One sprouted. Scientists initially estimated its age at about 2000 years old based on carbon dating of other seeds found at the site, but they had no way of directly testing the planted seed without risking its chance of survival.

After the Methuselah seed germinated, Dr Solowey found fragments of the seed shell clinging to the roots  enough for dating.

The fragments initially dated to AD295, give or take 50 years, but a small percentage of "modern" carbon incorporated as the seed germinated made it appear 250 to 300 years younger. Correcting for this factor, the researchers reported that the seed dated from 60BC to AD95, similar to the other seeds from the site. That placed the seed at Masada around the Roman siege in the year 73, when, according to the ancient historian Josephus, nearly 1000 Jewish Zealots in the fortress committed mass suicide rather than capitulate to the Romans.

They burned most of their food stores, leaving a single cache to show that they did not starve to death.

"These people were eating these dates up on the mountain and looking down at the Roman camp, knowing that they were going to die soon, and spitting out the pits," Dr Sallon said. "Maybe here is one of those pits." Archaeologists excavating the fortress of Masada originally unearthed the seeds in 1965.