National Pig Day

The animal at the center of the day is one of the oldest partnerships between people and a large mammal. The domestic pig, Sus scrofa domesticus, descends from the wild boar, Sus scrofa, and the change from one to the other happened a very long time ago. Encyclopaedia Britannica dates the domestication of the pig to roughly 9,000 years ago, most likely in what is now Turkey.

It was not a single event in a single place. Pigs were tamed more than once. In China's Lower Yangtze region, archaeological evidence shows pig domestication was underway by about 8,000 years ago, developing alongside the first rice farms and settled villages. Two ancient human communities, on opposite sides of the continent, arrived at the same idea.

The holiday itself is much younger, and its origin is refreshingly small in scale. In 1972 two sisters decided the pig deserved a day. Ellen Stanley taught school in Lubbock, Texas; her sister, Mary Lynne Rave, lived in Beaufort, North Carolina. Together they registered March 1 as "Pig Day" in Chase's Calendar of Annual Events, the reference book that catalogs observances.

Stanley, the teacher, brought the new holiday into her own classroom, and the day spread mostly through schools, zoos, and word of mouth, with its strongest following in the American Midwest. There was no sponsor and no campaign. The sisters simply named a day, wrote down a reason, and let it travel.