Mutualists and Phoronts of the Southern Pine BeetleThis article is part of a larger document. View the larger document here.
The large numbers of invertebrates and microbes that exist only within dying and decayed pines killed by the southern pine beetle (SPB) make this system ideal for the study of species interactions, including mutualism and phorecy. The associated organisms comprise an entire functioning community that includes fungivores, herbivores, detritovores, scavengers, parasitoids, and predators. Because the SPB causes physical state changes in biotic materials and creates a stable supply of resources for an extensive assemblage of species, it can be considered a keystone species, ecosystem engineer, or foundation species. Within the SPB community, species interactions range from mutualistic to commensalistic to antagonistic, depending on the species composition, environmental conditions, and quality of available resources. These species often use SPB adults to access and disperse among trees and can affect the population dynamics, behavior, and evolution of the SPB. In addition, interactions among the community can impact bark beetle-fungal associations and thus, beetle fitness. In this chapter, I provide an overview of the known associations with the SPB, both mutualistic and phoretic, and discuss how these associations impact the SPB and the evolution and ecology within this community.