Pikaia! (TV) Opening Chorus Segment (2015 OP)brFósiles de cordados y cefalocordados del cámbrico. Por: Andrés David Arias Zambrano. Código:114675.brbrIf you wish to ask the question of the ages—why do humans exist?—a major part of the answer…must be: because Pikaia survived the Burgess decimation.