An article published in Chemical & Engineering News said the average age at which Nobel laureates in chemistry, physics and physiology or medicine do their prize-winning work is increasing.
Most Nobel prizes in chemistry since 1960 have been awarded for work done after the laureate's 40th birthday, while between 1901 and 1960 work done before age 40 predominated, a release by the American Chemical Society said.
The researchers suggest younger scientists are spending more time getting advanced doctoral degrees and in temporary research positions afterward.
Also, there has been a transition from awarding prizes for theoretical research, which favors younger scientists, to that based on extensive experiments, which favors older scientists, they said.
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