In Margaret Atwood's "Stone Mattress," the author explores the concept of stromatolites, fossilized structures created by the layering of blue-green algae. The term itself reflects this process, deriving from Greek words that suggest a stone-like cushion. Through this imagery, Atwood highlights their significance in Earth's history as these microorganisms played a critical role in producing the oxygen essential for life today.

The narrator's rhetorical questioning evokes wonder about the natural world and the astonishing connections between ancient life forms and modern existence. As we breathe the oxygen they produced millions of years ago, it invites readers to appreciate the profound impact of these simple yet vital organisms and their contributions to our planet's ecosystem.