If you’re a sushi lover, you owe a debt of gratitude to Kathleen Mary Drew-Baker.

Drew-Baker was a British phycologist, a practitioner of a branch of science so arcane that Google, questioned about it, insists that surely you meant “psychologist.” If you persist, however, you eventually discover that phycology is the study of algae, a diverse class of primitive plants, the largest of which are known as seaweeds.

Sushi depends on seaweed. Spicy tuna, abalone, eel, cucumber, yellowtail, and (in California rolls) avocado all come to the table encased in vinegary rice and wrapped in sheets of seaweed which—though distinctly green after processing—come from a species of red seaweed formally known as Porphyra. The Japanese call it nori.

The Japanese began