SYDNEY, April 1 (Xinhua) -- A study released on Wednesday has shown that male dolphins will coordinate their vocalizations in order to find a mate, proving another layer in the alluring mammals' complex social lives.
Researchers from the University of Western Australia and the University of Bristol used underwater microphones, called hydrophones, to record groups of dolphins in Shark Bay, Western Australia.
Lead author on the study, Bronte Moore told Xinhua that the project had been running for over 40 years, meaning that the team could easily identify individual dolphins by markings on their dorsal fins to determine who was socialising with who.
"The population of dolphins in Shark Bay have been shown to have one of the most complex social structure of any non-human species, featuring multi-level alliances among male bottlenose dolphins," she explained.
Moore said that the latest research further described how males in this population build strong, life-long relationships with other males.
The team recorded groups of male dolphins vocalising together using a series of "pops" which they would match in tempo, and maintain sometimes for up to 25 seconds.
Male dolphins were recorded making these coordinated noises when herding females for mating, an activity which usually occurred with a ratio of two or three males to one female.
"As only one of the three males is likely to father offspring under these circumstances, they may be using coordinated pops to reduce tension between themselves in order to cooperate in pursuing the female together, and increase their overall odds of reproducing," Moore explained.
"This reproductive strategy is a testament to their social complexity, as they are able to work together to secure females and increase the overall odds of reproducing, rather than taking an 'every man for himself' approach."
According to Moore, the relationships between the dolphins are complex, and similar to the way humans have close friends, outer friendship groups and then acquaintances.
"Loosely, we can say that in humans, synchronised actions lead to increased feelings of bonding, foster cooperation and diminish the perceived threat of rivals," Moore said.
While she hesitated to make any comparisons or judgements as to what is going on inside the minds of these large mammals, Moore added that, "the social complexity observed in this population would suggest that these animals are very intelligent."
