Dispersal in isolated systems and its influence on evolution: penguins and their ticks

Dispersal is key to many evolutionary processes. Host-parasite systems are unique in that the host often represents the parasite’s habitat, as well as its transportation. The interaction can be combative, and so specialisation is often extreme in parasitic species. Arguably one of the most impressive examples of parasitic adaptation is a terrestrial parasite that exploits a marine host. Penguins disperse by swimming but are bitten by terrestrial ectoparasites when they come ashore to breed. The most common of these is the tick (Ixodes spp.). In order to disperse with hosts, penguin ticks must be able to survive both on land and at sea. Here, we used a number of methods to explore the likelihood and extent of tick movements in association with their penguin hosts in Australia, New Zealand and the sub-Antarctic. Our results speak to the intertwined evolutionary and adaptive histories of hosts and their parasites.

About the speaker

Katie completed a Bachelor of Medical Science in 2010 at the ANU. Following the completion of her degree, she worked at the Commonwealth Department of Environment for a number of years. During this time, she was able to undertake a number of varied tasks focussed on environmental policy, including both its creation and application. In 2013, she returned to the ANU to undertake an Honours year, supervised by Ceridwen Fraser and Sam Banks. Her project employed genetic techniques to map the movements of ticks associated with little penguins (for which she received a First Class). Katie began a PhD in 2014 supervised by Ceridwen Fraser and cosupervised by Steven Chown (based at Monash University).