Going south for the summer

Many birds migrate each year to avoid the harshest cold of winter and hottest heat of summer. Globally, on longer time scales, most other animals and plants try to do the same, tracking the most suitable environmental conditions as the climate changes.

Through her genetic research on a wide range of species – from seaweeds and mosses to insects and parasites – Dr Crid Fraser has been studying how species have responded to past climate change by shifting their distributions, and how large barriers (such as oceans) affect their ability to disperse.

For example, Crid’s team have been using genetic approaches to find out whether penguin parasites (ticks, fleas and lice) can travel across oceans with their swimming hosts.

Crid’s team is also investigating whether volcanoes could have provided ice-free land for species to shelter on among glaciers during past ice ages, by looking at patterns of genetic diversity in relation to the locations of volcanoes in Antarctica.

With global warming, many of Australia’s species are heading southward or to higher altitudes in search of cooler climates. Those that are already only in the far south of the country, or found only high up on mountains, have limited options for dispersal, unless they can fly, swim, or otherwise travel long distances. Crid’s research will help us to work out which species are likely to be able to get around on their own, and which might need our help to shift to cooler climes.

Dr Ceridwen (Crid) Fraser