Paleontology (/ ˌpeɪliɒnˈtɒlədʒi, ˌpæli -, - ən -/ PAY-lee-on-TOL-ə-jee, PAL-ee-, -ən-), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to the start of the Holocene epoch (roughly 11,700 years before present).