Throughout the novel, Marie-Laure is associated with mollusks—she studies them and collects them as a child, and when she grows up, she becomes a noted scientist of mollusks. During her time in the French Resistance, Marie-Laure takes the code-name “the Whelk” for herself. The significance of the nickname is interesting: Marie-Laure admires whelks for their beauty, but also for their ability to withstand seagulls’ beaks and remain securely attached to rocks and stones. In essence, the whelk is then the perfect symbol for Marie-Laure’s desire for peace, constancy and stability in her life—the very things denied to her by the chaos of World War II. In a poignant, symbolic image that proves this point, Doerr shows the whelks and snails of the Saint-Malo grotto continuing to live safely and peacefully (even alongside the possibly-cursed Sea of Flames) while the human city all around them is destroyed.
Whelks, Mollusks, and Shells Quotes in All the Light We Cannot See
It is cut, polished; for a breath, it passes between the hands of men.
Another hour, another day, another year. Lump of carbon no larger than a chestnut. Mantled with algae, bedecked with barnacles. Crawled over by snails. It stirs among the pebbles.