Toronto, Jan 31 : Natural disasters seem to bring out the best in older children, prompting even nine-year-olds to become more sharing, just as six-year-olds turn more selfish, says a study.

The findings are based on a rare natural experiment in China by researchers at the universities of Toronto, Chicago and Liaoning Normal around the time of a horrific earthquake. A crucial difference between the two age groups emerged one month after the disaster.

The six-year-olds' willingness to share in a test measuring altruism dropped by a third, while among nine-year-olds, willingness to give to others nearly tripled. Three years later, children in the age groups returned to pre-earthquake levels of altruism, the journal Psychological Science reports.

"The study provides the first evidence to suggest that experiencing a natural disaster affects children's altruistic giving significantly. The immediate negative effect of the earthquake on six-year-olds suggests that altruism at that age is still fragile," said Kang Lee, professor at the University of Toronto, according to a statement from the varsity.

"We think that empathy is the intervening variable," said Jean Decety, professor of psychology and psychiatry, University of Chicago and study co-author. The study demonstrates the developmental differences in the growth of empathy, Decety said.

"Even with the group of nine-year-olds, we show that not only are they more altruistic and give more than the six-year-olds, but those nine-year-olds with higher empathy scores donated significantly more than nine-year-olds with lower scores," Decety added.

In early 2008, the researchers were in Sichuan, China, working on a study on empathy and altruism among children and had completed the first portion of it. In May 2008, an earthquake struck the region and killed 87,000 people.

The team immediately decided to change the course of their study and explore what the experience of a disaster might mean to the children's concern for others. (IANS)