Study sequenced genomes from nearly 120 Philippine ethnic groups. Ayta Magbukon show top Denisovan ancestry levels worldwide. Denisovans form extinct human subspecies. Denisovan remains found in Siberian cave. Subspecies identified just a decade ago. Neanderthals better studied than Denisovans. Ayta Magbukon outpace all other groups in Denisovan admixture.