The relationship between species richness (S, the number of species In fact, E essentially relies on the relative abundance distribution (RAD). species), relative abundance and diversity using computer-generated simulations. Species richness by an interrelationship among species richness, overall. Here we examine the relationship between species richness(S) and Species evenness or the similarity in species relative abundance in a.
On the other hand, theoretical analyses suggested that S—E relationships were correlated DeBenedictis, ; Gosselin, DeBenedictis stated that S was strongly positive with E. Hill hypothesized that S and E were related.
Jost and Tuomisto also suggested that E was actually constrained by S. Thus, E was affected by S in many theoretical cases.
If this is so, does species diversity consist of S and E? Is there a general understanding that can reconcile the conflict between theory and observation?
How do species richness and relative abundance of species affect species diversity?
In fact, E essentially relies on the relative abundance distribution RAD Gosselin,which is a description of the proportional abundance for each species in a community May, ; Tokeshi, ; McGill et al. Krebs stated that E was basically determined by RAD. The dependence of E on S is observed to be strong for most RADs, although they were rarely assessed by the raw data Gosselin, Altogether, this paper continued the study of evenness indices variation with species richness Gosselin,but with a specific RAD Su, Since there is only one parameter in this model, the empirical S—E relationship for each community can be indicated on S—E plots, which is the originality of this paper.
The hypothesis of this paper is that the S—E relationship relies on the pattern of RAD, which thereby determines the controversial issue that the diversity is or is not a compound quantity made up of S and E. Tropical rainforests are the richest habitat of all, tropical grasslands exhibit more diversity than temperate grasslands, and deserts in tropical or subtropical regions are populated by a wider range of species than are temperate deserts.
Another factor affecting the species richness of a given area is the distance or barrier that separates the area from potential sources of species.
How do species richness and relative abundance of species affect species diversity? | Socratic
The probability that species will reach remote oceanic islands or isolated valleys is slight. Animal species, especially those that do not fly, are less likely than plant species to do so.Abundance and Diversity
The Lesser Sunda Islands are similar to eastern Java in climate and vegetation, but they have far fewer strictly terrestrial animals. This situation is attributed to the fact that, whereas Java has been connected to a larger landmass in the past, the Lesser Sundas have not.
While plants and seeds have been blown across intervening seas, few species of animals that do not have wings have reached these islands. Species adaptations to ecological habitats Neither an environment nor an organism is a static entity. Hence, changes in either will disrupt the relationship that has evolved between the two. Changes of an extreme nature, however, are almost always maladaptive. Small environmental variations may present a challenge that organisms can meet by mounting a physiological response or, if they are mobile, by removing themselves to a less stressful area.
Catastrophic disruptions, however, may create an environment no longer hospitable to the organisms, and they may die out as a result. Although the distribution patterns of species are dictated by environmental conditions, the actual range of a species is not identical to its potential range—namely, the area that is ecologically compatible with its needs. For example, the biogeographic regions of the world are related to climatic factors, but they are not coterminous with them.
The effects of geologic changes on biotic distributions The theory of plate tectonicsformulated in the s, is now firmly established. Its explanation of the dynamic nature of continental landmasses has been important not only within the field of geology but also within the field of biogeography; it has entirely revolutionized the interpretion of the dispersal of flora and fauna see also plate tectonics: Plate tectonics as an explanation for Earth processes. The slow movement of continents has been used to explain both the isolation and intermingling of populations.
Prior to the acceptance of this idea, land bridges and sunken continents were invoked as the means by which continents were linked in the geologic past. While land bridges, such as the Bering Strait land bridge that connected western North America to Asia, have existed and contributed to the dispersal of organisms, they no longer are believed to have been as ubiquitous and instrumental in this process as once was thought.
Such hypothetical land bridges as Archhelenis, which purportedly connected South America and southwestern Africa, are now regarded by most experts as relics of the fertile imaginations of early biogeographers.