Chapter 9 - A Metapopulation Approach to Interpreting Diversity at Deep-Sea Hydrothermal Vents

Abstract

This chapter provides an introduction to the natural history of vent ecosystems in the deep sea, and gives an example of how metapopulation models can be used to address one class of questions about species diversity patterns at vents. Hydrothermal vent communities inhabit the deep sea in locations where volcanic activity causes hot, chemical-rich fluids to exit the seafloor. The majority of invertebrates inhabiting deep-sea vents can live only in vent habitats. More than 440 species have been observed at vents, most of which are endemic species. Hydrothermal vent communities are apt examples of metacommunities: a group of interacting species inhabiting a set of habitat patches that are connected via dispersal and subject to local extinction. Two simple metacommunity models are analyzed to try to determine whether the hypotheses that have been advanced to describe the few patterns documented are consonant with mathematical reasoning. This analysis also raises the possibility that species interactions, particularly obligate facilitative interactions, become important when habitat is sparse and difficult to colonize. These interactions may result in diversity patterns that cannot be predicted using only considerations of vent dynamics or species colonization abilities.