A man who donated a kidney to his dying twin brother 56 years ago in the world's first successful organ transplant has died aged 79.
Ronald Lee Herrick died on Monday in hospital in Maine after undergoing heart surgery in October.
Mr Herrick donated a kidney to his twin brother, Richard. Because they were identical twins, there was no problem with rejection.
The operation on December 23, 1954, kept Mr Herrick's brother alive for eight years. Lead surgeon Dr Joseph Murray went on to win a Nobel Prize.