Functional ecology

The notion that ecosystems' functions can be affected by their constituent parts has its origins in the 19th century. Charles Darwin's On The Origin of Species is one of the first texts to directly comment on the effect of biodiversity on ecosystem health by noting a positive correlation between plant density and ecosystem productivity. By the 1950s, Elton's model of ecosystems was widely accepted, where organisms that shared similarities in resource use occupied the same 'guild' within an ecosystem. Beginning in the 1970s, an increased interest in functional classification revolutionized functional ecology. 'Guilds' would be re-termed 'functional groups', and classification schemes began to focus more on interactions between species and trophic levels. Functional ecology became widely understood to be the study of ecological processes that concern the adaptations of organism within the ecosystem. In the 1990s, biodiversity became better understood as the diversity of species' ecological functions within an ecosystem, rather than simply a great number of different species present. Finally, in the 2000s researchers began using functional classification schemes to examine ecosystems' and organisms' responses to drastic change and disturbance, and the impact of function loss on the health of an ecosystem. == Functional Diversity ==

Functional diversity is widely considered to be "the value and the range of those species and organismal traits that influence ecosystem functioning" Increased functional diversity increases both the capacity of the ecosystem to regulate the flux of energy and matter through the environment (Ecosystem Functions) as well as the ecosystem's ability to produce resources beneficial to humans such as air, water, and wood (Ecosystem Services). However, the statistical validity and setup of these experiments have been questioned, and require further investigation to carry substantial merit. However, by defining the functional trait probability density as a "function representing the distribution of probabilities of observing each possible trait value in a given ecological unit," the results of many models can be generalized to larger scales. At larger spatial scales, more environmental heterogeneity may increase opportunities for species to exploit more functional groups. Consistent with this conclusion, tests of theoretical models predict that the net effects of biodiversity on ecosystem functions grow stronger over time, over larger spatial scales, and with more heterogeneous natural resources. However, these results are expected to underestimate the actual relationshipm impling that large space and time scales coupled with diverse resources are more than necessary to sustain an ecosystem. == Applications of Functional Ecology ==

A functional approach to understanding and dealing with environments provides numerous benefits to our understanding of biology and its applications in our lives. While the concept of functional ecology is still in its infancy, it has been widely applied throughout biological studies to better understand organisms, environments, and their interactions. Species Detection and Classification The notions of functional ecology have beneficial implications for species detection and classification. When detecting species, ecologically important traits, such as plant height, influence the probability of detection during field surveys. When holistically analyzing an environment, the systematic error of imperfect species detection can lead to incorrect trait-environment evolutionary conclusions as well as poor estimates of functional trait diversity and environmental role. Under this paradigm, functional traits are defined as morpho-physiophenological traits which impact fitness indirectly via their effects on growth, reproduction and survival. in the levels above or below them. On the other hand, discovering the traits/functions that genes encode for yields insight into the roles that organisms perform in their environment. This kind of genomic study is referred to as genomic ecology or ecogenomics. To avoid reintroducing a species that is rendered functionally redundant by one of its ancestors, a functional analysis of global ecosystems can be performed to determine which ecosystems would benefit most from the added functional diversity of the reintroduced species. These considerations are important because, while many species currently being considered for de-extinction are terrestrial, they are also functionally redundant in their former ecosystems. However, many extinct marine species have been identified as functionally unique in their environments, even today, which makes a strong case for their reintroduction. In fact, while some functions have been recovered by evolution, as is the case with many extinct terrestrial species, some functional gaps have widened over time. Reintroducing extinct species has the potential to close these gaps, making richer, more balanced ecosystems. Furthermore, before a species goes extinct in the classical sense of the word, keeping a functional perspective in mind can avoid "functional extinction". Functional extinction is defined as "the point at which a species fails to perform its historical functional role". Endangered species such as species of tigers, tuna and sea otters usually qualify for this threshold. If functional ecology is considered, new species (not necessarily extinct) can be introduced into ecosystem where a species has become functionally extinct before any de-extinction action ever needs to be taken. This can be a key transformative process in ecological preservation and restoration because functional extinction can have cascading effects on the health of an ecosystem. For example, species that engineer ecosystems such as beavers are particularly unique functionally; their absence from an ecosystem could be devastating. While functional arguments for reintroduction of extinct species may paint thoughtful reintroduction as an ecological boon, the ethical and practical debate over de-extinction has not left functional approaches unscathed. The main critique of functional arguments in favor of de-extinction are largely focused on contentions that ecological functions are often ambiguously defined and that it is unclear what functions must be present to define an ecosystem. These arguments suggest that reintroducing an extinct species could be drastically harm an ecosystem if conclusions about its function or the functions of the species it is intended to replace are incorrect. Additionally, even if an extinct species' function is well understood de-extinction could be equally harmful if the function served by the extinct species is no longer needed by the ecosystem. == Journals ==

The scientific journal Functional Ecology is published by the British Ecological Society since 1986 == See also ==