The Sleep Ecophysiology Group studies sleep behaviour and neurophysiology in diverse animals, including birds and mammals, reptiles and fishes, and invertebrates, often in naturalistic or wild environments. Using this strong comparative approach that integrates behavioural ecology with neuroscience, we aim to provide insight into:
(I) The evolution of sleep and sleep states
(II) The causes and consequences of inter- and intra-specific variation in sleep duration
(III) Animals that forgo sleep when competing demands favour extended wakefulness
(IV) The role of ecological factors, such as predation risk, in determining where, when and how long animals sleep
(V) Local aspects of sleep
(VI) Sleep-dependent cognition in birds
(VII) The effects of pollution (light and sound) on sleep in birds
The research interests of each group member can be found below.
I’m interested in most things related to sleep. Using behavioural observations, accelerometry for remote monitoring and neurophysiological recording techniques, I seek to provide insight into how sleep and sleep functions have evolved in different types of animals, from flatworms to birds and mammals. I also study how ecological factors (e.g., predation risk, reproduction) influence the amount, composition, depth and timing of sleep. Most recently, these interests have expanded to include how anthropogenic light pollution influences sleeping brain activity in mammals (with Dr Kylie Robert) and birds (with Dr Therésa Jones).
I completed my B.Sc. in zoology at the University of Guelph (Canada) in 2002. I then did a MSc with Drs Charles Amlaner and Steven Lima at Indiana State University (USA) (2003-2006). This work consisted mostly of phylogenetic comparative analyses of sleep quotas as a means for testing interspecific support for various non-exclusive hypotheses for the functions of sleep. These, and other, studies provided evidence that the risk of predation can reduce the amount of rapid eye movement (REM) sleep over both evolutionary and ecological timescales, in prey. From there I joined the Avian Sleep Group of Dr Niels Rattenborg at the Max Planck Institute for Ornithology – Seewiesen (Germany). My PhD focused on the evolution and regulation of sleep states in birds (2007-2011). I stayed in Seewiesen for the remainder of 2011 as a postdoc – a part of what has been the most fulfilling collaboration of my career. Working with Drs Rattenborg and Mihai Valcu, and Prof Dr Bart Kempenaers, we studied breeding pectoral sandpipers on the tundra in Barrow, Alaska; work that provided the first direct evidence that sleep loss can be evolutionarily adaptive. For my contributions to this group effort, I was given the Young Investigator Award by the Sleep Research Society (USA). After 5 wonderful years in Germany, I took up a University Postdoctoral Research Fellowship at The University of Western Australia (2012). Soon thereafter I was offered a continuing position at La Trobe University, which I commenced in 2013. From 2014-2017, I was an Australian Research Council (ARC) Discovery Early Career Researcher Award (DECRA) Research Fellow. In December 2016, I was promoted to Senior Lecturer.
Anne Aulsebrook – Impacts of streetlights on sleep in urban birds
Increasing artificial light at night (ALAN) is one of the most rapid and pervasive changes to our natural environment. Nevertheless, the consequences of ALAN for wildlife are only beginning to be understood. A likely impact of ALAN is the disruption of endogenous daily rhythms, or circadian rhythms, including the sleep-wake cycle. My research investigates the impacts of ALAN on the circadian rhythms of two urban bird species, the black swan (Cygnus atratus) and the pigeon (Columba livia). Wild swans at Albert Park Lake are well-studied, individually identifiable, exposed to artificial night lights, and ideal for investigating impacts of ALAN in a natural or semi-natural environment. Meanwhile, pigeons are an ideal model species for studying the impacts of ALAN in a more controlled, laboratory setting. My project is co-supervised by Prof Raoul Mulder and Dr Therésa Jones at The University of Melbourne.
Robin Johnsson – Ecologically relevant sleep-dependent cognition in birds
Sleep is important for maintaining optimal performance during wakefulness. The dominant venue for sleep research is the laboratory, with a clear focus on the study of inbred strains of rat and mouse. Most work on the role of sleep in memory processing and performance is conducted with mazes and motor-vigilance tasks. However, (a) the laboratory is an overly simplified environment that fails to capture the complexity of natural conditions, (b) inbred rodents themselves are simplified animals, and (c) the cognitive tests used have limited ecological relevance. Little is known about how animals use sleep for maintaining cognitive abilities in the wild.
Advanced cognition is a key trait enhancing the fitness of many wild animals. Maintaining the neural mechanisms for advanced cognition, including specialized memory, is energetically expensive, and is critically dependent on sleep. In addition, sleep also imposes missed-opportunity costs on animals by limiting the time available to perform alternative behaviours. In my PhD, I will study the ecological role of sleep in the lives of birds in Australia and in the USA working with Dr Timothy Roth at Franklin & Marshall College and Prof John Endler at Deakin University.
Michael Kelly – The behavioural and physiological indicators of sleep in sharks
Sleep is a conspicuous behaviour in the lives of most animals, and is intimately tied to activity patterns, circadian rhythms and changes in metabolic rate. Sleep is of great importance to us as humans and is found in all terrestrial vertebrates and many invertebrates studied so far. However, questions of whether, how and when, many aquatic animals, including sharks, engage in this enigmatic behavioural and physiological state remains unclear.
My dissertation aims to answer these long standing questions by integrating investigations of behavioural patterns of inactivity, circadian rhythms, and the influences of environmental factors, with the assessment of physiological indicators of sleep (heart and respiratory rates, muscle tone) and recordings of brain activity in sharks. I will search for signs of sleep in representatives of benthic sharks (buccal pumping species which can remain motionless on the sea floor for extended periods of time) and pelagic species (ram ventilating sharks) that must swim continuously to keep water flowing over their gills. Overall, this comprehensive and multidisciplinary approach will help characterise sleep in sharks for the first time and provide new insights into sleep evolution and how the physiological demands associated with different respiratory strategies influence if and how sharks obtain their daily sleep. I am co-supervised by Prof Shaun Collin at La Trobe University and Dr Jan Hemmi at The University of Western Australia, Perth.
Shauni Omond – Sleep evolution: pharmacological, neurochemical and comparative perspectives
Sleep is a much-studied behaviour across animals, with humans spending roughly one-third of their lives in this vulnerable state. But where did it all start? My research looks at the evolutionary origins of sleep. My main research animal is platyhelminth flatworms – a phylum that appeared 800 million years ago, to determine if the processes that maintain and regulate sleep in humans is shared across distantly-related animals. To do this, I use a combination of behavioural, pharmacological, biochemical, and electrophysiological techniques. As well as looking at flatworms, I examine the phylogenetic breadth of sleep, through the study of animal phyla previously unstudied with respect to sleep. Collectively, these studies will provide insight into when, why, and how sleep first appeared. I am co-supervised by Assoc Prof Bruno van Swinderen at The University of Queensland and Assoc Prof Martin Steinbauer and Dr Matthew Hale at La Trobe University.
Erika Zaid – Reproductive sleeplessness in dasyurid marsupials
Sleep is a prominent part of animal life, but our understanding of the adaptive value of sleep remains incomplete. Even though it is generally thought that reduced performance is an inevitable outcome of sleep loss, some animals may perform well on little sleep when ecological demands favour extended periods of wakefulness. One of the best mammal candidates for such sleeplessness is antechinus, as these marsupials die synchronously after just one intense mating season. My project, based in the Otways, examines the activity patterns of dusky antechinus in a real-world environment in and outside the breeding season, and quantifies the concentration of various hormones that may predict activity levels. Furthermore, to provide insight into sleep evolution and function, my research seeks to determine relatedness among animals to see whether the most active males sire more offspring. I am co-mentored by Dr Kylie Robert also at La Trobe University and Dr Peter Meerlo at the University of Groningen in The Netherlands.
None at present.
Former Honours Students
Brayden J. Redwood – Increased activity of dusky antechinus (Antechinus swainsonii) males during the breeding season
Chris Vapp – Effects of decapitation and regeneration on the activity patterns in planaria flatworms (Girardia tigrina)
Linh Ly – Activity patterns in jellyfish
Shauni Omond – Searching for sleep in an evolutionarily simple bilaterian