The post-deluge story of Deucalion and his wife Pyrrha, described by Ovid in book 1 of his Metamorphoses, provides a clear example of spontaneous creation resulting from the proper comingling of the four basic elements. These elements—fire, air, water, and earth—were thought to fundamentally constitute the world at that time, a belief inherited from the ancient Greeks. Indeed, toward the very end of the poem, in book 15, Ovid's Pythagoras lays out a theory of creation-as-transformation in his wide-ranging monologues on these fundamental elements. His speech seems to bridge the world of myth and the scientific realm.
With regards to Deucalion and Pyrrha, the two are spared by Zeus when he unleashes a flood on all mankind, and they seek to repopulate the earth once they reach dry land by praying to Themis (see book 1, lines 348–380, and note that I refer to A. S. Kline’s translation throughout). The Titaness instructs Deucalion and Pyrrha to “throw behind [yourselves] the bones of your great mother!”—a command which leaves the couple dumbfounded. However, Deucalion comes to realize that Themis is referring to “mother” Earth, Gaia, and that they should throw stones, Gaia’s “bones,” over their shoulders instead. (This sequence is recounted in book 1, lines 381–415). Subsequently,
The stones ... began to lose their rigidity and hardness, and after a while softened, and once softened acquired new form. ... The earthy part, ... wet with moisture, turned to flesh; what was solid and inflexible mutated to bone ... (Book 1, lines 381–415)
Ovid, in his characteristically evocative language, is sure to note the “scientific” details and precise mechanisms of the miraculous transformation. The human flesh emanates from “the earthy part” of the stones—likely rocks’ outsides, which are typically embedded in the soil and therefore “wet with moisture.” Meanwhile, the hard interior of the stones (that part which was “solid and flexible”) fittingly becomes rigid bone.
Importantly, however, Ovid offers more than an anatomical comparison between the rocks and the human body; instead, he equates the creation that results from Deucalion and Pyrrha’s ritual to the special properties of the fundamental elements themselves. “In fact,” Ovid writes, “when heat and moisture are mixed they conceive, and from these two things the whole of life originates”—a process that begins with the transformation (literally, metamorphosis) of the stones and which eventually comes to include “the deep heaven-sent light of the sun [that] produced innumerable species, partly remaking previous forms, partly creating new monsters” (book 1, lines 416–437). Each element, whether earth or sun (i.e., fire), in addition to the water of the flood and the air beneath the sun, plays a crucial role in any new formation.
The “physics” of this fantastic creation event and many other transformations is corroborated in much greater detail by Pythagoras, whose lengthy monologue in book 15 serves as a bookend to the creation story in book 1. According to Ovid’s Pythagoras, “The everlasting universe contains four generative states of matter,” whose different densities, when combined in various ways, induce transformations that yield new creation. Hence, "fire condenses, turns into denser air, and this to water, and water, contracted, solidifies as earth,” Pythagoras says (book 15, lines 237–258).
Interestingly, Pythagoras’s theory of the elements comes to border on the scientific as he observes the natural processes of the world, in which limitless transformations do indeed occur even if we would not consider them to be wholly “mythic.” Pythagoras points to geological changes, such as those which are in fact represented in Deucalion and Pyrrha’s story. He says,
I have seen myself what was once firm land, become the sea: I have seen earth made from the waters: and seashells lie far away from the ocean, and an ancient anchor has been found on a mountaintop. (Book 15, lines 259–306)
Such ebbs and flows, which themselves take on the form of the fabulous as well as the scientific in the Metamorphoses, are paradigmatic of Ovid’s overall view of the world and the phenomenon of constant change.