Conserving Interaction Biodiversity

Summary

Priorities for conservation of biodiversity have been based primarily on concerns over species and ecosystems: maintenance of species diversity and ecosystem functions, and retention of genetic variation within populations. But the links between species and ecosystems occur through the interspecific interactions that shape the organization of biological communities. We now know, as a result of research in evolutionary ecology over recent decades, that interspecific interactions can sometimes evolve quickly under changed environmental conditions. For example, restriction in gene flow among populations can lead to divergence among populations in the outcomes of interactions; increasing host density and increasing transmission rates of infectious parasites (as can occur in isolated reserves) has the potential to favor the evolution of higher levels of parasite virulence; and the loss of metapopulation, or broader geographic, structure in interactions may disrupt the revolutionary process that maintains traits such as some resistance genes in plant populations. Hence, the continuing evolution of interactions as we change their spatial dynamics has important immediate effects on conservation efforts and priorities. Concerns over the evolution and conservation of “interaction biodiversity” cannot be something simply added on to the long list of other concerns in conservation biology. They must be an integral part of efforts to maintain evolutionarily viable conserved communities. To do so requires concerted research efforts to better understand the geographic scale at which interactions evolve among species, and the retention of some large unmodified landscapes in which such studies can be carried out.