COEXISTENCE

Species Coexistence

Species Coexistence

Introduction

Species coexistence can be understood by taking a better look as an individual species' way of life (ecological niche), but its importance is a highly contentious topic as heightened variability makes it difficult to differentiate species. Niche difference signifies that species respond differently to their surrounding (Arditi. 2005). There are loads of situations and examples that depicts such phenomenon (Grinnel, 1917), that prove that species interact and respond differently is different environment settings. Species are able to coexist regardless of minor differences as when these differences are enough to reduce inter-specific competition (a situation in which species different species fight over the same resource) below intra-specific competition (a situation in which the same species fights for the same resources) (Bascompte et al, 2007). Figure 1.1 and Figure 1.2 in the Appendix depict the results of various experiments.

If two species were considered niche, distinguished qualities would be required to differentiate them. In actuality, there are various issues related to this approach because accurately measuring quality and traits of species would require a proper observation of multiple sources. Many examples can provide conclusive evidence to accurately differentiate between species' traits if the statistical sample is large enough. Classical theories predict that two similar species cannot coexist with one other due to competition over the resources. During the past few years, these theories have been challenged by various models in which stochasticity plays an imperative role in the development of the community structure of “non-differentiated” species. Various statistical methods have been used to conclude such theories; these tools include distributions and curves that prove that similar species can live together. Although, some experts have argued that stochasticity sometimes blurs the understanding coexistence of species as they mask complex, multi-dimensional behavior. In many areas, ecologists ignore the impact of stochasticity because it is very difficult to apply. Since there are several conflicting views, experiments are necessary to produce conclusive evidence.

Discussion

In order to test the coexistence experiment, three different species were selected. Of these 3, only P. B was supposed to engage in symbiosis. Symbiosis is a situation in which 2 different organisms live together in close association. There are 3 different types of symbiosis (Grabianowski, 2001):

Mutualism: Mutualism is when both organisms benefit from the relationship.

Parasitism: Parasitism is when one organism benefits and one is hurt by the relationship

Commensalism: Commensalism is a relationship in which one organism benefits and the other is not affected. Orchids can illustrate this.

Experiment of Coexistence between the Virginia Warbler and the Orange Crowned Warbler

There have been several experiments conducted by various ecologists who have tested the coexistence of species in different environments. One of these experiments was conducted by Martin et al. (2001, pp.189-206) on the coexistence of Virginia Warblers with Orange Crowned Warblers in various conditions and environments. The following were the results of their experiments in various different conditions.

In the first experiment, the limiting resources were nest sites. In most cases, both the orange crowned warblers and the Virginia warblers built their nests on shrubs placed ...