How Murray and Patsy Littlejohn Decoded Nature's Chorus
In the dead of night, armed with a homemade 17-kilogram recorder, two scientists set out to listen to the music of the frogs—and forever changed how we understand evolution.
Explore Their StoryImagine the Australian bush in 1954. As darkness falls, a chorus of croaks, whistles, and peeps erupts from ponds and creeks. To most ears, this is mere background noise. But to Murray Littlejohn and his wife and collaborator Patricia Gordon "Patsy" Littlejohn, these sounds contained evolutionary secrets waiting to be deciphered.
In an era before digital technology, Murray and Patsy became pioneers of bioacoustics—the study of sound in animal behavior—transforming how scientists understand frog communication, speciation, and evolution 7 .
Their work not only revealed new species but also uncovered the sophisticated language of frogs, where simple calls function as complex tools for attraction and territorial defense.
This is the story of how two persistent scientists heard music in amphibious murmurs and taught the world to understand the lyrics.
The Littlejohns' remarkable journey began at the University of Western Australia in 1953, when Murray's mentor, legendary naturalist Bert Main, suggested that frog calls might be scientifically important 7 . This simple observation sparked Murray's curiosity and set the direction for his life's work.
The first challenge was technological: how to properly document and measure these transient sounds? Their initial solution involved an ABC outside broadcasting van, a cathode-ray oscilloscope, and a continuous recording camera to film the sound waveforms 7 .
This cumbersome process eventually led Murray to commission a local dentist with precision machining skills to build a portable recorder based on schematics from a magazine article. The resulting contraption, based on a gramophone mechanism and weighed down with lead weights to maintain proper speed, tipped the scales at 17 kilograms—"only portable in the sense that it wasn't powered by mains power," Murray would later recall 7 .
Mentored by Bert Main at University of Western Australia - First introduced to the importance of frog calls 7
First frog recordings at Sheepwash Creek - Beginning of systematic bioacoustic studies in Australia 7
Completed PhD, began postdoctoral work in Texas - International collaboration and comparative studies 5
Joined University of Melbourne faculty - began 38-year tenure; extensive recording of Victorian frogs 5 7
Foundation President, Australian Society of Herpetologists - Established leadership role in Australian herpetology 5
Retired but continued research - Transitioned to Principal Fellow at University of Melbourne 5
Received ASRA Award for Excellence - Recognition for contributions to sound recording and preservation 8
Armed with this heavyweight technology, Murray and Bert Main began venturing into the cold evenings of south-west Western Australia. The operator of the heavy recorder would stay in the car while Murray ventured out with a microphone attached to a 50-meter cord, hunting for calling frogs 7 .
As the Littlejohns' work progressed, they discovered that frog calls were not just simple noises but complex signals with distinct functions. Their most fascinating revelations came from studying the Victorian smooth froglet (Geocrinia victoriana), whose call has two distinct parts: a "wark" and a series of "pip pip pips" 7 .
"Wark" + "Pip pip pips" = Complex Communication
Intrigued by this bi-phasic call, Murray and his team designed a clever field experiment to decode its meaning:
Female frogs moved consistently toward the "pip pip pips," identifying this as the mating attraction signal 7 .
Male frogs responded to the "wark" component by stopping their own calls and answering with more "warks"—indicating this functioned as a territorial signal directed at competing males 7 .
This elegant experiment demonstrated that the frog's call served dual purposes, essentially conveying both "I'm a male, come and get me" to females and "I'm a male, stay away" to other males 7 .
While Murray often received the public recognition, his wife Patsy was an integral part of their scientific team. Described as "an enthusiastic collaborator" in fieldwork, Patsy often operated the recording equipment during their largely nocturnal research 5 7 .
Her presence is permanently preserved in their scientific legacy—in some recordings, her voice can be heard in the background, a testament to her active participation 7 .
The Littlejohns' partnership extended beyond the field, with both being recognized together in scholarly publications that celebrated their joint contributions to herpetology 1 6 . Their collaborative approach to science exemplified how personal and professional partnerships can together advance human knowledge over decades.
A collaboration spanning six decades that advanced our understanding of frog communication and evolution.
Throughout their careers, the Littlejohns continuously adapted their research tools, moving from various reel-to-reel recorders to tapes, mini discs, and eventually digital technology 7 .
Homemade & Basic Equipment
Reel-to-Reel & Tape
Mini Discs
Digital Technology
Murray Littlejohn's contributions to science extended far beyond individual experiments. His work established bioacoustics as a crucial tool in evolutionary biology, demonstrating that frog calls provided measurable data for distinguishing species and understanding evolutionary relationships 7 . This was particularly valuable for identifying "cryptic species"—frogs that appear identical to the eye but represent distinct evolutionary lineages with different calls 7 .
Early recordings of the Heleioporus complex of frogs helped classify new species, including the whooping frog and hooting frog 7 .
As foundation President of the Australian Society of Herpetologists and head of the University of Melbourne's Zoology Department, he shaped Australian herpetology for decades 5 .
His work with "kindred spirit" Professor Frank Blair in Texas created important comparative studies of frogs across continents 7 .
Two amphibian species—Littlejohn's Toadlet and Littlejohn's Tree Frog—were named in his honor, a traditional scientific tribute to his contributions 8 .
Thousands of his recordings have been digitized and made accessible through Museums Victoria, ensuring their availability for future research 8 .
Years of Research
Recordings Preserved
Species Discovered
Perhaps most importantly, Murray Littlejohn recognized that his life's work had implications beyond pure science. In his later years, he worked to ensure his collection would be preserved and accessible, understanding that these recordings could play a "vital role in the ongoing effort to understand our unique and beautiful amphibian population so that we can better protect and preserve them" 8 .
Murray and Patsy Littlejohn taught us to listen to the natural world with more attentive ears. They showed that evolution composes its symphonies not just in physical form but in sound, and that understanding these acoustic signals reveals profound truths about how species evolve, communicate, and maintain their place in the world.
Today, as Murray listens to his old recordings on his computer in retirement, he would smile and call it "frog music" 7 . Indeed, through the Littlejohns' work, we have all learned to appreciate the complex compositions that echo through the night—each peep, warble, and wark a note in the grand evolutionary orchestra that they helped us understand.
Their partnership—in life and science—demonstrates how curiosity, persistence, and collaboration can decode nature's mysteries, transforming indiscriminate noise into understandable patterns that reveal the workings of evolution itself.