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Academia is a small world and just how small was brought home to Professor Shane Maloney from the School of Anatomy, Physiology and Human Biology two years ago. He has always enjoyed working in South Africa, having spent three years as a post-doc at the University of the Witwatersrand in Johannesburg in the early 1990s, where he did some work on temperature regulation in ostriches.

In February 2008, his colleagues at Witwatersrand asked him if he would help a team from the Max Planck Institute for Ornithology undertake a study in South Africa on sleep in ostriches.

At about the same time, he received an email from a Canadian named John Lesku wanting to do a post-doc in comparative physiology at UWA.

After two or three weeks and several emails going each way, it became clear that John was one of the researchers from Max Planck wanting to work on ostriches, but John wasn’t aware that Shane was part of the Witwatersrand team.
The outcome of those emails and a field trip to the African bush has been a paper in the prestigious online science journal PLoS One and a UWA Post-doctoral fellowship for Dr John Lesku, beginning in 2012. John will work with Shane,
as well as Professor Peter Eastwood in the new Centre for Sleep Science , and Professor Don Robertson in the Neurophysiology lab.

John is interested in the evolution of sleep, a curious state in which every animal engages despite the inherent vulnerability of sleeping. There are lots of theories, but no consensus, on why we sleep. Since sleep states don’t fossilise, John wants to use a comparative approach to look at sleep in different groups of living animals to see how it has changed in evolutionary time.

Most mammals engage in two types of sleep, slow wave sleep (SWS) and rapid eye movement (REM) sleep.

The most basal (or “ancient”) group of living mammals – the egg-laying monotremes – engage in a REM sleep state that combines aspects of SWS (large, slow brainwaves) and REM sleep (rapid eye movements and reduced muscle tone). Whether this reflects an early stage in the evolution of mammalian sleep or a derived feature of monotreme biology is unclear.

Interestingly, birds are the only non-mammals to engage in SWS and REM sleep.

To determine the significance of the mixed state of monotremes, John and Shane conducted the first electrophysiologically-based study of sleep in the ostrich, a member of the most basal group of birds, the Palaeognathae.

They found that ostriches engage in unequivocal SWS; however, their REM sleep, reminiscent of monotremes, combined aspects of REM sleep and SWS. This observation suggests that the pattern of brain activity that characterises REM sleep in more derived mammals, including humans, is an evolutionary new feature of sleep that may support new sleep functions not found in more “ancient” animals.

John will use his post-doc to study sleep in the wild in other “old” mammals and birds, including monotremes and emus.