EddyMarsden2019The Royal Society Te Apārangi Marsden round of funding has just been announced yesterday, and Eddy has been successful with her application "Battle of the body snatchers: do multiple parasites in a host help or hinder each other?". Eddy has been working on parasites, namely hairworms, of insect hosts like the european earwig and cave wētā since she joined the Gemmell Lab (see our "Mind Controlling Parasites" page). During her research, Eddy and her collaborators would often find that there could be several hairworms - up to seven! - in a single insect host. Eddy found this intriguing, particularly when the multiple parasite hairworms were found to be at different developmental stages. Parasites routinely manipulate their hosts, imposing changes like altering the host's appearance and behaviour.

In the case of the cave wētā, mature parasites will induce its host to seek and dive into a body of water, effectivelly killing the wētā. At this stage, the mature parasites emerge from the drowned wētā to reproduce. But how do multiple parasites coordinate their host manipulation, in particular if they are not all at the same developmental stage? If at the time of the drowning of the wētā any undeveloped parasites are present, this will mean they will die, and only the mature parasites survive. If these immature parasites are to survive, they may work to delay the hosts manipulations by the mature parasites. Alternatively, it could be that closely related hairmworms found in the same host could sacrifice their own survival for that of a close relative.

These are the questions that Eddy will aim to answer, using a combination of behavioural science and molecular genetics tools.

More on Eddy's project can be found on the Marsden website.

Congratulations to Eddy on this fantastic achievement!