Professor Benno Torgler, of the Queensland University of Technology in Brisbane, and colleagues compared the behaviour of individuals on the ill-fated RMS Titanic and RMS Lusitania passenger ships.
The Titanic sank after hitting an iceberg in the Atlantic in 1912 and the Lusitania was torpedoed by a German U-boat off the Irish coast in 1915.
The researchers found that the social norm of “women and children first” was deferred to only on the Titanic, where first class passengers also had a higher probability of survival.
Professor Torgler says this contrasts to the situation on the Lusitania, which favoured survival of the fittest.
“There were substantial behavioural differences on the Lusitania,” he said.
“Those with the best chance of survival were aged 16 to 35, with little difference between genders (10.4 per cent females versus 7.9 per cent for males) and first class passengers actually fared worse.
“This suggests that competition was the strongest driving factor influencing survival.”
The Titanic and Lusitania were chosen for the study because of the availability of individual passenger crew data, the similar passenger demographics and the historical timing of the disasters.
Co-author David Savage said the mean survival rate, age, proportion of women, and class of passenger were almost identical.
“The similarities between the two vessels are uncanny,” he said.
“Given that the two events occurred within a couple of years of each other we can also assume that the social norms or manners were unchanged.”
What differed between the two events was time.
The Titanic took 2 hours and 40 minutes to sink after its collision with an iceberg, whereas the Lusitania was completely submerged 18 minutes after being hit by a German torpedo.
“The shortened disaster time favoured instinctive fight-or-flight behaviour, whereas the lengthier disaster led to the appearance of social norms,” Professor Torgler said.
“We know the first is driven by the rush of adrenalin to the brain, but we don’t know exactly when the altruistic behaviour takes over.
“These are true preferences revealed only in test conditions, they aren’t something you can accurately assess by surveying responses to hypothetical situations.”
Previously, the researchers had noted that British passengers on the Titanic were less likely to survive than all other nationalities.
“This had suggested that English manners were a disadvantage in a life-and-death situation, but on the Lusitania, these cultural differences didn’t seem to make much difference to a passenger’s chance of survival,” Mr Savage said.
The group are now looking at human behaviour in risky activities such as mountaineering, as well as other tragedies such as the September 11, 2001 terrorist attacks in the United States and the Australian bushfires.
Knowing how individuals and groups make decisions helps to shape policy for disaster situations.
“There’s a fine line between crowding out naturally good behaviour and creating policy that has a positive impact on survival outcome,” Mr Savage said.
The research will be published in this week’s Proceedings of the National Academy of Sciences.