Final answer:
The two prominent literary phenomena in the book of Genesis that underscore the book's theme of beginnings are Genealogy and Creation Stories.
Step-by-step explanation:
The two prominent literary phenomena in the book of Genesis that underscore the book's theme of beginnings are Genealogy and Creation Stories. Genealogy is evident in the detailed lineage of individuals, such as Adam and Eve and their descendants, while Creation Stories narrate the process of God creating the world and living creatures in it. These literary elements emphasize the origin and foundation of humanity and the universe as described in the book of Genesis.