Ecological restoration aims to recreate lost or degraded ecological communities. However, “community” has been a difficult concept to define – should the definition stress dominant species, species interactions, or a subset of strongly interacting species? These authors propose defining community on the basis of co-evolutionary relationships among species.
We propose that an Evolutionary Community is conceptualized as a unique grouping of species, which occur in a given geographic area and are connected by interspecific and abiotic interactions that have evolved over time [Steen 2017: 1021].
By treating communities “as entities that have formed over evolutionary time; this [Evolutionary Community] concept allows for a philosophical platform to help us understand what many conservation and restoration efforts are trying to accomplish” [Steen 2017: 1031]. That is, it offers a way to conceptualize the end goal of a restoration project. A particular evolutionary community could be recreated by assembling the constituent species, resulting in the ecological interactions among the species resuming as before.
What processes cause a group of species to cohere into a community? We argue that the parts of Evolutionary Communities are bound together by interspecific interactions in a shared biotic and abiotic environment, which promote co-evolution and community structure and dynamics. For example, longleaf pine trees are conduits for lightning strikes that ignite a highly flammable understory, often including dropped longleaf pine needles. The resulting ground fires are necessary for reproduction of other species and maintain habitat suitable for others (e.g., gopher tortoises). Gopher tortoises, through the process of burrow creation, provide structure important to other species. The establishment of one or more of the species listed above facilitated the persistence of additional species [Steen 2017: 1025].
Likewise, the demise of one species will negatively affect, or even cause the demise of, other species that depend on it. Thus, the reason to preserve or recreate an integral community is to support the interdependent component species, each of which in turn support the community as a whole.
Steen, David A., Kyle Barrett, Ellen Clarke, & Craig Guyer, 2017, Conceptualizing communities as natural entities: a philosophical argument with basic and applied implication, Biol. Philos. 32, https://link.springer.com/article/10.1007/s10539-017-9589-8