Researchers at The University of Western Australia have been studying the unique communication methods of young coral reef fish to learn more about how animals “talk” to each other.
Combining laboratory work and field-based experiments on the Great Barrier Reef, scientists looked at when and under what conditions juvenile damselfish developed ultraviolet (UV) facial patterns to communicate vital information to each other while remaining undetected by potential predators.
Research Associate Professor Monica Gagliano, from UWA’s Centre for Evolutionary Biology, said the study found young fish were unable to develop the UV facial patterns used as invisible communication channel unless they were surrounded by their natural environment.
“These baby fish are under tremendous pressure from predators so their first “words” are most likely going to be important ones, ones that enhance survival,” Associate Professor Gagliano said.
“Consequently, we expected that all fish would develop these UV markings at a young age and that their development was “hard-wired”, but to our surprise we found that the markings only developed when fish were exposed to their natural environment on the reef.”
Funded by an Australian Research Council grant and published in the journal Scientific Reports, the study was carried out with the Australian Institute of Marine Science and the University of Queensland.
Dr Martial Depczynski from the Australian Institute of Marine Science said the researchers put lab-based fish under a whole range of different feeding and social conditions to exclude everything else that was important to young fish at this critical stage of their lives.
“The next obvious study is to see if exposure to predators in a lab-based environment is enough to trigger the markings,” Dr Depczynski said.
“Understanding what and how much animals are able to communicate to each other is one of science’s most intriguing mysteries,” Associate Professor Gagliano said.
“Because there are so many predators on a coral reef and life is so risky for baby fish, the ability to communicate danger is the most likely explanation for the absence of UV markings in our lab experiments and why they develop them so quickly on the reef.”
The research had major implications for our understanding of the role of structural colouration in animals, Associate Professor Gagliano said.
“Traditionally, UV colour has been studied in the context of mate selection but these fish are not only sexually immature, but they are also all born female suggesting that these colours have a different function at this early stage in life, one that may change as fish get older,” Associate Professor Gagliano said.
“Regardless, it seems that UV signalling may convey a whole range of different information and we are just touching the tip of the iceberg with this research.”
David Stacey (UWA Media and Public Relations Manager) (+61 8) 6488 3229 / (+61 4) 32 637 716
Monica Gagliano (UWA School of Animal Biology) (+61 8) 6488 1361
Martial Depczyski (Australian Institute of Marine Science) (+61 8) 6369 4025
Ulrike Siebeck (University of Queensland) (+61 7) 3365 4070