Organisms take in carbon-14 naturally while they are alive, but when they die, they stop absorbing it.
Carbon-14 has a half-life of 5,000 years, so it slowly decays and its frequency declines as the organic material is buried.
Egyptologist Flinders Petrie (1853–1942) in 1899 developed the system of dating dependent on pottery styles.3 He proposed that Menes (aka Narmer, according to many authorities) ruled over a unified Egypt in 5500 BC.4 Egyptologist James Henry Breasted (1865-1935) dates Egypt’s unification under Menes to 3400 BC.5 In Centuries of Darkness, Peter James calls traditional chronology a “gigantic academic blunder.”6 Popular Egyptologist David Rohl writes, “The only real solution to the archaeological problems which have been created is to pull down the whole structure and start again, reconstructing from the foundations upward.”7 Egyptologists began to realize traditional chronology had serious issues when inconsistencies with Assyrian and Hittite discoveries surfaced.
Much progress revising Egyptian chronology has come from comparisons with other ancient cultures.
Radiocarbon dating of artifacts from Egypt’s Pre-dynastic period and First Dynasty, reported September 4th in the Proceedings of the Royal Society A by Michael Dee and colleagues, suggests Egypt is younger than previously thought.
“It ends up in crates in storage, but a lot of that is gold dust for radiocarbon dating.” Dee’s team chose bits of hair and bone as well as plant-based materials like seeds from granaries, reeds from baskets,8 and linen.Samples that produced results more than 1,000 years different from those expected were excluded.No result for the Pre-Dynastic periods older than 6500 BC or more recent than 2000 BC was included.Many bits of organic material carbon-dated in the latest study of Egypt’s First Dynasty originally came from these tombs.Image by Michael Dee, via NBC.10 The investigators statistically compared the results of radiocarbon testing on 74 new and 112 old specimens from Egypt’s Pre-Dynastic periods and First Dynasty with all the other archaeological data collected on those materials.This method only works to date organisms that were once alive no more than 58,000 to 62,000 years ago.