Publication Date:
2016-03-18
Description:
Insect microbe associations are diverse, widespread, and influential. Among the fitness effects of microbes on their hosts, defense against natural enemies is increasingly recognized as ubiquitous, particularly among those associations involving heritable, yet facultative, bacteria. Protective mutualisms generate complex ecological and coevolutionary dynamics that are only beginning to be elucidated. These depend in part on the degree to which symbiont-mediated protection exhibits specificity to one or more members of the natural enemy community. Recent findings in a well-studied defensive mutualism system (i.e., aphids, bacteria, parasitoid wasps) reveal repeated instances of evolution of susceptibility or resistance to defensive bacteria by parasitoids. This study searched for similar patterns in an emerging model system for defensive mutualisms: the interaction of Drosophila , bacteria in the genus Spiroplasma , and wasps that parasitize larval stages of Drosophila . Previous work indicated that three divergent species of parasitic wasps are strongly inhibited by the presence of Spiroplasma in three divergent species of Drosophila , including D. melanogaster . The results of this study uncovered two additional wasp species that are susceptible to Spiroplasma and two that are unaffected by Spiroplasma , implying at least two instances of loss or gain of susceptibility to Spiroplasma among larval parasitoids of Drosophila . Several strains of Spiroplasma , a heritable bacterium of Drosophila , were known to prevent development of three parasitoid wasps of Drosophila . Herein, we discover parasitoid wasps of Drosophila that are resistant to Spiroplasma , as well as additional wasps that are susceptible to Spiroplasma . The phylogenetic patterns of the wasps indicate multiple origins of resistance (or susceptibility) to Spiroplasma .
Electronic ISSN:
2045-7758
Topics:
Biology
Permalink