The Cambrian is the first geological period of the Paleozoic Era, lasting from 542 ± 0.3 to 488.3 ± 1.7 million years ago (mya) (ICS, 2004); it is succeeded by the Ordovician. Its subdivisions, and indeed its base, are somewhat in flux. The period was established by Adam Sedgwick, who named it after Cambria, the Latin name for Wales, where Britain's Cambrian rocks are best exposed. The Cambrian is unique in its unusually high proportion of lagerstätten. These are sites of exceptional preservation, where 'soft' parts of organisms are preserved as well as their more resistant shells. This means that our understanding of the Cambrian biology surpasses that of some later periods.

The Cambrian Period marked a profound change in life on Earth; prior to the Cambrian, living organisms on the whole were small, unicellular and simple. Complex, multicellular organisms gradually became more common in the millions of years immediately preceding the Cambrian, but it was not until this period that mineralised – hence readily fossilised – organisms became common. The rapid diversification of lifeforms in the Cambrian, known as the Cambrian explosion, produced the first representatives of many modern phyla, representing the evolutionary stems of modern groups of species, such as the arthropods. While diverse life forms prospered in the oceans, the land was comparatively barren – with nothing more complex than a microbial soil crust. Most of the continents probably resembled deserts.^{[citation needed]} Shallow seas flanked the margins of several continents created during the breakup of the supercontinent Pannotia.The seas were relatively warm, and polar ice was absent for much of the period.

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.

Charles Hardin Holley (September 7, 1936 – February 3, 1959), known professionally as Buddy Holly, was an American singer-songwriter and a pioneer of rock and roll. Although his success lasted only a year and a half before his death in an airplane crash, Holly is described by critic Bruce Eder as "the single most influential creative force in early rock and roll." His works and innovations inspired and influenced contemporary and later musicians, notably The Beatles, Elvis Costello, The Rolling Stones, Don McLean, Bob Dylan, and Eric Clapton, and exerted a profound influence on popular music. Holly was among the first group of inductees to the Rock and Roll Hall of Fame in 1986. In 2004, Rolling Stone ranked Holly #13 among "The Fifty Greatest Artists of All Time".

Charles Hardin Holley was born on September 7, 1936, in Lubbock, Texas, to Lawrence Odell and Ella Pauline (Drake) Holley. In Philip Norman's biography it is stated that his mother's family claimed to be descended from the English navigator Francis Drake.