It takes time to get yourself into a self-sacrificing frame of mind, according to research into the sinking of the Titanic and the Lusitania.
Behavioural economists from Queensland University of Technology have concluded that the social norm of protecting women and children came into play when there was time to organise - but that when time was critical it was a case of survival of the fittest.
Professor Benno Torgler of QUT's School of Finance and Economics and his research team compared the survival demographics of the 1912 sinking of the Titanic, where 1,517 people died, with the 1915 torpedoing of the passenger ship the Lusitania in which more than 1,198 people died.
In both disasters, the captains issued orders to officers and crew to follow the social norm of 'women and children first'. It seems these orders were successfully carried out on the Titanic, but not on the Lusitania.
"Time is the key," Professor Torgler said. "It seems the innate fight or flight mechanism comes into play when time is of the essence because the Lusitania sank in just 18 minutes and most survivors were young, fit people aged 16 to 35.
"In contrast, males in their prime had a lower chance of surviving the Titanic. We found that on the Titanic children had a 14.8 per cent higher probability of surviving than a man and a person accompanying a child had a 19.6 per cent higher chance while a woman had a 50 per cent higher chance. But the Titanic took two hours and 40 minutes to finally disappear beneath the sea."
Professor Torgler said the figures show that people's behaviour in disasters does not follow the traditional mythology of mass panic.
"On the Lusitania, selfish behaviour prevailed which corresponds to the economic tenet that maximising self-interest is the key motivator of behaviour," he said. "By contrast, on the Titanic, more time meant there was time for social norms and social class to kick in."