Symbiotic associations with bacteria are found virtually everywhere in nature. In order for host-microbe associations to evolve, the symbiosis must be stably re-established by each new generation of host. We are investigating the mechanisms involved in helping to maintain host-microbe specificity from the broad evolutionary scale down to the molecular level. To do so, we primarily study a highly specific, binary symbiosis between a coral reef fish (Siphamia tubifer) and a luminous bacterium (Photobacterium mandapamensis).

We have determined that unique aspects of the host’s life history and behavioral ecology, play important roles in promoting specificity of the bioluminescent association between host generations. We also characterized the degree of specificity of the association throughout the host’s broad Indo-Pacific distribution and across all 25 species in the host genus. Future work will focus on defining the genetic mechanisms that regulate symbiont recognition and the establishment of the association.