Generally, comparative research about animal personalities has always focussed on primates. “So we decided,” said Dr Blake Morton, lead author of this new study, “to do something different and look at dolphins. No one’s ever studied personality in dolphins before in the way we have.”
Scientists found dolphins to be curious and sociable, and possess a blend of extraversion and agreeableness
In 2012, Morton’s team began their study of 134 male and female bottlenose dolphins from eight facilities in regions including Mexico, France, the Cayman Islands and the US. It was published in the Journal of Comparative Psychology this year, with the overall conclusion that dolphins fit our human definitions of personality.
It may be misinterpreted that humans and dolphins have the same personality traits – they don’t. It’s just that some of them are similar
A common scientific way of defining personality uses, appropriately, the acronym OCEAN. It defines our five central personality traits as spectrums of Openness (i.e. curiosity), Conscientiousness (i.e. self-control, reliability), Extraversion (i.e. sociability), Agreeableness (i.e. kindness), and Neuroticism (i.e. anxiety, emotional instability).
When scientists applied that model to dolphins, they found dolphins to be curious and sociable, and to possess a blend of extraversion and agreeableness. Neuroticism, however, was not found in significant levels in the dolphins investigated by the study.
Speaking about the study, Dr Morton has said, “I don’t want people to misinterpret that and say humans and dolphins have the same personality traits – they don’t. It’s just that some of them are similar.”
He explained that, “Dolphins, like many primates, have brains that are considerably larger than what their bodies require for basic bodily functions; this excess of brain matter essentially powers their ability to be intelligent, and intelligent species are often very curious.”
The curiosity of bottlenose dolphins manifests in startlingly human-like behaviours: they have been documented surfing, which Sir David Attenborough says they do “to strengthen friendships, develop social skills, and for the sheer exhilaration of it."
They have also been filmed passing pufferfish around among themselves and getting high on the toxins released by the fish.
But this study also has implications for how we understand ourselves: “Scientists still do not fully understand why our behaviour comes down to those five traits, so one way of doing that is to compare ourselves to other animals – what we share in common and why,” said Dr Morton.
Although dolphins remain a species in the category of ‘least concern’ of extinction, they are being affected by climate change. A recent study found that a 2011 heatwave had much more of an impact on dolphins than previously thought - but the dolphins who were adept at using tools were the least affected, suggesting the intelligence and human-like attributes of dolphins could be what keeps them alive in the dangerous years to come.