Women and children came first when the Titanic sunk but not when the Lusitania was torpedoed, a study has claimed.
The difference in behaviour was due to the speed at which the two maritime disasters struck, researchers said.
The Titanic took more than two hours to sink when it hit an iceberg four days into its maiden voyage from Southampton to New York, on 14 April, 1912.
But the liner Lusitania sank in 18 minutes in 1915 when it was torpedoed by a U-boat during World War One.
The passenger ship was heading for Liverpool from New York when it was sunk by the German submarine off the Irish coast with the loss of nearly 1,200 lives.
Both historic tragedies involved similar vessels, passenger populations and death tolls.
But in the case of the Titanic, it was a case of "women and children first" in the best maritime tradition, according to researchers writing in the journal Proceedings of the National Academy of Sciences.
"We are interested in peoples behaviour under various circumstances, to look at how behaviour varies under conditions of life and death," said Bruno Frey, professor of economics at the University of Zurich in Switzerland, who led the research.
'Selfish behaviour dominated'
A study of the disaster showed that females, children and people accompanying a child were more likely to survive than males, adults and passengers without children.
Of the 2,207 passengers and crew on board the ship when it set sail, all but 690 perished.
Children on the Titanic had a 14.8% higher chance of surviving than adults and a person accompanying a child was 19.6% more likely to survive than someone without a child.
Being female increased a passenger's chance of survival by more than 50%.
In contrast, fit passengers aged 16 to 35 stood the greatest chance of surviving from the Lusitania disaster.
Among the 1,949 passengers and crew on the Lusitania, there were 636 survivors.
Time pressure seems to have been key in determining who lived and who died. The study says that on the Lusitania, selfish behaviour dominated and on the Titanic, social norms and social status (class) dominated, contradicting standard economics.
"One of the major implications is that people really do behave differently when they are under enormous stress. Then the animal-like aspects and survival of the fittest really come to the fore," said Professor Frey.
"When the Titanic hit the iceberg the norms upheld themselves surprisingly well. Many people think that when there is a disaster, a natural hurricane or whatever, everything breaks down, there is chaos and the norms do not apply any more.
"But it's only when they are under extreme duress: there's an explosion on the ship, the torpedo hits and you are in the water, then survival of the fittest becomes active but not otherwise," he said.
While first class passengers on the Titanic were more likely to find a place in a lifeboat, higher social status proved to be no advantage on the Lusitania, the study found.