<P> Geometric designs on pottery of the eighth century BC depict scenes from the Trojan cycle, as well as the adventures of Heracles . These visual representations of myths are important for two reasons . Firstly, many Greek myths are attested on vases earlier than in literary sources: of the twelve labors of Heracles, for example, only the Cerberus adventure occurs in a contemporary literary text . Secondly, visual sources sometimes represent myths or mythical scenes that are not attested in any extant literary source . In some cases, the first known representation of a myth in geometric art predates its first known representation in late archaic poetry, by several centuries . In the Archaic (c. 750--c. 500 BC), Classical (c. 480--323 BC), and Hellenistic (323--146 BC) periods, Homeric and various other mythological scenes appear, supplementing the existing literary evidence . </P> <P> Greek mythology has changed over time to accommodate the evolution of their culture, of which mythology, both overtly and in its unspoken assumptions, is an index of the changes . In Greek mythology's surviving literary forms, as found mostly at the end of the progressive changes, it is inherently political, as Gilbert Cuthbertson has argued . </P> <P> The earlier inhabitants of the Balkan Peninsula were an agricultural people who, using Animism, assigned a spirit to every aspect of nature . Eventually, these vague spirits assumed human forms and entered the local mythology as gods . When tribes from the north of the Balkan Peninsula invaded, they brought with them a new pantheon of gods, based on conquest, force, prowess in battle, and violent heroism . Other older gods of the agricultural world fused with those of the more powerful invaders or else faded into insignificance . </P> <P> After the middle of the Archaic period, myths about relationships between male gods and male heroes became more and more frequent, indicating the parallel development of pedagogic pederasty (eros paidikos, παιδικὸς ἔρως), thought to have been introduced around 630 BC . By the end of the fifth century BC, poets had assigned at least one eromenos, an adolescent boy who was their sexual companion, to every important god except Ares and to many legendary figures . Previously existing myths, such as those of Achilles and Patroclus, also then were cast in a pederastic light . Alexandrian poets at first, then more generally literary mythographers in the early Roman Empire, often re-adapted stories of Greek mythological characters in this fashion . </P>

Who wrote parallel lives of greek and roman mythic and historic figures