An Introduction to Biodiversity Theory

The science of biodiversity originates largely from ecology (the study of the relationship between organisms and their environment) and evolution (the study of the origin of diversity). From these two fields come its two main goals: to understand the way the natural systems work and are structured, and to understand how it got that way.

Why study biodiversity? Although the theory of biodiversity can be studied for its own sake to gain a better idea of how the world works, it has several important practical uses, mostly centred on conservation. By understanding the theory, we can better understand which types of species are most likely to decline under different circumstances and also know how best to protect those species from extinction. If diversity is reduced in an area, we can also best prevent further loss and try to restore the lost diversity if we have a good grasp of what the outcome of different actions, such as reintroducing lost species, will be. As human activities continue reduce the biodiversity on the planet, it becomes increasingly important to know what the effect of our actions will be before we lose any more diversity.

This section consists of four parts. The first introduces the three levels of biodiversity that are studied, the second looks at how diversity can be gained or lost, the third examines the composition of diversity in more depth, and the fourth looks at how biodiversity affects the functioning of ecosystems. Each of these only scrapes the surface of the research available; the References section of this site lists more detailed resources.

As one would expect, theory is a complex issue, full of new concepts and terms. This is the most difficult section of the site, and much of the complexity is unavoidable.

Page 2 The three levels of biodiversity

Page 3 Gaining and losing biodiversity

Page 4 Composition and abundance

Page 5 Biodiversity and ecosystem functioning