Short answers, pulled from the story.
Lettuce was first domesticated near the Caucasus region, where seed shattering was the initial trait bred out of the wild ancestor. The earliest depictions of lettuce cultivation appear in ancient Egypt as far back as 2680 BC.
The word lettuce descends from the Roman Latin name lactuca, derived from lac meaning "milk", an allusion to the white latex that oozes from cut stems. The English word traveled through Middle English from the Old French letues or laitues.
Iceberg lettuce gets its name from the way it was transported in the early 20th century: the heads were packed in crushed ice, and they looked like icebergs rising above the frost. The variety was originally developed in 1894 by Burpee Seeds and Plants for growth in the northern United States.
At room temperature, lettuce seeds remain viable for only a few months. When newly harvested seed is stored cryogenically in vaporized nitrogen, the half-life extends to 500 years; stored in liquid nitrogen, that figure rises to 3,400 years.
World production of lettuce and chicory combined reached 28 million tonnes in 2023. China leads global production, accounting for 53 percent of the total.
Lettuce is almost always eaten raw rather than cooked, which means pathogens are not killed before consumption. Lettuce has been linked to outbreaks of E. coli O157:H7, Salmonella, Shigella, hepatitis A, and Giardia lamblia, among others.