Conference Agenda

Parasites and their hosts engage in an ‘evolutionary arms race.’ As a parasite evolved tools to infect its host, the host will develop adaptations to evade infection. Microbiomes may also play key roles in the arms race between the two antagonists. We characterised the entire microbiome of parasite-host interactions, using the New Zealand native hairworms Gordius paranensis and Euchordodes nigromaculatus and their cave wētā hosts (Rhaphidophoridae) to investigate host and parasite microbiome overlap. Infected wētā, uninfected wētā, juvenile hairworms, and free-living mature hairworms all have microbiomes including viruses, bacteria, fungi, archaea and protists. We found that parasites harbour their own unique microbial taxa, in addition to microbes shared with infected wētā but not with uninfected wētā. This suggests hairworms do not rely on their host to develop a microbiome. As hairworms progress through their life stages, they exhibit a core microbiome; however, microbial community composition varies significantly across life stages, suggesting the environment has a significant effect on the parasite’s microbiome. Therefore, hairworm microbiomes are dynamic across the life cycle and modulated by the host and environment. The hairworm's diverse microbiome raises the intriguing possibility that its symbiotic microbes contribute to the iconic host manipulation (suicidal water-jumping) associated with hairworms.