Final answer:
Similar stories and themes in world literature are a result of cultural diffusion, where cultural beliefs and social activities spread across different groups, sharing myths, stories, and traditions globally.
Step-by-step explanation:
The occurrence of similar stories and themes across different cultures and literature is largely attributable to cultural diffusion. This process involves the spreading of cultural beliefs and social activities from one group to another. The mixing of world cultures through various means, including trade, migration, and indeed, the more somber history of colonization, has resulted in the blending and sharing of myths, stories, and traditions. Through cultural diffusion, aspects of religion, morality, and societal roles have been interwoven into the literature of different civilizations, manifesting in similar narratives and themes globally.
Origin stories are a prime example of how cultural diffusion has contributed to shared themes in literature, as they often serve to explain a group's place in the world, promote a common cultural identity, and create a collective understanding of human existence. The widespread presence of such stories in world literature suggests that despite cultural differences, human societies share common questions and themes that are explored through these myths and tales.