to use different resources, or to use shared resources in different ways. This is known as resource partitioning.

Explanation of Solution

Competition is type of species interaction in which individuals from two or more species compete with each other for resources like food. However, competing organisms do not directly fight among themselves physically, rather it will be more indirect and delicate as the organisms compete each other to obtain resources.

Competition could become a negative interaction, if at least one of the species shows signs of the negative effect, which may include unhealthy individuals, reduced number of individuals or even death of organisms among a specific species population.

Though the nature has an abundance of resources, the resources that a particular species can use are limited. Thus, when multiple species need the same resources, competition arises. To minimize competition, nature has developed two ways: realized niche and resource partitioning.

A species can wander in a large area (fundamental niche) for resources, however, due to the competition from other species, it gets restricted to a smaller section of its fundamental niche, the area which would be then referred as realized niche. As organisms from other species would have their own realized niches, the species face lesser competition.

Resource partitioning occurs since the species divide or partition the resources they use in common by adopting different specialization. Resource partitioning would give rise to character displacement, where competing species becomes different in terms of their physical features due to the evolution of characters best suitable to the choice of resources they make.

Realized niches, segregate the area where organisms find resources but in resource partitioning, mechanisms are developed in which two species coexist in the same region and find resources in the same region without interfering with each other. One example of this is the Anolis lizards of Puerto Rico.

It has two species inhabiting the same forests. The two species are: Anolis evermanni and Anolis gundlachi. A. evermanni searches for its food in the branches two meters above the ground. On the other hand, A. gundlachi finds food in the area that is just two meters from the ground.