 Phylogenetic biogeographic analysis of Early Cambrian Olenellidae and Redlichiidae suggests that a uniform trilobite fauna existed over Laurentia, Gondwana, and Siberia before the tectonic breakup of the supercontinent Pannotia between 600 and .Tectonic breakup of Pannotia then allowed for the diversification and radiation expressed later in the Cambrian as the distinctive Olenellid province (Laurentia, Siberia, and Baltica) and the separate Redlichid province (Australia, Antarctica, and China).Breakup of Pannotia significantly antedates the first appearance of trilobites in the fossil record, supporting a long and cryptic development of trilobites extending perhaps as far back as or possibly further back in time.