The Precambrian (Pre-Cambrian) is the name which describes the large span of time in Earth's history before the current Phanerozoic Eon, and is a Supereon divided into several eons of the geologic time scale. It spans from the formation of Earth around 4600 Ma (million years) ago to the beginning of the Cambrian Period, about 542 Ma, when macroscopic hard-shelled animals first appeared in abundance. The Precambrian is so named because it precedes the Cambrian, the first period of the Phanerozoic Eon, which is named after Cambria, the classical name for Wales, where rocks from this age were first studied. The Precambrian accounts for 88% of geologic time.

Not much is known about the Precambrian, despite it making up roughly seven-eighths of the Earth's history, and what little is known has largely been discovered in the past 50 years. The Precambrian fossil record is poor, and those fossils present (e.g. stromatolites) are of limited biostratigraphic use. This is because many Precambrian rocks are heavily metamorphosed, obscuring their origins, while others have either been destroyed by erosion, or remain deeply buried beneath Phanerozoic strata.

Sir David Frederick Attenborough ( /ˈætənbərə/) OM, CH, CVO, CBE, FRS, FZS, FSA (born 8 May 1926) is a British broadcaster and naturalist.

His career as the face and voice of natural history programmes has endured for more than 50 years. He is best known for writing and presenting the nine Life series, in conjunction with the BBC Natural History Unit, which collectively form a comprehensive survey of all life on the planet. He is also a former senior manager at the BBC, having served as controller of BBC Two and director of programming for BBC Television in the 1960s and 1970s.

Attenborough is widely considered a national treasure in Britain, although he himself does not care for the term. He is a younger brother of director, producer and actor Richard Attenborough.

Attenborough was born in Isleworth, west London, but grew up in College House on the campus of the University College, Leicester, where his father, Frederick, was principal. He is the middle of three sons (his elder brother, Richard, became an actor and his younger brother, John, an executive at Italian car manufacturer Alfa Romeo). During World War II his parents also adopted two Jewish refugee girls from Europe.