The bite-sized oyster—raw, baked, or broiled on the half shell, bubbled with cream in oyster stew—is a delicious oyster. The foot-long oyster—the size of the shellfish that used to flourish in old New York Harbor’s pristine bay—is something else again. William Makepeace Thackeray, who gulped one of these down in 1852, remarked in horror that it was much like swallowing a baby.

Oysters, nowadays, aren’t everybody’s cup of tea—in fact, they routinely pop up on “Most Hated Foods” lists, along with Brussels sprouts, liver, and tofu—but our ancestors shamelessly adored them. Piles of post-feast oyster shells—known as middens—are found along coasts world-wide. One of the largest, in Denmark, dates to the Neolithic period and is roughly the size of the Titanic.

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